%0 Journal Article %T Expression of Tropomyosin 2 Gene Isoforms in Human Cardiac Tissue %A Bernard J Poiesz %A Dipak K Dube %A Joseph Lachant %A Lynn Abbott %A Patricia Benz %A Santhi Yalamanchili %A Syamalima Dube %J Cardiology and Research (IJCRR) %D 2018 %R http://dx.doi.org/10.19070/2470-4563-140003 %X Previous studies have shown that although the transcript levels of TPM1¦Á and TPM1¦Ê are expressed in human hearts in comparable levels, the level of TPM1¦Á protein is ~90%. The proteins of TPM1¦Ê and TPM2¦Á are about 5% of the total sarcomeric TM. The TPM2 gene is known to generate three alternatively spliced isoforms, which are designated as TPM2¦Á TPM2¦Â TPM2¦Ã. The expression level of TPM2¦Â and TPM2¦Ã in human hearts is unknown. Using a series of primers pairs and probes for RNA PCR, we found that both TPM2¦Á and ¦Â but not ¦Ã were expressed in fetal and adult heart tissue, with about the same amounts of each isoform in fetal hearts and more ¦Â than ¦Á in adult hearts. Four new isoforms of TPM2 RNA were identified (TPM2¦Ä-¦Ç). Most of these were present in very small amounts in both the fetal and adult hearts with the exception of TPM2¦Î, which was present at about 40% of the level of TPM2¦Á in adult heart tissue. Western blot analyses using a series of anti-tropomyosin antibodies indicate that TPM2 protein is present in both fetal and adult hearts at about the same levels as TPM1¦Ê and much less than TPM1¦Á. We are unsure about the expression of TPM2¦Ä, TPM2¦Æ, and TPM2¦Ç proteins in fetal and adult human hearts. The exact function of these new TPM2 isoforms in heart and their role(s) in cardiac disease remain to be elucidated %K n/a %U https://scidoc.org/IJCRR-2470-4563-01-301.php