RESEARCH ABSTRACT
Striated muscle tropomyosin is classically described as consisting of 10 exons, 1a, 2b, 3, 4, 5, 6b, 7, 8, and 9a/b, in both skeletal and cardiac muscle. Experiments in our laboratory have demonstrated expression of a naturally occurring chimeric isoform of tropomyosin that has both smooth and striated muscle exons. The chimeric isoform has a replacement of exon 2a for 2b that is commonly found in striated isoforms. GFP constructs were used to demonstrate translation and incorporation into organized myofibrils. Antisense oligonucleotide transfection decreased the expression of this isoform and disrupted organization and function.
Selected References
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