TY - JOUR
T1 - Identification of novel alternatively spliced isoforms of the tropomyosin-encoding gene, TMnm, in the rat cochlea
AU - Beisel, Kirk W.
AU - Kennedy, Jane E.
N1 - Funding Information:
We kindly thankD rs. D. Cosgrove,W . Kimberlinga nd S. Smith for their critical reviewo f the manuscriptT. his work was supportedi n part by the DeafnessR esearch Foundation.
PY - 1994/6/10
Y1 - 1994/6/10
N2 - 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 TMa smooth muscle and TMβ nm isoforms, between the sk sequence of NM-3 and the TMα and β sk isoforms, and between the novel 9c sequence of NM-4 and the TMα brain-1 isoform. These data predict that the nm isoforms share biochemical properties described for the other TM isoforms.
AB - 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 TMa smooth muscle and TMβ nm isoforms, between the sk sequence of NM-3 and the TMα and β sk isoforms, and between the novel 9c sequence of NM-4 and the TMα brain-1 isoform. These data predict that the nm isoforms share biochemical properties described for the other TM isoforms.
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U2 - 10.1016/0378-1119(94)90105-8
DO - 10.1016/0378-1119(94)90105-8
M3 - Article
C2 - 8206382
AN - SCOPUS:0028359143
VL - 143
SP - 251
EP - 256
JO - Gene
JF - Gene
SN - 0378-1119
IS - 2
ER -