del Pino E J, Cabada M O
Departamento de Biología del Desarrollo, Universidad Nacional de Tucumán, San Miguel de Tucumán, Argentina.
Gamete Res. 1987 Aug;17(4):333-42. doi: 10.1002/mrd.1120170406.
Incubation of dejellied spawned oocytes from Bufo arenarum with different lectins results in a decrease of oocyte fertility. Concanavalin A was the most effective lectin; phytohemagglutinin P and wheat germ lectin were less effective. Agglutinin from soybean was scarcely active. These lectin effects could be ascribed to a hindering of specific sites for some proteases, since the same treatment renders the oocyte vitelline envelope insensitive to spermatolysin (an essential requisite for fertilization) and to trypsin. Also in this case concanavalin A was the most effective lectin. Univalent concanavalin A was also effective in blocking the fertility of dejellied oocytes. These results indicate that the residues of alpha-D-glucose and alpha-D-mannose present in the vitelline envelope are involved in gamete interactions in Bufo arenarum. This idea is also supported by the finding that dejellied oocytes (fertilizables) have a number of binding sites for concanavalin A that is three or four orders of magnitude higher than coelomic or fertilized oocytes (both not penetrable by spermatozoa).
用不同凝集素孵育去除胶膜的南美蟾蜍产出的卵母细胞会导致卵母细胞受精能力下降。伴刀豆球蛋白A是最有效的凝集素；植物血凝素P和麦胚凝集素的效果较差。大豆凝集素几乎没有活性。这些凝集素的作用可能归因于对某些蛋白酶特定位点的阻碍，因为相同处理会使卵母细胞的卵黄膜对精子溶素（受精的必要条件）和胰蛋白酶不敏感。同样在这种情况下，伴刀豆球蛋白A是最有效的凝集素。单价伴刀豆球蛋白A在阻断去除胶膜的卵母细胞的受精能力方面也有效。这些结果表明，卵黄膜中存在的α-D-葡萄糖和α-D-甘露糖残基参与了南美蟾蜍的配子相互作用。去除胶膜的卵母细胞（可受精）对伴刀豆球蛋白A的结合位点数量比体腔或受精的卵母细胞（两者精子均无法穿透）高三个或四个数量级，这一发现也支持了这一观点。
