JCB logo
amgmicro.com
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
This Article
Right arrow Full Text (PDF, 2859K)
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JCB
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Arnold, H. H.
Right arrow Articles by Salminen, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Arnold, H. H.
Right arrow Articles by Salminen, A.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Facebook   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

The Journal of Cell Biology, Vol 118, 877-887, Copyright © 1992 by The Rockefeller University Press

ARTICLES

Retinoic acid induces myogenin synthesis and myogenic differentiation in the rat rhabdomyosarcoma cell line BA-Han-1C

HH Arnold, CD Gerharz, HE Gabbert and A Salminen
Department of Toxicology, Medical School, University of Hamburg, Germany.

Two clonal rat rhabdomyosarcoma cell lines BA-Han-1B and BA-Han-1C with different capacities for myogenic differentiation have been examined for the expression of muscle regulatory basic helix-loop-helix (bHLH) proteins of the MyoD family. Whereas cells of the BA-Han-1C subpopulation constitutively expressed MyoD1 and could be induced to differentiate with retinoic acid (RA), BA-Han-1B cells did not express any of the myogenic control factors and appeared to be largely differentiation-defective. Upon induction with RA, BA-Han-1C cells expressed also myogenin, in contrast to BA-Han-1B cells which never activated any of the genes encoding muscle bHLH factors. The onset of myogenin transcription in BA-Han-1C cells required de novo protein synthesis and DNA replication suggesting that RA probably did not act directly on the myogenin gene. Although MyoD1 was expressed in proliferating BA-Han-1C myoblasts, muscle-specific reporter genes were not activated indicating that MyoD was biologically inactive. However, transfections with plasmid expressing additional MyoD1 protein resulted in the transactivation of muscle genes even in the absence of RA. mRNA encoding the negative regulatory HLH protein Id was expressed in proliferating BA-Han-1C cells and disappeared later after RA induction which suggested that it may be involved in the regulation of MyoD1 activity. The myogenic differentiation of malignant rhabdomyosarcoma cells strictly correlated with the activation of the myogenin gene. In fact, stable transfections of BA-Han-1C cells with myogenin expressing plasmids resulted in spontaneous differentiation. Together, our results suggest that the transformed and undifferentiated phenotype of BA-Han- 1C rhabdomyosarcoma cells is associated with the inactivation of the myogenic factor MyoD1 as well as lack of myogenin expression. RA alleviates the inhibition of myogenic differentiation, probably by activating MyoD protein and myogenin gene transcription. BA-Han-1B cells did not respond to RA and the differentiated phenotype could not be restored by overexpression of MyoD1 or myogenin.
Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Facebook Facebook   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents