Myosin-activating protein kinases are possible regulators of nonmuscle myosin in developing human heart.
We studied the localization of myosin-activating protein kinases in cardiomyocytes obtained from fetal human heart at 8-9 weeks gestation. It was found that at this developmental stage, smooth muscle/nonmuscle myosin light chain kinase (MLCK, 108 kDa) and its high-molecular weight isoform (MLCK, 210 kDa), skeletal MLCK and death-associated protein kinase (DAPK) are co-localized with nonmuscle myosin IIB in the premyofibrils. The data obtained suggest that cardiac nonmuscle myosin at 8-9 weeks gestation may serve as the substrate of the studied myosin-activating protein kinases that are likely to cooperatively regulate the formation of myofibrils. We revealed high-molecular weight isoform of smooth muscle/nonmuscle kinase MLCK-210 in developing human heart and determined the ratios of MLCK-108 and MLCK-210 at different gestational stages. In this case, the approximate time period of changes in these isoforms ratio was revealed (between 8-9 and 13 weeks), that can be associated with functional changes in the developing myocardium.
Institute of Clinical Cardiology, Russian Cardiology Research-and-Production Center, Ministry of Health Care and Social Development of the Russian Federation, Moscow, Russia. stepan@cardio.ru
O V
OV
Stepanova
A V
AV
Chadin
A G
AG
Masyutin
T G
TG
Kulikova
R A
RA
Poltavceva
V P
VP
Masenko
G T
GT
Sukhikh
D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002478:Cells, Cultured; D064550:Death-Associated Protein Kinases; D005260:Female; D006321:Heart / Q000196:embryology*; D006801:Humans; D032383:Myocytes, Cardiac / Q000378:metabolism*; D009210:Myofibrils / Q000378:metabolism; D009219:Myosin-Light-Chain Kinase / Q000378:metabolism*; D009218:Myosins / Q000378:metabolism*; D011247:Pregnancy; D012518:Sarcomeres / Q000378:metabolism
D051017:Apoptosis Regulatory Proteins; D064550:Death-Associated Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D009219:Myosin-Light-Chain Kinase; D009218:Myosins