Open AccessCalmodulin‐dependent protein phosphorylation and calcium uptake in rat‐liver microsomes
Author(s) -
FAMULSKI Konrad Stanislaw,
CARAFOLI Ernesto
Publication year - 1984
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1984.tb08149.x
Subject(s) - calmodulin , microsome , phosphorylation , calcium , protein phosphorylation , chemistry , biochemistry , calcium binding protein , in vitro , protein kinase a , organic chemistry
A 20‐kDa protein becomes phosphorylated in a process stimulated by Ca 2+ and calmodulin in the light microsomal fraction of rat liver homogenate. The uptake of Ca 2+ in light microsomal fraction is also calmodulin‐stimulated. The stimulation of Ca 2+ transport is associated with the operation of a protein phosphorylation system dependent on Ca 2+ and calmodulin. Transport is inhibited by a protein phosphatase which is stimulated by Ca 2+ and calmodulin. It is proposed that the phosphorylation of the 20‐kDa protein, which is stimulated by Ca 2+ and calmodulin, plays a role in the regulation of the microsomal Ca 2+ , Mg 2+ ‐ATPase.