Stimulation of Membrane-Bound Guanylate Cyclase Activity by 17-β Estradiol

Abstract

Estrogen is known to exert both long-term genomic and short-term nongenomic actions. The long-term genomic actions of estrogen are mediated by the binding of estrogen to its cytoplasmic/nuclear receptor that subsequently triggers the transcription of target genes. In contrast, little is known about the molecular basis of the nongenomic actions of estrogen. We have found that 17-β estradiol activates membrane-bound guanylate cyclase and enhances atrial natriuretic factor (ANF)-stimulated guanylate cyclase activity in PC12 cell membranes. Membrane-bound guanylate cyclase, GC-A, contains an extracellular ANF-binding domain and an intracellular kinase-like domain plus catalytic domain. The kinase-like domain plus the catalytic domain of guanylate cyclase (GC-kc) can be expressed in E. Coli and functionally renatured. 17-β estradiol also activates the bacteria expressed GC-kc, indicating that 17-β estradiol can directly interact with membrane-bound guanylate cyclase. These results demonstrate that 17-β estradiol exerts a non-genomic action on membrane-bound guanylate cyclase.