C-type lectin-like domain (CTLD) of the type found in lectins TC14, TC14-2, TC14-3, and TC14-4 from the budding tunicate Polyandrocarpa misakiensis and PfG6 from the Acorn worm
CLECT_TC14_like: C-type lectin-like domain (CTLD) of the type found in lectins TC14, TC14-2, TC14-3, and TC14-4 from the budding tunicate Polyandrocarpa misakiensis and PfG6 from the Acorn worm. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. TC14 is homodimeric. The CTLD of TC14 binds D-galactose and D-fucose. TC14 is expressed constitutively by multipotent epithelial and mesenchymal cells and plays in role during budding, in inducing the aggregation of undifferentiated mesenchymal cells to give rise to epithelial forming tissue. TC14-2 and TC14-3 shows calcium-dependent galactose binding activity. TC14-3 is a cytostatic factor which blocks cell growth and dedifferentiation of the atrial epithelium during asexual reproduction. It may also act as a differentiation inducing factor. Galactose inhibits the cytostatic activity of TC14-3. The gene for Acorn worm PfG6 is gill-specific; PfG6 may be a secreted protein.
Feature 1:carbohydrate binding site [chemical binding site]
Evidence:
Structure:1TLG_A, Polyandrocarpa misakiensis, TC14 bound with a calcium ion and D-galactose.
Comment:The 3 and 4-hydroxyl oxygen atoms of the carbohydrate co-ordinate with a bound calcium ion. Additional hydrogen bonds are formed between these hydroxyl groups and protein side chains involved in binding the Ca2+ ion.