CTLDs in Caenorhabditis elegans

Sequence alignments: group 1 2 3 4 5 6 7 8 sugar-binding CTLDs
C. elegans proteins containing the CTLD motif have been compared to reveal their overall domain organization, to establish evolutionary relationships amongst the CTLDs and to determine the degree of conservation of amino acid residues that form Ca2+- and carbohydrate-binding sites in vertebrate C-type CRDs. The results raise the possibility that a small subset of these proteins have carbohydrate recognition functions analogous to those of vertebrate CRDs. 
A total of 183 CTLDs have been identified in 125 proteins encoded in the C. elegans genome. The CTLDs have been categorized into 8 evolutionary groups.  The CTLD-containing proteins have been classified based on the overall arrangement of structural modules within the polypeptides, and on sequence similarity between the CTLDs. They also have a characteristic set of disulfide bonding patterns.  The C. elegans proteins generally have different domain organization from known Drosophila melanogaster and mammalian proteins containing CTLDs.  Most of the CTLDs are divergent in sequence from those in mammalian proteins.  However, 19 show conservation of most of the amino acid residues that ligate Ca2+ to form a carbohydrate-binding site in vertebrate C-type CRDs.

Domain organization of CTLD-containing proteins in C elegans
CTLDs are coloured according to predicted sugar-binding specificity: blue, mannose; green, galactose; orange, N-acetylgalactosamine. 

Click on a protein architecture to view proteins in that family.
A1 proteins A2 proteins A3 proteins A4 proteins A5 proteins A6 proteins A7 proteins A8 proteins A9 proteins A10 proteins B1 proteins B2 proteins B3 proteins C1 proteins C2 proteins C3 proteins C4 proteins C5 proteins C6 proteins C7 proteins C8  proteins D1 proteins D2 proteins D3 proteins D4 proteins D5 proteins D6 proteins D7 proteins D8 proteins D9 proteins D10 proteins E proteins F1 proteins F2 proteins G1 proteins G2 proteins G3 proteins H proteins I proteins Domain organization of C. elegans CTLD-containing proteins

For further information see:

Drickamer, K and Dodd, RB (1999) C-type lectin-like domains in Caenorhabditis elegans: predictions from the complete genome sequence. Glycobiology, 9, 1357-1369.

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This page last updated:
Wednesday, 01 January 2014
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Contact information: This site is supported by:
Kurt Drickamer
Division of Molecular Biosciences
Faculty of Natural Sciences
Imperial College London
Email: k.drickamer@imperial.ac.uk