Ligand-binding activity and expression profile of annexins in Caenorhabditis elegans

J Biochem. 2007 Jan;141(1):47-55. doi: 10.1093/jb/mvm009. Epub 2006 Dec 14.

Abstract

Mammalian annexins are implicated in several physiological mechanisms based on their calcium-dependent phospholipid/membrane binding and carbohydrate-binding activities. In this study, we investigated gene expression profiles of all four Caenorhabditis elegans annexins, nex-1, -2, -3 and -4, throughout the development, and compared phospholipid- and carbohydrate-binding properties of their protein products, NEX-1, -2, -3 and -4. We found that nex-1 and -3 are transcribed continuously during the developmental stages, while expression of nex-2 and -4 appeared to be temporal, peaking at the L1 stage followed by a gradual decrease toward the adult stage. NEX-1 and -3 were detected as single protein band in total worm extracts by immunoblotting, but NEX-2 was heterogenic in size. NEX-1, -2, and -3 showed the binding activities to phosphatidylserine, phosphatidylinositol and phosphatidylethanolamine, but not to phosphatidylcholine. In contrast to their uniform phospholipids-binding properties, their glycosaminoglycan-binding activities were distinctive. NEX-2 bound to heparan sulfate and chondroitin, NEX-3 bound only to heparan sulfate, and NEX-1 showed no lectin activities under tested conditions. NEX-4 had neither phospholipids- nor carbohydrate-binding properties. Differentiated expression profiles and ligand-binding properties of NEX-1, -2, -3 and -4, shown in our study, may represent distinctive roles for each C. elegans annexins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Annexins / biosynthesis
  • Annexins / metabolism*
  • Caenorhabditis elegans / growth & development
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / biosynthesis
  • Caenorhabditis elegans Proteins / metabolism*
  • Chondroitin / metabolism
  • Gene Expression Profiling
  • Gene Expression Regulation, Developmental
  • Heparitin Sulfate / metabolism
  • Immunoblotting
  • Liposomes / metabolism
  • Molecular Sequence Data
  • Phospholipids / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Alignment

Substances

  • Annexins
  • Caenorhabditis elegans Proteins
  • Liposomes
  • Nex-1 protein, C elegans
  • Nex-2 protein, C elegans
  • Nex-3 protein, C elegans
  • Nex-4 protein, C elegans
  • Phospholipids
  • Chondroitin
  • Heparitin Sulfate