Inhibition of the cardiac alpha-actin gene in embryonic cardiac myocytes by dominant-negative serum response factor. Anat Rec A Discov Mol Cell Evol Biol 2003 Apr;271(2):315-21
Date
03/12/2003Pubmed ID
12629674DOI
10.1002/ar.a.10032Scopus ID
2-s2.0-0141994725 (requires institutional sign-in at Scopus site) 2 CitationsAbstract
Serum response factor (SRF), a transcription factor ubiquitously involved in the processes of cellular proliferation and differentiation, has been implicated in cardiac and skeletal muscle development because of its strong expression in embryonic muscle lineages, and its necessity for the transcription of transiently transfected muscle genes that contain SRF binding sites. This study was designed to ascertain whether SRF is required for the expression of an endogenous SRF-dependent gene during differentiation of early embryonic cardiac myocytes by introducing a dominant-negative SRF construct via retroviral delivery. Although no effect on overt cellular differentiation was detected, semi-quantitative RT-PCR revealed that expression of the SRF-dependent gene cardiac alpha-actin was inhibited, whereas expression of the non-SRF-dependent genes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and cardiac troponin-C was unaffected. No effect on myocyte proliferation was detected. Curiously, immunohistochemical localization of SRF protein suggested that whereas endogenous SRF was homogeneously dispersed throughout the cytoplasm and nucleus, the dominant-negative SRF protein was concentrated in the nucleus. These results extend previous findings using transiently transfected genes to the endogenous level, indicating that SRF is required for the full expression of muscle genes that contain SRF binding sites during cardiac myocyte differentiation.
Author List
Zhu X, McAllister D, Lough JAuthor
John W. Lough PhD Professor in the Cell Biology, Neurobiology and Anatomy department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
ActinsAnimals
Blotting, Northern
Blotting, Western
Cell Differentiation
Chick Embryo
DNA Primers
Gene Expression Regulation, Developmental
Genes, Dominant
Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+)
Immunoenzyme Techniques
Myocytes, Cardiac
Promoter Regions, Genetic
RNA, Messenger
Reverse Transcriptase Polymerase Chain Reaction
Serum Response Factor
Transcription, Genetic
Transfection
Troponin C