Tissue-specific transcriptional control of alpha- and beta-tropomyosins in chicken muscle development.
During muscle maturation, isoform switching of contractile proteins to attain the adult phenotype involves both stage-specific and muscle-specific regulatory mechanisms. Chicken pectoralis major (PM) provides an interesting model to study the latter since a specific pattern of tropomyosin (TM) with repression of the beta TM isoform is displayed by the adult PM. The developmental pattern of alpha and beta fast skeletal muscle tropomyosins' (alpha f and beta TM) RNAs was investigated with 3' untranslated region specific probes. In PM, the beta TM messenger ceased to accumulate after hatching through a transcriptional control, as shown by run-on assays, so that, at Day 8 ex ovo, no beta TM mRNA was detected. In this same muscle, in parallel with the disappearance of the beta TM mRNA, there was a boost in the accumulation of the alpha f TM mRNA. In the leg muscles, following hatching, there was only a moderate increase in the level of the alpha f TM mRNA, together with a slight decrease in the accumulation of the beta TM mRNA. Taken together, these results show that chicken muscle maturation involves tissue-specific transcriptional control of tropomyosin genes and could suggest a possible coordinate regulation of the two genes.
Meinnel
T
T
Department of Molecular Biology, Pasteur Institute, Paris, France.
Libri
D
D
Mouly
V
V
Gros
D
D
Fiszman
M Y
MY
Lemonnier
M
M
D000818:Animals; D015152:Blotting, Northern; D002467:Cell Nucleus / Q000378:metabolism; D002642:Chick Embryo; D002645:Chickens; D015342:DNA Probes; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D005786:Gene Expression Regulation; D024510:Muscle Development; D009132:Muscles / Q000196:embryology / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000096:biosynthesis; D014158:Transcription, Genetic; D014335:Tropomyosin / Q000235:genetics*
D015342:DNA Probes; D012333:RNA, Messenger; D014335:Tropomyosin; D012321:DNA-Directed RNA Polymerases