ISSN:
1573-4919
Keywords:
cardiac
;
sarcoplasmic reticulum
;
calcium transport
;
protein kinase
;
phosphatase
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Summary Canine cardiac sarcoplasmic reticulum is phosphorylated by adenosine 3′,5′-monophosphate (cAMP)-dependent and by calcium · calmodulin-dependent protein kinases on a 27 000 proteolipid, called phospholamban. Both types of phosphorylation are associated with an increase in the initial rates of Ca2+ transport by SR vesicles which reflects an increased turnover of elementary steps of the calcium ATPase reaction sequence. The stimulatory effects of the protein kinases on the calcium pump may be reversed by an endogenous protein phosphatase, which can dephosphorylate both the CAMP-dependent and the calcium · calmodulin-dependent sites on phospholamban. Thus, the calcium pump in cardiac sarcoplasmic reticulum appears to be under reversible regulation mediated by protein kinases and protein phosphatases.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00242513
Permalink