Int. J. Dev. Biol. 43: 175 - 178 (1999)

Vol 43, Issue 2

Differential expression of two skeletal muscle beta-tropomyosin mRNAs during Xenopus laevis development

Published: 1 March 1999

C Gaillard, H Lerivray, N Thézé, B Cooper, D Lepetit, T Mohun and P Thiébaud

ISREC, Epalinges/Lausanne, Switzerland.

Abstract

A cDNA clone for a Xenopus laevis skeletal muscle beta-tropomyosin (beta-TMad) isoform was isolated from an adult skeletal muscle cDNA library. Sequence analysis revealed that this clone corresponded to a second beta-tropomyosin mRNA distinct from the one that was previously characterized (beta-TMemb). The two skeletal beta-TM mRNAs originate from distinct genes and are differentially expressed during development. Beta-TMemb mRNA is expressed only in the somites of the early embryo while beta-TMad mRNA is expressed in pre-metamorphic tadpoles and adult skeletal muscles. We have isolated the promoter region of the beta-TMemb gene and shown that a DNA construct containing 2.9 kb of promoter region is properly expressed after injection in the embryo.