A. Froeschle et al., RETINOIC ACID RECEPTORS AND MUSCLE B-HLH PROTEINS - PARTNERS IN RETINOID-INDUCED MYOGENESIS, Oncogene, 16(26), 1998, pp. 3369-3378
The results reported here indicate that retinoic acid (RA) induces gro
wth arrest and differentiation only in MyoD-expressing muscle cells. T
ransient transfection assays reveal a functional interaction between M
yoD, a key myogenic regulator and RA-receptors, principal mediators of
RA actions, Interestingly, we demonstrate that RXR-MyoD-containing co
mplexes are recruited at specific MyoD DNA-binding sites in muscle cel
ls, Furthermore, we also demonstrate that RA-receptors and the muscle
basic helix-loop-helix (b-HLH) proteins interact physically. Mutationa
l analysis suggests that this interaction occurs via the basic region
of muscle b-HLH proteins and the DIVA-binding domain of RA-receptors a
nd is important for functional interactions between these two families
of transcription factors. In conclusion, these results highlight nove
l interactions between two distinct groups of regulatory proteins that
influence cell growth and differentiation.