Ca2+-binding protein, EF-hand superfamily [Signal transduction mechanisms];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166   9 LWNVFQRVDKDRSGVISDTELQqALSNGTWtpfnpvtvRSIISMFDRENKAGVNFSEFTGVWKYITDW------QNVFRT 82
Cdd:COG5126    7 LDRRFDLLDADGDGVLERDDFE-ALFRRLW--------ATLFSEADTDGDGRISREEFVAGMESLFEAtvepfaRAAFDL 77

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|...
gi 198443166  83 YDRDNSGMIDKNELKQALSGFGyrLSDQFHDILIRKFDRQGRGQIAFDDFIQG 135
Cdd:COG5126   78 LDTDGDGKISADEFRRLLTALG--VSEEEADELFARLDTDGDGKISFEEFVAA 128

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 198443166   73 ITDWQNVFRTYDRDNSGMIDKNELKQALSGFGYR--LSDQFHDILIRKFDRQGRGQIAFDDFIQ 134
Cdd:pfam13499   1 EEKLKEAFKLLDSDGDGYLDVEELKKLLRKLEEGepLSDEEVEELFKEFDLDKDGRISFEEFLE 64

Penta-EF hand, calcium binding motifs, found in Group I PEF proteins; The family corresponds to Group I PEF proteins that have been found not only in higher animals but also in lower animals, plants, fungi and protists. Group I PEF proteins include apoptosis-linked gene 2 protein (ALG-2), peflin and similar proteins. ALG-2, also termed programmed cell death protein 6 (PDCD6), is a widely expressed calcium-binding modulator protein associated with cell proliferation and death, as well as cell survival. It forms a homodimer in the cell or a heterodimer with its closest paralog peflin. Among the PEF proteins, ALG-2 can bind three Ca2+ ions through its EF1, EF3, and EF5 hands, where it is unique in that its EF5 hand binds Ca2+ ion in a canonical coordination. Peflin is a ubiquitously expressed 30-kD PEF protein containing five EF-hand motifs in its C-terminal domain and a longer N-terminal hydrophobic domain (NHB domain) than any other member of the PEF family. The NHB domain harbors nine repeats of a nonapeptide (A/PPGGPYGGP). Peflin may modulate the function of ALG-2 in Ca2+ signaling. It exists only as a heterodimer with ALG-2, and binds two Ca2+ ions through its EF1 and EF3 hands. Its additional EF5 hand is unpaired and does not bind Ca2+ ion but mediates the heterodimerization with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166   9 LWNVFQRVDKDRSGVISDTELQQALSNGTWTPFNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNS 88
Cdd:cd16180    2 LRRIFQAVDRDRSGRISAKELQRALSNGDWTPFSIETVRLMINMFDRDRSGTINFDEFVGLWKYIQDWRRLFRRFDRDRS 81

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  89 GMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGQIAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYLSMV 168
Cdd:cd16180   82 GSIDFNELQNALSSFGYRLSPQFVQLLVRKFDRRRRGSISFDDFVEACVTLKRLTDAFRKYDTNRTGYATISYEDFLTMV 161

                 ...
gi 198443166 169 FSI 171
Cdd:cd16180  162 LSI 164

EF-hand, calcium binding motif, found in peflin and similar proteins; Peflin, also termed penta-EF hand (PEF) protein with a long N-terminal hydrophobic domain, or penta-EF hand domain-containing protein 1, is a ubiquitously expressed 30-kD PEF protein containing five EF-hand motifs in its C-terminal domain and a longer N-terminal hydrophobic domain (NHB domain) than any other member of the PEF family. The NHB domain harbors nine repeats of a nonapeptide (A/PPGGPYGGP). Peflin may modulate the function of ALG-2 in Ca2+ signaling. It exists only as a heterodimer with ALG-2, and binds two Ca2+ ions through its EF1 and EF3 hands. Its additional EF5 hand is unpaired and does not bind Ca2+ ion but mediates the heterodimerization with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+. In lower vertebrates, peflin may interact with transient receptor potential N (TRPN1), suggesting a potential role of peflin in fast transducer channel adaptation.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166   9 LWNVFQRVDKDRSGVISDTELQQALSNGTWTPFNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNS 88
Cdd:cd16184    2 VQQWFQAVDRDRSGKISAKELQQALVNGNWSHFNDETCRLMIGMFDKDKSGTIDIYEFQALWNYIQQWKQVFQQFDRDRS 81

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  89 GMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGQIAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYLSMV 168
Cdd:cd16184   82 GSIDENELHQALSQMGYRLSPQFVQFLVSKYDPRARRSLTLDQFIQVCVQLQSLTDAFRQRDTQMTGTITISYEDFLTMA 161

                 ..
gi 198443166 169 FS 170
Cdd:cd16184  162 LL 163

EF-hand, calcium binding motif, found in homologs of mammalian apoptosis-linked gene 2 protein (ALG-2); The family includes some homologs of mammalian apoptosis-linked gene 2 protein (ALG-2) mainly found in lower eukaryotes, such as a parasitic protist Leishmarua major and a cellular slime mold Dictyostelium discoideum. These homologs contains five EF-hand motifs. Due to the presence of unfavorable residues at the Ca2+-coordinating positions, their non-canonical EF4 and EF5 hands may not bind Ca2+. Two Dictyostelium PEF proteins are the prototypes of this family. They may bind to cytoskeletal proteins and/or signal-transducing proteins localized to detergent-resistant membranes named lipid rafts, and occur as monomers or weak homo- or heterodimers like ALG-2. They can serve as a mediator for Ca2+ signaling-related Dictyostehum programmed cell death (PCD).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166   9 LWNVFQRVDKDRSGVISDTELQQALSNGTwTPFNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNS 88
Cdd:cd16185    2 LRQWFRAVDRDRSGSIDVNELQKALAGGG-LLFSLATAEKLIRMFDRDGNGTIDFEEFAALHQFLSNMQNGFEQRDTSRS 80

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 198443166  89 GMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGQIAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYL 165
Cdd:cd16185   81 GRLDANEVHEALAASGFQLDPPAFQALFRKFDPDRGGSLGFDDYIELCIFLASARNLFQAFDRQRTGRVTLDFNQFV 157

Penta-EF hand, calcium binding motifs, found in sorcin; Sorcin, also termed 22 kDa Ca2+-binding protein, CP-22, or V19, is a soluble resistance-related calcium-binding protein that is expressed in normal mammalian tissues, such as the liver, lungs and heart. The up-regulation of sorcin is correlated with a number of cancer types, including colorectal, gastric and breast cancer. It may represent a therapeutic target for reversing tumor multidrug resistance (MDR). Sorcin participates in the regulation of calcium homeostasis in cells and is necessary for the activation of mitosis and cytokinesis. It enhances metastasis and promotes epithelial-to-mesenchymal transition of colorectal cancer. Moreover, sorcin has been implicated in the regulation of intracellular Ca2+ cycling and cardiac excitation-contraction coupling. It displays the anti-apoptotic properties via the modulation of mitochondrial Ca2+ handling in cardiac myocytes. It can target and activate the sarcolemmal Na+/Ca2+ exchanger (NCX1) in cardiac muscle. Meanwhile, sorcin modulates cardiac L-type Ca2+ current by functional interaction with the alpha1C subunit. It also associates with calcium/calmodulin-dependent protein kinase IIdeltaC (CaMKIIdelta(C)) and further modulates ryanodine receptor (RyR) function in cardiac myocytes. Furthermore, sorcin may act as a Ca2+ sensor for glucose-induced nuclear translocation and the activation of carbohydrate-responsive element-binding protein (ChREBP)-dependent genes. As a mitochondrial chaperone TRAP1 interactor, sorcin involves in mitochondrial metabolism through the TRAP1 pathway. In addition, sorcin may regulate the inhibition of type I interferon response in cells through interacting with foot-and-mouth disease virus (FMDV) VP1. Sorcin contains a flexible glycine and proline-rich N-terminal extension and five EF-hand motifs that associate with membranes in a calcium-dependent manner. It may harbor three potential Ca2+ binding sites through its EF1, EF2 and EF3 hands. However, binding of only two Ca2+/monomer suffices to trigger the conformational change that exposes hydrophobic regions and leads to interaction with the respective targets. Sorcin forms homodimers through the association of the unpaired EF5 hand. Among the PEF proteins, sorcin is unique in that it contains potential phosphorylation sites by cAMP-dependent protein kinase (PKA), and it can form a tetramer at slightly acid pH values although remaining a stable dimer at neutral pH.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  22 GVISDTELQQALSN----GTWTPFNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNSGMIDKNELK 97
Cdd:cd16187   14 GQIDADELQRCLTQsgiaGGYKPFNLETCRLMISMLDRDMSGTMGFNEFKELWAVLNGWRQHFISFDSDRSGTVDPQELQ 93

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 198443166  98 QALSGFGYRLSDQFHDILIRKFDRQGRgqIAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYLSMVFSI 171
Cdd:cd16187   94 KALTTMGFRLSPQAVNSIAKRYSTNGK--ITFDDYIACCVKLRALTDSFRRRDTSQQGVVNFPYDDFIQCVMSI 165

Penta-EF hand, calcium binding motifs, found in Drosophila melanogaster calpain-A (CalpA), calpain-B (CalpB), and similar proteins; The family contains two calpains that have been found in Drosophila, CalpA and CalpB. CalpA, also termed calcium-activated neutral proteinase A (CANP A), or calpain-A catalytic subunit, is a Drosophila calpain homolog specifically expressed in a few neurons in the central nervous system, in scattered endocrine cells in the midgut, and in blood cells. CalpB, also termed calcium-activated neutral proteinase B (CANP B), contains calpain-B catalytic subunit 1 and calpain-B catalytic subunit 2. Both CalpA and CalpB are closely related to that of vertebrate calpains, and they share similar domain architecture, which consists of four domains: the N-terminal domain I, the catalytic domain II carrying the three active site residues, Cys, His and Asn, the Ca2+-regulated phospholipid-binding domain III, and penta-EF-hand Ca2+-binding domain IV. Besides, CalpA and CalpB display some distinguishing structural features that are not found in mammalian typical calpains. CalpA harbors a 76 amino acid long hydrophobic stretch inserted in domain IV, which may be involved in membrane attachment of this enzyme. CalpB has an unusually long N-terminal tail of 224 amino acids, which belongs to the class of intrinsically unstructured proteins (IUP) and may become ordered upon binding to target protein(s). Moreover, they do not need small regulatory subunits for their catalytic activity, and their proteolytic function is not regulated by an intrinsic inhibitor as the Drosophila genome contains neither regulatory subunit nor calpastatin orthologs. As a result, they may exist as a monomer or perhaps as a homo- or heterodimer together with a second large subunit. Furthermore, both CalpA and CalpB are dispensable for viability and fertility and do not share vital functions during Drosophila development. Phosphatidylinositol 4,5-diphosphate, phosphatidylinositol 4-monophosphate, phosphatidylinositol, and phosphatidic acid can stimulate the activity and the rate of activation of CalpA, but not CalpB. Calpain A modulates Toll responses by limited Cactus/IkappaB proteolysis. CalpB directly interacts with talin, an important component of the focal adhesion complex, and functions as an important modulator in border cell migration within egg chambers, which may act via the digestion of talin. CalpB can be phosphorylated by cAMP-dependent protein kinase (protein kinase A, PKA; EC 2.7.11.11) at Ser240 and Ser845, as well as by mitogen-activated protein kinase (ERK1 and ERK2; EC 2.7.11.24) at Thr747. The activation of the ERK pathway by extracellular signals results in the phosphorylation and activation of calpain B. In Schneider cells (S2), calpain B was mainly in the cytoplasm and upon a rise in Ca2+ the enzyme adhered to intracellular membranes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  20 RSGVISDTELQQALSNG-----TWTPFNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNSGMIDKN 94
Cdd:cd16196   12 EDMEIDAYELQDILNTAfkkdfPFDGFSLDACRSMVAMMDVDRSGKLGFEEFKKLWEDLRSWKRVFKLFDTDGSGSFSSF 91

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 198443166  95 ELKQALSGFGYRLSDQFHDILIRKFDRqGRGQIAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYLSMVF 169
Cdd:cd16196   92 ELRNALNSAGFRLSNATLNALVLRYSN-KDGRISFDDFIMCAVKLKTMFEIFKEKDPRGGGRATFNLDEFLESTM 165

Penta-EF hand, calcium binding motifs, found in calpain-12 (CAPN12); CAPN12, also termed calcium-activated neutral proteinase 12 (CANP 12), is a calpain large subunit mainly expressed in the cortex of the hair follicle. It may affect apoptosis regulation. CAPN12 contains a short N-terminal anchor helix, followed by a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  11 NVFQRVD-KDRSgvISDTELQQALS-----NGTWTP--FNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRT 82
Cdd:cd16194    4 QLFQELAgEDEE--INASELQKILSialerAHTSKPreFGLRTCRQLIQCFDHGQNGKLALEEFQQLWGYLLEWQAIFTK 81

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  83 YDRDNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFdRQGRGQIAFDDFIQgCivLQRLTDIFRR---YDTDQDGWIQV 159
Cdd:cd16194   82 FDEDTSGTMDSYELRLALNAAGFHLNNQLTETLTSRY-RDSRLRVDFESFLS-C--LAHLTCIFCQcsqHDDGGEGVICL 157

                 ....*....
gi 198443166 160 SYEQYLSMV 168
Cdd:cd16194  158 THRQWLELA 166

Penta-EF hand, calcium binding motifs, found in m-type calpain (CAPN2); CAPN2, also termed millimolar-calpain (m-calpain), or calpain-2 catalytic subunit, or calcium-activated neutral proteinase 2 (CANP 2), or calpain large polypeptide L2, or calpain-2 large subunit, is a ubiquitously expressed 80-kDa Ca2+-dependent intracellular cysteine protease that contains a short N-terminal anchor helix, followed by a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain. The catalytic subunit CAPN2 in complex with a regulatory subunit encoded by CAPNS1 forms an m-calpain heterodimer. CAPN2 acts as the key protease responsible for N-methyl-d-aspartic acid (NMDA)-induced cytoplasmic polyadenylation element-binding protein 3 (CPEB3) degradation in neurons. It cleaves several components of the focal adhesion complex, such as FAK and talin, triggering disassembly of the complex at the rear of the cell. The stimulation of CAPN2 activity is required for Golgi antiapoptotic proteins (GAAPs) to promote cleavage of FA kinase (FAK), cell spreading, and enhanced migration. calpain 2 is also involved in the onset of glial differentiation. It regulates proliferation, survival, migration, and tumorigenesis of breast cancer cells through a PP2A-Akt-FoxO-p27(Kip1) signaling cascade. Its expression is associated with response to platinum based chemotherapy, progression-free and overall survival in ovarian cancer. Moreover, CAPN2 may play a role in fundamental mitotic functions, such as the maintenance of sister chromatid cohesion. The activation of CAPN2 plays an essential role in hippocampal synaptic plasticity and in learning and memory. In the eye, CAPN2, together with a lens-specific variant of CAPN3, is responsible for proteolytic cleavages of alpha and beta-crystallin. Overactivated alpha and beta-crystallin can lead to cataract formation. Sometimes, CAPN2 compensates for loss of CAPN1, and both calpain isoforms are involved in AngII-induced aortic aneurysm formation. The main phosphorylation sites in m-calpain are Ser50 and Ser369/Thr370.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166   9 LWNVFQRVDKDRSGVISDTelqqalsngtwtpFNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNS 88
Cdd:cd16199   21 LQTILRRVLAKREDIKSDG-------------FSIETCKIMVDMLDSDGSGKLGLKEFYILWTKIQKYQKIYREIDVDRS 87

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 198443166  89 GMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRgQIAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYLSM 167
Cdd:cd16199   88 GTMNSYEMRKALEEAGFKLPCQLHQVIVARFADDDL-IIDFDNFVRCLVRLETLFKIFKQLDPENTGTIELDLISWLSF 165

Penta-EF hand, calcium binding motifs, found in calpain-13 (CAPN13), calpain-14 (CAPN14), and similar proteins; CAPN13, also termed calcium-activated neutral proteinase 13 (CANP 13), a 63.6 kDa calpain large subunit that exhibits a restricted tissue distribution with low levels of expression detected only in human testis and lung. In calpain family, CAPN13 is most closely related to calpain-14 (CAPN14). CAPN14, also termed calcium-activated neutral proteinase 14 (CANP 14), is a 76.7 kDa calpain large subunit that is most highly expressed in the oesophagus. Its expression and calpain activity can be induced by IL-13. Both CAPN13 and CAPN14 contain a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  19 DRSGVISDTELQQALSNGTWTPFNPVT-------VRSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNSGMI 91
Cdd:cd16195   11 DQGGELDAEQLQKLLNENLLKGLAGSGggfsldaCRSMVALMDLSVNGRLSLEEFSRLWKKLRKYKDIFQKADVSKSGFL 90

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 198443166  92 DKNELKQALSGFGYRLSDQ-FHDILIRKFDRQGRgqIAFDDFIQGCIVLQRLTDIFRRYDTDqDGWIQVSYEQYLSMV 168
Cdd:cd16195   91 SLSELRNAIQAAGIRVSDDlLNLMALRYGDSSGR--ISFESFICLMLRLECMAKIFRNLSKD-GGGIYLTESEWMQLT 165

Penta-EF hand, calcium binding motifs, found in calpain-8 (CAPN8); CAPN8, also termed new calpain 2 (nCL-2), or stomach-specific M-type calpain, is a calpain large subunit predominantly expressed in the stomach. It appears to be involved in membrane trafficking in the gastric surface mucus cells (pit cells), via its location at the Golgi and interaction with the beta-subunit of coatomer complex (beta-COP) of vesicles derived from the Golgi. Moreover, CAPN8, together with CAPN9, forms an active protease complex, G-calpain, in which both proteins are essential for stability and activity. The G-Calpain has been implicated in gastric mucosal defense. CAPN8 exists as both a monomer and homo-oligomer, but not as a heterodimer with the conventional calpain regulatory subunit (30K). The monomer and homodimer forms predominate. CAPN8 contains a short N-terminal anchor helix, followed by a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  11 NVFQRVDKDRSGViSDTELQQAL-----------SNGtwtpFNPVTVRSIISMFDRENKAGVNFSEFTGVWKYITDWQNV 79
Cdd:cd16191    4 NIFQKLAGKKCEV-TANELQTILnrvlskrkdikSDG----FTINTCREMISLLDTDGTGTLGLVEFRILWMKIQKYLAI 78

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  80 FRTYDRDNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGqIAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQV 159
Cdd:cd16191   79 YKKVDSDRSGTIDAHEMRNALQEAGFTLNNKIQQSIVQRYASNKLT-INFDGFIACMIRLETLFKMFQLLDKDKSGVVQL 157

                 ....*.
gi 198443166 160 SYEQYL 165
Cdd:cd16191  158 SLAEWL 163

Penta-EF hand, calcium binding motifs, found in Drosophila melanogaster calpain-C (CalpC) and similar proteins; CalpC, also termed calcium-activated neutral proteinase homolog C (CANP C), is a catalytically inactive homolog of CalpA and CalpB found in Drosophila. It is strongly expressed in the salivary glands. In contrast with CalpA and CalpB, both of which are closely related to that of vertebrate calpains, and they share similar domain architecture, which consists of four domains: the N-terminal domain I, the catalytic domain II carrying the three active site residues, Cys, His and Asn, the Ca2+-regulated phospholipid-binding domain III, and penta-EF-hand Ca2+-binding domain IV. CalpC is a truncated calpain form missing domain I and about 20 residues from domain II. Moreover, due to all three mutated active site residues (Cys to Arg, His to Val and Asn to Ser), it may not have proteolytic activity.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  47 RSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGrGQ 126
Cdd:cd16197   44 RQVVLLMDNSGLGRLKFQDFKDFMCSLKWWQGVFKMHTKEKTGILRAERLRDALEDVGFQLNTDVLSILILRYMRKD-GT 122

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....
gi 198443166 127 IAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYLSMVFS 170
Cdd:cd16197  123 LRFGDFVSAVLHLTAAFGSFEKKDPLQNGFIKLSLTEWLKSCLM 166

Penta-EF hand, calcium binding motifs, found in calpain-11 (CAPN11); CAPN11, also termed calcium-activated neutral proteinase 11 (CANP 11), is a mammalian orthologue of micro/m calpain. It is one of the calpain large subunits that appears to be exclusively expressed in certain cells of the testis. It may be involved in regulating calcium-dependent signal transduction events during meiosis and sperm functional processes. CAPN11 contains a short N-terminal anchor helix, followed by a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  47 RSIISMFDRENKAGVNFSEFTGVWKYITDWQNVFRTYDRDNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRgQ 126
Cdd:cd16193   46 RRMINLMDKDGSGKLGLHEFKILWKKIKKWMEIFKECDQDRSGNLNSYEMRLAIEKAGIKMNNRVTEVVVARYADDNM-I 124

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|.
gi 198443166 127 IAFDDFIQGCIVLQRLTDIFRRYDTDQDGWIQVSYEQYLSM 167
Cdd:cd16193  125 VDFDSFINCFLRLKAMFAFFLSMDTKKTGSICLSINQWLQI 165

calmodulin; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  13 FQRVDKDRSGVISDTELQQALSNGTWTPfNPVTVRSIISMFDRENKAGVNFSEF-TGVWKYITDWQN------VFRTYDR 85
Cdd:PTZ00184  17 FSLFDKDGDGTITTKELGTVMRSLGQNP-TEAELQDMINEVDADGNGTIDFPEFlTLMARKMKDTDSeeeikeAFKVFDR 95

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*....
gi 198443166  86 DNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGQIAFDDFIQ 134
Cdd:PTZ00184  96 DGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFVK 144

centrin; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  13 FQRVDKDRSGVISDTELQQALSNGTWTPFNPvTVRSIISMFDRENKAGVNFSEFTGVW-KYITDWQN------VFRTYDR 85
Cdd:PTZ00183  23 FDLFDTDGSGTIDPKELKVAMRSLGFEPKKE-EIKQMIADVDKDGSGKIDFEEFLDIMtKKLGERDPreeilkAFRLFDD 101

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*...
gi 198443166  86 DNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGQIAFDDFI 133
Cdd:PTZ00183 102 DKTGKISLKNLKRVAKELGETITDEELQEMIDEADRNGDGEISEEEFY 149

EF-hand, calcium binding motif, found in parvalbumin-like EF-hand family; The family includes alpha- and beta-parvalbumins, and a group of uncharacterized calglandulin-like proteins. Parvalbumins are small, acidic, cytosolic EF-hand-containing Ca2+-buffer and Ca2+ transporter/shuttle proteins belonging to EF-hand superfamily. They are expressed by vertebrates in fast-twitch muscle cells, specific neurons of the central and peripheral nervous system, sensory cells of the mammalian auditory organ (Corti's cell), and some other cells, and characterized by the presence of three consecutive EF-hand motifs (helix-loop-helix) called AB, CD, and EF, but only CD and EF can chelate metal ions, such as Ca2+ and Mg2+. Thus, they may play an additional role in Mg2+ handling. Moreover, parvalbumins represent one of the major animal allergens. In metal-bound states, parvalbumins possess a rigid and stable tertiary structure and display strong allergenicity. In contrast, the metal-free parvalbumins are intrinsically disordered, and the loss of metal ions results in a conformational change that decreases their IgE binding capacity. Furthermore, parvalbumins have been widely used as a neuronal marker for a variety of functional brain systems. They also function as a Ca2+ shuttle transporting Ca2+ from troponin-C (TnC) to the sarcoplasmic reticulum (SR) Ca2+ pump during muscle relaxation. Thus they may facilitate myocardial relaxation and play important roles in cardiac diastolic dysfunction. Parvalbumins consists of alpha- and beta- sublineages, which can be distinguished on the basis of isoelectric point (pI > 5 for alpha; pI

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 198443166  79 VFRTYDRDNSGMIDKNELKQALSGF---GYRLSDQFHDILIRKFDRQGRGQIAFDDF 132
Cdd:cd16251   39 VFQILDKDKSGFIEEEELKYILKGFsiaGRDLTDEETKALLAAGDTDGDGKIGVEEF 95

Ca2+-binding protein, EF-hand superfamily [Signal transduction mechanisms];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  73 ITDWQNVFRTYDRDNSGMIDKNELKQALSGFGYRLSDqfhdilirKFDRQGRGQIAFDDFIQG------CIVLQRLTDIF 146
Cdd:COG5126    4 RRKLDRRFDLLDADGDGVLERDDFEALFRRLWATLFS--------EADTDGDGRISREEFVAGmeslfeATVEPFARAAF 75

                         90
                 ....*....|.
gi 198443166 147 RRYDTDQDGWI 157
Cdd:COG5126   76 DLLDTDGDGKI 86

EF-hand, calcium binding motif, found in Drosophila melanogaster calbindin-32 (CBN) and similar proteins; CBN, the product of the cbn gene, is a Drosophila homolog to vertebrate neuronal six EF-hand calcium binding proteins. It is expressed through most of ontogenesis with a selective distribution in the nervous system and in a few small adult thoracic muscles. Its precise biological role remains unclear. CBN contains six EF-hand motifs, but some of them may not bind calcium ions due to the lack of key residues.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  17 DKDRSGVISDTELQQALSngtwtpfnpvTVRSIISMFDRENKagVNFS-EFTGVWkyitdwqnvfRTYDRDNSGMIDKNE 95
Cdd:cd16179   59 DENQDGRIDIRELAQLLP----------TEENFLLLFRRDNP--LDSSvEFMKVW----------REYDKDNSGYIEADE 116

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  96 LKQALS---GFGYRLSDQFHDILI-------RKFDRQGRGQIAFDDFIQ-----------------GCIVLQRLTDIFRR 148
Cdd:cd16179  117 LKNFLKhllKEAKRDNDVSEDKLIeytdtilQLFDRNKDGKLQLSEMARllpvkenflcrpifkgaGKLTREDIDRVFAL 196

                        170
                 ....*....|
gi 198443166 149 YDTDQDGWIQ 158
Cdd:cd16179  197 YDRDNNGTIE 206

EF-hand, calcium binding motif; A diverse superfamily of calcium sensors and calcium signal modulators; most examples in this alignment model have 2 active canonical EF hands. Ca2+ binding induces a conformational change in the EF-hand motif, leading to the activation or inactivation of target proteins. EF-hands tend to occur in pairs or higher copy numbers.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  12 VFQRVDKDRSGVISDTELQQALsngtwtpfnpvtvrsiismfdreNKAGVNFSEftgvwkyiTDWQNVFRTYDRDNSGMI 91
Cdd:cd00051    5 AFRLFDKDGDGTISADELKAAL-----------------------KSLGEGLSE--------EEIDEMIREVDKDGDGKI 53

                         90
                 ....*....|
gi 198443166  92 DKNELKQALS 101
Cdd:cd00051   54 DFEEFLELMA 63

EF-hand motif found in eukaryotic phosphoinositide-specific phospholipase C (PI-PLC, EC 3.1.4.11) isozymes; PI-PLC isozymes are signaling enzymes that hydrolyze the membrane phospholipids phosphatidylinositol-4,5-bisphosphate (PIP2) to generate two important second messengers in eukaryotic signal transduction cascades, Inositol 1,4,5-trisphosphate (InsP3) and diacylglycerol (DAG). InsP3 triggers inflow of calcium from intracellular stores, while DAG, together with calcium, activates protein kinase C, which goes on to phosphorylate other molecules, leading to altered cellular activity. Calcium is required for the catalysis. This family corresponds to the four EF-hand motifs containing PI-PLC isozymes, including PI-PLC-beta (1-4), -gamma (1-2), -delta (1,3,4), -epsilon (1), -zeta (1), eta (1-2). Lower eukaryotes such as yeast and slime molds contain only delta-type isozymes. In contrast, other types of isoforms present in higher eukaryotes. This family also includes 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase 1 (PLC1) from fungi. Some homologs from plants contain only two atypical EF-hand motifs and they are not included. All PI-PLC isozymes except sperm-specific PI-PLC-zeta share a core set of domains, including an N-terminal pleckstrin homology (PH) domain, four atypical EF-hand motifs, a PLC catalytic core, and a single C2 domain. PI-PLC-zeta lacks the PH domain. The PLC catalytic core domain is a TIM barrel with two highly conserved regions (X and Y) split by a highly degenerate linker sequence. Most of EF-hand motifs found in PI-PLCs consist of a helix-loop-helix structure, but lack residues critical to metal binding. Moreover, the EF-hand region of most of PI-PLCs may have an important regulatory function, but it has yet to be identified. However, PI-PLC-zeta is a key exception. It is responsible for Ca2+ oscillations in fertilized oocytes and exhibits a high sensitivity to Ca2+ mediated through its EF-hand domain. In addition, PI-PLC-eta2 shows a canonical EF-loop directing Ca2+-sensitivity and thus can amplify transient Ca2+ signals. Also it appears that PI-PLC-delta1 can regulate the binding of PH domain to PIP2 in a Ca2+-dependent manner through its functionally important EF-hand domains. PI-PLCs can be activated by a variety of extracellular ligands, such as growth factors, hormones, cytokines and lipids. Their activation has been implicated in tumorigenesis and/or metastasis linked to migration, proliferation, growth, inflammation, angiogenesis and actin cytoskeleton reorganization. PI-PLC-beta isozymes are activated by G-protein coupled receptor (GPCR) through different mechanisms. However, PI-PLC-gamma isozymes are activated by receptor tyrosine kinase (RTK), such as Rho and Ras GTPases. In contrast, PI-PLC-epsilon are activated by both GPCR and RTK. PI-PLC-delta1 and PLC-eta 1 are activated by GPCR-mediated calcium mobilization. The activation mechanism for PI-PLC-zeta remains unclear.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  77 QNVFRTYDRDNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGQIAFDDF---IQGCIVLQRLTDIFRRYDTDQ 153
Cdd:cd15898    3 RRQWIKADKDGDGKLSLKEIKKLLKRLNIRVSEKELKKLFKEVDTNGDGTLTFDEFeelYKSLTERPELEPIFKKYAGTN 82

                 ....*..
gi 198443166 154 DGWIQVS 160
Cdd:cd15898   83 RDYMTLE 89

EF-hand, calcium binding motif, found in parvalbumins; Parvalbumins are small, acidic, cytosolic EF-hand-containing Ca2+-buffer and Ca2+ transporter/shuttle proteins belonging to EF-hand superfamily. They are expressed by vertebrates in fast-twitch muscle cells, specific neurons of the central and peripheral nervous system, sensory cells of the mammalian auditory organ (Corti's cell), and some other cells, and characterized by the presence of three consecutive EF-hand motifs (helix-loop-helix) called AB, CD, and EF, but only CD and EF can chelate metal ions, such as Ca2+ and Mg2+. Thus, they may play an additional role in Mg2+ handling. Moreover, parvalbumins represent one of the major animal allergens. In metal-bound states, parvalbumins possess a rigid and stable tertiary structure and display strong allergenicity. In contrast, the metal-free parvalbumins are intrinsically disordered, and the loss of metal ions results in a conformational change that decreases their IgE binding capacity. Furthermore, parvalbumins have been widely used as a neuronal marker for a variety of functional brain systems. They also function as a Ca2+ shuttle transporting Ca2+ from troponin-C (TnC) to the sarcoplasmic reticulum (SR) Ca2+ pump during muscle relaxation. Thus they may facilitate myocardial relaxation and play important roles in cardiac diastolic dysfunction. Parvalbumins consists of alpha- and beta- sublineages, which can be distinguished on the basis of isoelectric point (pI > 5 for alpha; pI

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 198443166  75 DWQNVFRTYDRDNSGMIDKNELKQALSGF--GYR-LSDQFHDILIRKFDRQGRGQIAFDDF 132
Cdd:cd16253   35 DIKKVFNILDQDKSGFIEEEELKLFLKNFsdGARvLSDKETKNFLAAGDSDGDGKIGVDEF 95

EF-hand, calcium binding motif; EF-hands are calcium-binding motifs that occur at least in pairs. Links between disease states and genes encoding EF-hands, particularly the S100 subclass, are emerging. Each motif consists of a 12 residue loop flanked on either side by a 12 residue alpha-helix. EF-hands undergo a conformational change unpon binding calcium ions.

                           10        20
                   ....*....|....*....|....*..
gi 198443166    75 DWQNVFRTYDRDNSGMIDKNELKQALS 101
Cdd:smart00054   1 ELKEAFRLFDKDGDGKIDFEEFKDLLK 27

EF-hand, calcium binding motif, found in the hexa-EF hand proteins family; The hexa-EF hand proteins family, also named the calbindin sub-family, contains a group of six EF-hand Ca2+-binding proteins, including calretinin (CR, also termed 29 kDa calbindin), calbindin D28K (CB, also termed vitamin D-dependent calcium-binding protein, avian-type), and secretagogin (SCGN). CR is a cytosolic hexa-EF-hand calcium-binding protein predominantly expressed in a variety of normal and tumorigenic t-specific neurons of the central and peripheral nervous system. It is a multifunctional protein implicated in many biological processes, including cell proliferation, differentiation, and cell death. CB is highly expressed in brain tissue. It is a strong calcium-binding and buffering protein responsible for preventing a neuronal death as well as maintaining and controlling calcium homeostasis. SCGN is a six EF-hand calcium-binding protein expressed in neuroendocrine, pancreatic endocrine and retinal cells. It plays a crucial role in cell apoptosis, receptor signaling and differentiation. It is also involved in vesicle secretion through binding to various proteins, including interacts with SNAP25, SNAP23, DOC2alpha, ARFGAP2, rootletin, KIF5B, beta-tubulin, DDAH-2, ATP-synthase and myeloid leukemia factor 2. SCGN functions as a Ca2+ sensor/coincidence detector modulating vesicular exocytosis of neurotransmitters, neuropeptides or hormones. Although the family members share a significant amount of secondary sequence homology, they display altered structural and biochemical characteristics, and operate in distinct fashions. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions. CR contains six EF-hand motifs within two independent domains, CR I-II and CR III-VI. They harbor two and four EF-hand motifs, respectively. The first 5 EF-hand motifs are capable of binding calcium ions, while the EF-hand 6 is inactive. SCGN consists of the three globular domains each of which contains a pair of EF-hand motifs. Human SCGN simultaneously binds four calcium ions through its EF-hands 3, 4, 5 and 6 in one high affinity and three low affinity calcium-binding sites. In contrast, SCGNs in other lower eukaryotes, such as D. rerio, X. laevis, M. domestica, G. gallus, O. anatinus, are fully competent in terms of six calcium-binding.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  12 VFQRVDKDRSGVISDTELQQALSN---GTWTPFNPVTVR----SIISMFDRENKAGVNFSE--------------FTGVW 70
Cdd:cd15902   95 IWRKYDTDGSGFIEAKELKGFLKDlllKNKKHVSPPKLDeytkLILKEFDANKDGKLELDEmakllpvqenfllkFQILG 174

                         90       100       110
                 ....*....|....*....|....*....|
gi 198443166  71 KYIT---DWQNVFRTYDRDNSGMIDKNELK 97
Cdd:cd15902  175 AMDLtkeDFEKVFEHYDKDNNGVIEGNELD 204

EF-hand, calcium binding motif, found in the hexa-EF hand proteins family; The hexa-EF hand proteins family, also named the calbindin sub-family, contains a group of six EF-hand Ca2+-binding proteins, including calretinin (CR, also termed 29 kDa calbindin), calbindin D28K (CB, also termed vitamin D-dependent calcium-binding protein, avian-type), and secretagogin (SCGN). CR is a cytosolic hexa-EF-hand calcium-binding protein predominantly expressed in a variety of normal and tumorigenic t-specific neurons of the central and peripheral nervous system. It is a multifunctional protein implicated in many biological processes, including cell proliferation, differentiation, and cell death. CB is highly expressed in brain tissue. It is a strong calcium-binding and buffering protein responsible for preventing a neuronal death as well as maintaining and controlling calcium homeostasis. SCGN is a six EF-hand calcium-binding protein expressed in neuroendocrine, pancreatic endocrine and retinal cells. It plays a crucial role in cell apoptosis, receptor signaling and differentiation. It is also involved in vesicle secretion through binding to various proteins, including interacts with SNAP25, SNAP23, DOC2alpha, ARFGAP2, rootletin, KIF5B, beta-tubulin, DDAH-2, ATP-synthase and myeloid leukemia factor 2. SCGN functions as a Ca2+ sensor/coincidence detector modulating vesicular exocytosis of neurotransmitters, neuropeptides or hormones. Although the family members share a significant amount of secondary sequence homology, they display altered structural and biochemical characteristics, and operate in distinct fashions. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions. CR contains six EF-hand motifs within two independent domains, CR I-II and CR III-VI. They harbor two and four EF-hand motifs, respectively. The first 5 EF-hand motifs are capable of binding calcium ions, while the EF-hand 6 is inactive. SCGN consists of the three globular domains each of which contains a pair of EF-hand motifs. Human SCGN simultaneously binds four calcium ions through its EF-hands 3, 4, 5 and 6 in one high affinity and three low affinity calcium-binding sites. In contrast, SCGNs in other lower eukaryotes, such as D. rerio, X. laevis, M. domestica, G. gallus, O. anatinus, are fully competent in terms of six calcium-binding.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  14 QRVDKDRSGVISDTELQQALsngtwtpfnpVTVRSIISMFDRENKagvnfsEFTGVwkyitDWQNVFRTYDRDNSGMIDK 93
Cdd:cd15902   51 EKYDENEDGKIEIRELANIL----------PTEENFLLLFRREQP------LISSV-----EFMKIWRKYDTDGSGFIEA 109

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  94 NEL----KQALSGFGYRLSDQ----FHDILIRKFDRQGRGQIAFDDF---------------IQGCIVLQR--LTDIFRR 148
Cdd:cd15902  110 KELkgflKDLLLKNKKHVSPPkldeYTKLILKEFDANKDGKLELDEMakllpvqenfllkfqILGAMDLTKedFEKVFEH 189

                        170
                 ....*....|.
gi 198443166 149 YDTDQDGWIQV 159
Cdd:cd15902  190 YDKDNNGVIEG 200

calmodulin; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 198443166  73 ITDWQNVFRTYDRDNSGMIDKNELKQALSGFGYRLSDQFHDILIRKFDRQGRGQIAFDDFI-------QGCIVLQRLTDI 145
Cdd:PTZ00184  10 IAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLtlmarkmKDTDSEEEIKEA 89

                         90
                 ....*....|..
gi 198443166 146 FRRYDTDQDGWI 157
Cdd:PTZ00184  90 FKVFDRDGNGFI 101