title: The N-terminal of a heparin-binding sperm membrane mitogen possess lectin-like sequence.
abstract: Glycosaminoglycans like heparin and heparin sulfate in follicular fluid induce changes in the intracellular environment during the spermatozoal functional maturation. We previously reported the isolation, purification and partial characterization of a heparin binding sperm membrane protein (HBSM). In the present study, the amino acids analysis provided evidence of a single sequence, which suggest the homogeneity of the purified HBSM. Fourteen amino acids--(1)A D T I V A V E L D T Y P N(14)--correspond to the amino terminal sequence of Concanavalin A (Con A) and contain 45.2% carbohydrate by weight. HBSM possess mitogenic property on lymphocytes with comparable magnitude to the well-known mitogen; Con A, inducing 83% radiolabel thymidine incorporation in growing lymphocytes. Unlike Con A, there was no agglutination of cell by HBSM upto 5 ng/ml concentration. Interestingly, we found that heparin and chondroitin sulfate-conjugated HBSM inhibit the proliferative activity. Similar effect was also found with an in-house isolate sulfated glycans; G-I (28% sulfate). In contrast, there was no inhibition by the desulfated form; G-ID. Altogether, our data suggest that the mechanism of cell proliferative pathway may be different for HBSM and Con A.
authors.affiliation: Gamete Immunology Laboratory, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata, 700032 West Bengal, India.
authors.forename: Visesato
authors.initials: V
authors.lastname: Mor
authors.forename: Tapati
authors.initials: T
authors.lastname: Chatterjee
mesh_terms: D000371:Agglutination / Q000187:drug effects; D000595:Amino Acid Sequence; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004912:Erythrocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D006041:Goats; D006493:Heparin / Q000378:metabolism*; D008297:Male; D008934:Mitogens / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D008969:Molecular Sequence Data; D051381:Rats; D017207:Rats, Sprague-Dawley; D017386:Sequence Homology, Amino Acid; D012756:Sheep; D013094:Spermatozoa / Q000378:metabolism*
chemical_list: D008934:Mitogens; D006493:Heparin