Ligand-binding Activity and Expression Profile of Annexins in Caenorhabditis elegans

• Published in: Journal of biochemistry (Tokyo) 2007-01, Vol.141 (1), p.47-55
• Main Authors: Nishioka, Sara, Aikawa, Jun-ichi, Ida, Michiru, Matsumoto, Isamu, Street, Miyoko, Tsujimoto, Masafumi, Kojima-Aikawa, Kyoko
• Format: Article
• Language: English
• Subjects: 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
• ISSN: 0021-924X; 1756-2651
• DOI: 10.1093/jb/mvm009

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.