Regulation of naturally occurring antisense RNA of myosin heavy chain (MyHC) in neonatal cardiomyocytes

✍ Scribed by H.P. Luther; H. Bartsch; I. Morano; S. Podlowski; G. Baumann

• Book ID: 102300376
• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 174 KB
• Volume: 94
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/jcb.20319

✦ Synopsis

Abstract

Naturally occurring antisense RNA has been detected for a range of eukaryotic genes. Its abundance compared to levels of its complementary sense mRNA appears to be a factor indicating its possible regulatory function. In previous studies, we detected appreciable levels of antisense RNA against the two isoforms (α and β) of the heavy myosin‐chain (MyHC) in the myocardium of rats. If this is to play a significant role in gene expression antisense levels should vary in response to external and internal cellular influences. Recently, a bidirectional promoter located in the α/β MyHC intergenic region was described, which was proposed to regulate coordinated transcription of α‐MyHC sense and β‐MyHC antisense. To study MyHC antisense regulation in neonatal heart, we investigated cultivated myocytes stimulated with either trijodthyronin (T3) as an inductor of α‐MyHC or phenylephrine with stimulation of β‐MyHC. RNA‐quantification of sense and antisense transcripts of both isoforms was performed by real‐time RT‐PCR. Stimulation by T3 led to an induction of both sense and antisense of α‐MyHC and to a decrease of β‐MyHC sense and antisense. Phenylephrine increased sense and antisense β‐MyHC but reduced antisense α‐MyHC. The sense/antisense of α‐ and β‐MyHC ratio was unchanged compared to control. Results indicate a coregulation of sense and antisense MyHC RNA under stimulation of T3 and phenylephrine in neonatal cardiomyocytes. © 2004 Wiley‐Liss, Inc.