ISSN:
1432-041X
Keywords:
Key words Cadherin
;
Amphibian
;
Lectin
;
GPI-anchor
;
ABO blood group
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Despite their wide distribution in various organisms, no physiological roles have been proposed for the human blood-group-ABO (ABH)-active trisaccharides. Here we show that monoclonal antibodies against human blood-group-B-active trisaccharides (B-substance) completely block the Ca2+-dependent cell-cell adhesion system of frog (Xenopus laevis) embryonic cells. Synthetic B-substance or B-active glycopeptides also disrupt the Ca2+ -dependent cell-cell adhesion. These results suggest that blood-group-B-active substances play a role in cell-cell adhesion. Blood-group-B-active substances were found as glycoproteins and as glycosphingolipids. In order to identify B-active glycoproteins active in cell-cell adhesion, we purified B-active membrane glycoproteins by two-dimensional electrophoresis and found that they are 45- to 58-kDa proteins with pI(s) ranging from 4.0 to 5.3. They are glycosylphosphatidyl inositol (GPI) anchored. Amino acid sequence analysis showed that the purified B-active GPI-anchored proteins are homologues of soluble Xenopus cortical granule lectins (CGL). The results suggest that the B-active membrane glycoproteins are GPI-anchored forms of the lectin and are directly involved in frog Ca 2+-dependent cell-cell adhesion.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004270050148
