Bovine adrenocortical cells exhibit high affinity transforming growth factor-beta receptors which are regulated by adrenocorticotropin.

摘要: Transforming growth factor beta (TGF-beta) at picomolar concentrations has been previously shown to induce striking alterations of bovine adrenocortical cell differentiated functions, without detectable effect on activity (Feige, J.J., Cochet, C., and Chambaz, E. M. (1986) Biochem. Biophys. Res. Commun. 139, 693-700; Hotta, M., Baird, A. Proc. Natl. Acad. Sci. U. S. 83, 7795-7799). Adrenocortical cells in culture could bind 125I-labeled TGF-beta through least two different binding systems. The highest affinity exhibited a Kd value 5.7 X 10(-10) M calculated capacity about 100,000 sites/cell, while the low system yielded values 4.3 10(-8) 2 10(6) respectively. bound be cross-linked using disuccinimidyl suberate subsequent electrophoretic analysis revealed that was associated with major components 280 kDa 70-75 kDa, respectively, latter one being resolved as labeled doublet. Thus exhibit receptor similar defined by Massague co-workers (Cheifetz, S., Like, B., Massague, J. Biol. Chem. 261,9972-9978) other types. Various factors, including fibroblast factor, well established hormonal activators such angiotensin II adrenocorticotropin, were examined their activity. A increase number high receptors selectively elicited ACTH nanomolar concentration range. This time- dose-dependent mimicked treatment dibutyryl cyclic AMP or forskolin. However, ACTH-induced not impaired when protein synthesis blocked. It is concluded are typical target for TGF-beta. endocrine represents model which, first time, level under regulation AMP-dependent pathway.