First Author | Cox WG | Year | 1995 |
Journal | Differentiation | Volume | 58 |
Issue | 4 | Pages | 269-80 |
PubMed ID | 7641978 | Mgi Jnum | J:25768 |
Mgi Id | MGI:73480 | Doi | 10.1046/j.1432-0436.1995.5840269.x |
Citation | Cox WG, et al. (1995) Cardiac myosin heavy chain expression during heart development in Xenopus laevis. Differentiation 58(4):269-80 |
abstractText | Muscle-specific gene expression in the heart during Xenopus development was investigated using reverse transcription-polymerase chain reaction (RT-PCR) and whole-mount in situ hybridization to detect transcripts of the gene for the cardiac myosin heavy chain (CMHC). RT-PCR analysis determined that CMHC transcripts are present in the cardiac mesoderm at state 13, demonstrating that muscle-specific gene expression in the primitive myocardium has begun by the early neurula stage, approximately 30 h before the heart beat begins. Xenopus, therefore, is similar to amniotes and mammals in that cardiac precursor cells begin to express muscle-specific gene transcripts soon after commitment to the cardiac myocyte lineage. The earliest CMHC gene transcripts can be detected in the heart using whole-mount in situ hybridization is early tailbud stage 28, which coincides with the onset of heart tube morphogenesis. CMHC gene expression was also detected in skeletal muscle: RT-PCR analysis determined that CMHC transcripts are transiently expressed in the somite during the initial phases of skeletal muscle differentiation. Furthermore, CMHC mRNAs are expressed in a subset of head muscles of the feeding tadpole. CMHC gene expression is induced in ectodermal cells of the animal cap in blastula-stage embryos injected with synthetic MyoD or Myf5 RNA, suggesting that the CMHC gene contains regulatory elements that are responsive to the activity of those skeletal-muscle-specific transcription factors. |