Characterization of naturally occurring myosin heavy chain antisense mRNA in rat heart.
Analysis of mRNA by Northern blot and reverse transcription-polymerase chain reaction demonstrated the expression of sense and considerable amounts of naturally occurring antisense mRNA for beta-myosin heavy chain (MHC) and alpha-MHC in the neonatal rat heart: antisense MHC mRNA expression of alpha-MHC and beta-MHC was approximately half of the corresponding sense MHC mRNA expression. Using a computational approach, we could identify a reverse Pol II promoter in the beta-MHC gene. Both sense and antisense MHC mRNA demonstrated similar sizes of approximately 6,000 bp in the Northern blot. Alpha-MHC antisense mRNA consisted of approximately 3,700 bp of complementary exon sequences and beta-MHC consisted of approximately 2,700 bp, suggesting a higher probability of alpha-MHC mRNA dimerization. Hence, sense mRNA transcripts and protein of alpha-MHC should exist at different relative levels in the neonatal state. In fact, the relative proportion of alpha-MHC was 52.0 +/- 2.6% on the sense mRNA but only 36.3 +/- 1.8% on the protein level. Because of its high abundance in the heart, we suggest that in the neonatal heart naturally occurring antisense mRNA may play a role in the regulation of MHC expression and, therefore, in the control of the energetical and contractile behaviour of the heart.
Luther
H P
HP
Medical Clinic I, Department of Cardiology, Humboldt-University (Charité), Berlin, Germany.
Haase
H
H
Hohaus
A
A
Beckmann
G
G
Reich
J
J
Morano
I
I
D000375:Aging / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D017931:DNA Primers; D008297:Male; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D018995:Myosin Heavy Chains / Q000235:genetics*; D011401:Promoter Regions, Genetic; D016372:RNA, Antisense / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D017931:DNA Primers; D016372:RNA, Antisense; D012333:RNA, Messenger; D018995:Myosin Heavy Chains