U-box domain, a modified RING finger, found in pre-mRNA-processing factor 19 (Prp19) and similar proteins; Prp19, also known as nuclear matrix protein 200 (NMP200), senescence evasion factor (SNEV), or DNA repair protein Pso4 (psoralen-sensitive mutant 4), is a ubiquitously expressed multifunctional E3 ubiquitin ligase with pleiotropic activities in DNA damage signaling, repair, and replicative senescence. It functions as a critical component of DNA repair and DNA damage checkpoint complexes. It senses DNA damage, binds double-stranded DNA in a sequence-independent manner, facilitates processing of damaged DNA, promotes DNA end joining, regulates replication protein A (RPA2) phosphorylation and ubiquitination at damaged DNA, and regulates RNA splicing and mitotic spindle formation in its integral capacity as a scaffold for a multimeric core complex. Prp19 contains an N-terminal E3 ubiquitin ligase U-box domain with E2 recruitment function that facilitates dimerization and is essential for its auto-ubiquitination activity in vitro or when overexpressed, a coiled-coil Prp19 homology region that mediates its tetramerization and interaction with CDC5L and SPF27, and a C-terminal seven-bladed WD40 beta-propeller type of leucine-rich architectural repeats that form an asymmetrical barrel-shaped structure important for substrate recognition and recruitment.

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gi 238941232   1 MFCAISGKPPRTPVVSLVSKCVFEKDLIEQYIQETGNDPISNAPLSVDQLLII 53
Cdd:cd16656    1 MVCAISGEVPEEPVVSPKSGHVFEKRLIEKYIAENGTDPVTGEPLTEEDLIEI 53

U-box domain, a modified RING finger, found in pre-mRNA-processing factor 19 (Prp19) and similar proteins; Prp19, also known as nuclear matrix protein 200 (NMP200), senescence evasion factor (SNEV), or DNA repair protein Pso4 (psoralen-sensitive mutant 4), is a ubiquitously expressed multifunctional E3 ubiquitin ligase with pleiotropic activities in DNA damage signaling, repair, and replicative senescence. It functions as a critical component of DNA repair and DNA damage checkpoint complexes. It senses DNA damage, binds double-stranded DNA in a sequence-independent manner, facilitates processing of damaged DNA, promotes DNA end joining, regulates replication protein A (RPA2) phosphorylation and ubiquitination at damaged DNA, and regulates RNA splicing and mitotic spindle formation in its integral capacity as a scaffold for a multimeric core complex. Prp19 contains an N-terminal E3 ubiquitin ligase U-box domain with E2 recruitment function that facilitates dimerization and is essential for its auto-ubiquitination activity in vitro or when overexpressed, a coiled-coil Prp19 homology region that mediates its tetramerization and interaction with CDC5L and SPF27, and a C-terminal seven-bladed WD40 beta-propeller type of leucine-rich architectural repeats that form an asymmetrical barrel-shaped structure important for substrate recognition and recruitment.

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                 ....*....|....*....|....*....|....*....|....*....|...
gi 238941232   1 MFCAISGKPPRTPVVSLVSKCVFEKDLIEQYIQETGNDPISNAPLSVDQLLII 53
Cdd:cd16656    1 MVCAISGEVPEEPVVSPKSGHVFEKRLIEKYIAENGTDPVTGEPLTEEDLIEI 53

U-box domain, a modified RING finger, found in pre-mRNA-processing factor 19 (Prp19) and similar proteins; Prp19, also known as nuclear matrix protein 200 (NMP200), senescence evasion factor (SNEV), or DNA repair protein Pso4 (psoralen-sensitive mutant 4), is a ubiquitously expressed multifunctional E3 ubiquitin ligase with pleiotropic activities in DNA damage signaling, repair, and replicative senescence. It functions as a critical component of DNA repair and DNA damage checkpoint complexes. It senses DNA damage, binds double-stranded DNA in a sequence-independent manner, facilitates processing of damaged DNA, promotes DNA end joining, regulates replication protein A (RPA2) phosphorylation and ubiquitination at damaged DNA, and regulates RNA splicing and mitotic spindle formation in its integral capacity as a scaffold for a multimeric core complex. Prp19 contains an N-terminal E3 ubiquitin ligase U-box domain with E2 recruitment function that facilitates dimerization and is essential for its auto-ubiquitination activity in vitro or when overexpressed, a coiled-coil Prp19 homology region that mediates its tetramerization and interaction with CDC5L and SPF27, and a C-terminal seven-bladed WD40 beta-propeller type of leucine-rich architectural repeats that form an asymmetrical barrel-shaped structure important for substrate recognition and recruitment.

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                 ....*....|....*....|....*....|....*....|....*....|...
gi 238941232   1 MFCAISGKPPRTPVVSLVSKCVFEKDLIEQYIQETGNDPISNAPLSVDQLLII 53
Cdd:cd16656    1 MVCAISGEVPEEPVVSPKSGHVFEKRLIEKYIAENGTDPVTGEPLTEEDLIEI 53

U-box domain, a modified RING finger; The U-box protein family is a family of E3 enzymes that also includes the HECT family and the RING finger family. The E3 enzyme is ubiquitin-protein ligase that cooperates with a ubiquitin-activating enzyme (E1) and a ubiquitin-conjugating enzyme (E2), and plays a central role in determining the specificity of the ubiquitination system. It removes the ubiquitin molecule from the E2 enzyme and attaches it to the target substrate, forming a covalent bond between ubiquitin and the target. U-box proteins are characterized by the presence of a U-box domain of approximately 70 amino acids. The U-box is a modified form of the RING finger domain that lacks metal chelating cysteines and histidines. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms.

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gi 238941232   3 CAISGKPPRTPVVSLvSKCVFEKDLIEQYIQETGNDPISNAPL 45
Cdd:cd16453    3 CPISGELMKDPVITP-SGITYDRSAIERWLLSDNTDPFTREPL 44

SPL-RING finger found in E3 SUMO-protein ligase NSE2 and similar proteins; NSE2, also known as MMS21 homolog (MMS21) or non-structural maintenance of chromosomes element 2 homolog (Non-SMC element 2 homolog, NSMCE2), is an autosumoylating small ubiquitin-like modifier (SUMO) ligase required for the response to DNA damage. It regulates sumoylation and nuclear-to-cytoplasmic translocation of skeletal and heart muscle-specific variant of the alpha subunit of nascent polypeptide associated complex (skNAC)-Smyd1 in myogenesis. It is also required for resisting extrinsically induced genotoxic stress. Moreover, NSE2 together with its partner proteins SMC6 and SMC5 form a tight subcomplex of the structural maintenance of chromosomes SMC5-6 complex, which includes another two subcomplexes, NSE1-NSE3-NSE4 and NSE5-NSE6. SMC6 and NSE3 are sumoylated in an NSE2-dependent manner, but SMC5 and NSE1 are not. NSE2-dependent E3 SUMO ligase activity is required for efficient DNA repair, but not for SMC5-6 complex stability. NSE2 contains a RING variant known as a Siz/PIAS (protein inhibitor of activated signal transducer and activator of transcription)-like RING (SPL-RING) finger that is likely shared by the SP-RING type SUMO E3 ligases, such as PIAS family proteins. The SPL-RING finger is a variant of the RING finger, which lacks the second, fifth, and sixth zinc-binding residues of the consensus C3H2C3-/C3HC4-type RING fingers. It harbors only one Zn binding site and is required for the sumoylating activity.

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gi 238941232   1 MFCAISGKPPRTPVVSLVSKCVFEKDLIEQYIQETGN 37
Cdd:cd16651    1 LKCPITQQLMVDPVRNKKCGHTYEKAAILQYLQSRKK 37