Open AccessPattern Formation on Cardiac Troponin I by Consecutive Phosphorylation and Dephosphorylation
Author(s) -
Jaquet Kornelia,
Thieleczek Rolf,
Heilmeyer Ludwig M. G.
Publication year - 1995
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1995.0486e.x
Subject(s) - dephosphorylation , phosphorylation , phosphatase , protein kinase a , protein phosphatase 2 , biochemistry , protein phosphorylation , serine , chemistry , kinase , troponin i , troponin , medicine , myocardial infarction
Two serine residues located adjacently in the heart‐specific N‐terminus of cardiac troponin I can be phosphorylated in vivo. Both residues are sequentially phosphorylated and dephosphorylated by cAMP‐dependent protein kinase (PKA) and protein phosphatase 2A (PP2A). The concentration changes of the different troponin I species have been determined separately for the phosphorylation and dephosphorylation reaction and approximated by time courses predicted by a reaction model. Dependent on the concentration ratio of active protein kinase/protein phosphatase, four different troponin I species can be generated; one nonphosphorylated, two monophosphorylated and one bisphosphorylated. This pattern generation will be observed in proteins phosphorylated and dephosphorylated by a single protein kinase and phosphatase on more than one site and is a new principle inherent in signal cascades.