Anti-sense-mediated inhibition of expression of the novel striated tropomyosin isoform TPM1kappa disrupts myofibril organization in embryonic axolotl hearts.
Striated muscle tropomyosin (TM) is described as containing ten exons; 1a, 2b, 3, 4, 5, 6b, 7, 8, and 9a/b. Exon 9a/b has critical troponin binding domains and is found in striated muscle isoforms. We have recently discovered a smooth (exon 2a)/striated (exons 9a/b) isoform expressed in amphibian, avian, and mammalian hearts, designated as an isoform of the TPM1 gene (TPM1kappa). TPM1kappa expression was blocked in whole embryonic axolotl heart by transfection of exon-specific anti-sense oligonucleotide. Reverse transcriptase polymerase chain reaction (RT-PCR) confirmed lower transcript expression of TPM1kappa and in vitro analysis confirmed the specificity of the TPM1kappa anti-sense oligonucleotide. Altered expression of the novel TM isoform disrupted myofibril structure and function in embryonic hearts.
Zajdel
Robert W
RW
Department of Cell and Developmental Biology, Upstate Medical University, 750 East Adams Street, Syracuse, New York 13210, USA.
Denz
Christopher R
CR
Narshi
Aruna
A
Dube
Syamalima
S
Dube
Dipak K
DK
D000557:Ambystoma / Q000196:embryology*; D000818:Animals; D006321:Heart / Q000196:embryology*; D018613:Microscopy, Confocal; D009206:Myocardium / Q000378:metabolism*; D009210:Myofibrils / Q000737:chemistry / Q000378:metabolism*; D016376:Oligonucleotides, Antisense / Q000235:genetics / Q000378:metabolism*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014335:Tropomyosin / Q000235:genetics* / Q000378:metabolism*
D016376:Oligonucleotides, Antisense; D020033:Protein Isoforms; D012333:RNA, Messenger; D014335:Tropomyosin