Isolation and characterization of native activin B.

摘要: To examine whether activin binds to follistatin, an activin-binding protein, form a complex in vivo, we attempted purify activin-follistatin from porcine follicular fluid. Our results thus obtained indicated that almost equimolar amounts of activins A, AB, and B are present as with follistatin the Reverse-phase high performance liquid chromatography purified yielded B. The activity was found be significantly lower than those other various assay systems such stimulation follicle-stimulating hormone secretion, induction erythrodifferentiation, potentiation expression gonadotropin receptors on ovarian cells. Moreover, binding 125I-activin A erythroleukemic cells which activin-responsive competed by approximately 10-fold potency compared activins. In contrast these results, proved have potent Xenopus mesoderm-inducing activity, comparable This indicates that, unlike can only elicit cannot function biological systems, suggesting specific role early development unknown functions.