Expression pattern of an evolutionarily conserved splice variant in the rat Tacc2 gene.
The transforming acidic coiled-coil containing protein 2 (Tacc2) gene and its paralogs, Tacc1 and Tacc3 encode proteins that are associated with the centrosome and involved in microtubule assembly during the cell cycle. Tacc2 produces several splice variants, which are poorly characterized, especially in the rat. Characterization of the temporal/spatial expression patterns of these isoforms would be useful in understanding their distinct and overlapping functions. By comparative sequence analyses of Tacc2 in multiple species, we identified a third splice variant in rat, which is much shorter in size (1,021 aa) than the longest isoform (2,834 aa). This newly identified Tacc2 splice variant (isoform 3) uses a distinct first exon and generates a different open reading frame. Although Isoform 3 is expressed predominantly during developmental stages, the long Tacc2 isoform (isoform 1) is distributed mainly in adult tissues. Multiple protein sequence analyses revealed that Tacc2 Isoform 3 could be the ancient form, as it is conserved in mammals, birds, and amphibians; whereas the long Tacc2 isoforms may have evolved in the mammalian lineage by adding exons toward the 5' region of the ancient isoform.
Ophthalmology, Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland; Hazard Identification Division, Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada.
Bhaja K
BK
Padhi
J Samuel
JS
Zigler
Piyush
P
Padhi
Stacey
S
Hose
Debasish
D
Sinha
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism*; D017124:Conserved Sequence; D019143:Evolution, Molecular; D005091:Exons; D018507:Gene Expression Regulation, Developmental; D016366:Open Reading Frames; D010802:Phylogeny; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein
D018797:Cell Cycle Proteins; D020033:Protein Isoforms
alterative promoter; alternative splicing; comparative sequence analysis