Bicarbonate-regulated soluble adenylyl cyclase. Review uri icon

Overview

abstract

  • Soluble adenylyl cyclase (sAC) represents a novel form of mammalian adenylyl cyclase structurally, molecularly, and biochemically distinct from the G protein-regulated, transmembrane adenylyl cyclases (tmACs). sAC possesses no transmembrane domains and is insensitive to classic modulators of tmACs, such as heterotrimeric G proteins and P site ligands. Thus, sAC defines an independently regulated cAMP signaling system within mammalian cells. sAC is directly stimulated by bicarbonate ion both in vivo in heterologously expressing cells and in vitro using purified protein. sAC appears to be the predominant form of adenylyl cyclase (AC) in mammalian sperm, and its direct activation by bicarbonate provides a mechanism for generating the cAMP required to complete the bicarbonate-induced processes necessary for fertilization, including hyperactivated motility, capacitation, and the acrosome reaction. Immunolocalization studies reveal sAC is also abundantly expressed in other tissues which respond to bicarbonate or carbon dioxide levels suggesting it may function as a general bicarbonate/CO(2) sensor throughout the body.

publication date

  • July 1, 2001

Research

keywords

  • Adenylyl Cyclases
  • Bicarbonates

Identity

Scopus Document Identifier

  • 0035411545

PubMed ID

  • 11875252

Additional Document Info

volume

  • 2

issue

  • 4 Suppl