First Author | Beisel KW | Year | 1994 |
Journal | Gene | Volume | 143 |
Issue | 2 | Pages | 251-6 |
PubMed ID | 8206382 | Mgi Jnum | J:18728 |
Mgi Id | MGI:66967 | Doi | 10.1016/0378-1119(94)90105-8 |
Citation | Beisel KW, et al. (1994) Identification of novel alternatively spliced isoforms of the tropomyosin-encoding gene, TMnm, in the rat cochlea. Gene 143(2):251-6 |
abstractText | Analysis of a rat cochlear cDNA library for the expression of the non-muscle (nm) tropomyosin (TM)-encoding gene (TMnm), demonstrated that four nm isoforms were present. These four TMnm variants are NM-1, NM-2, NM-3 and NM-4. Nucleotide (nt) sequencing revealed that all these isoforms expressed the nm exon 1b sequence, but varied in their usage of the alternatively spliced exons 6a and b and 9a/b and d, representing skeletal muscle (sk) (exons 6b and 9a/b) and nm (6a and 9d) sequences. A novel exon 9 (designated as exon 9c) was associated with the NM-4 isoform and was also found to be expressed in the cochlea. Comparisons of the nt and amino acid (aa) sequences demonstrated a high homology between rat, mouse and human sequences encoding the 'classical' nm isoform, TM30nm, which is designated herein as NM-1. The rat NM-1 nt homology with mouse and human sequences also included the 3' untranslated region. Homologies were found between aa sequences of the C termini of NM-1 and the TM alpha smooth muscle and TM beta nm isoforms, between the sk sequence of NM-3 and the TM alpha and beta sk isoforms, and between the novel 9c sequence of NM-4 and the TM alpha brain-1 isoform. These data predict that the nm isoforms share biochemical properties described for the other TM isoforms. |