Expression of a novel tropomyosin isoform in axolotl heart and skeletal muscle.

TPM1kappa is an alternatively spliced isoform of the TPM1 gene whose specific role in cardiac development and disease is yet to be elucidated. Although mRNA studies have shown TPM1kappa expression in axolotl heart and skeletal muscle, it has not been quantified. Also the presence of TPM1kappa protein in axolotl heart and skeletal muscle has not been demonstrated.

Expression of Nkx2.5 in wild type, cardiac mutant, and thyroxine-induced metamorphosed hearts of the Mexican axolotl.

Nkx2.5, a homeodomain-containing transcription factor, is known to be necessary for normal heart development in vertebrates. It is one of the earliest lineage-restricted genes expressed in cardiovascular progenitor cells and knowledge of its expression patterns has important therapeutic implications for damaged cardiomyocytes.

Differential expression of tropomyosin during segmental heart development in Mexican axolotl.

The Mexican axolotl, Ambystoma mexicanum, serves as an intriguing model to investigate myofibril organization and heart development in vertebrates. The axolotl has a homozygous recessive cardiac lethal gene "c" which causes a failure of ventricular myofibril formation and contraction. However, the conus of the heart beats, and has organized myofibrils.