Differential synthesis by cultured atrial and ventricular rat cardiac myocytes of myosin light chain isoforms.
Dissociated cells from neonatal rat atria and ventricles were cultured in monolayers for 3 days. Newly synthesized 35S-methionine labeled myosin light chain isoforms ALC-1, ALC-2 (atrial) and VLC-1, VLC-2 (ventricular) were identified on 2D gels, and their pattern of synthesis was compared to that of myocard fragments immediately after explanation. ALCs were synthesized in 5- to 10-fold excess over VLCs by atrial cultures, whereas the converse was true for ventricular cultures, with two exceptions: one third of the LC-1 synthesized by ventricular fragments was ALC-1, and dissociated atrial cells synthesized very little LC-2 of either isoform. The former finding corresponds to the relatively high proportion of ALC-1 in neonatal ventricular tissue. We conclude that the regional programme of LC isoform expression is basically retained after tissue explantation and even after dissociation and culturing of cardiac myocytes.
Brand
T
T
MPI für Physiologische und Klinische Forschung, Abteilung Experimentelle Kardiologie, Bad Nauheim, Germany.
Milting
H
H
Zippel
M
M
Jockusch
H
H
D000818:Animals; D000831:Animals, Newborn; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D015180:Electrophoresis, Gel, Two-Dimensional; D006325:Heart Atria / Q000378:metabolism; D006352:Heart Ventricles / Q000378:metabolism; D008715:Methionine / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D009218:Myosins / Q000096:biosynthesis* / Q000302:isolation & purification; D051381:Rats; D011919:Rats, Inbred Strains
D000911:Antibodies, Monoclonal; D008715:Methionine; D009218:Myosins