title: Increased complexity of Tmem16a/Anoctamin 1 transcript alternative splicing.
abstract: BACKGROUND
  TMEM16A (Anoctamin 1; ANO1) is an eight transmembrane protein that functions as a calcium-activated chloride channel. TMEM16A in human exhibits alternatively spliced exons (6b, 13 and 15), which confer important roles in the regulation of channel function. Mouse Tmem16a is reported to consist of 25 exons that code for a 956 amino acid protein. In this study our aim was to provide details of mouse Tmem16a genomic structure and to investigate if Tmem16a transcript undergoes alternative splicing to generate channel diversity.
  
  
  RESULTS
  We identified Tmem16a transcript variants consisting of alternative exons 6b, 10, 13, 14, 15 and 18. Our findings indicate that many of these exons are expressed in various combinations and that these splicing events are mostly conserved between mouse and human. In addition, we confirmed the expression of these exon variants in other mouse tissues. Additional splicing events were identified including a novel conserved exon 13b, tandem splice sites of exon 1 and 21 and two intron retention events.
  
  
  CONCLUSIONS
  Our results suggest that Tmem16a gene is significantly more complex than previously described. The complexity is especially evident in the region spanning exons 6 through 16 where a number of the alternative splicing events are thought to affect calcium sensitivity, voltage dependence and the kinetics of activation and deactivation of this calcium-activated chloride channel. The identification of multiple Tmem16a splice variants suggests that alternative splicing is an exquisite mechanism that operates to diversify TMEM16A channel function in both physiological and pathophysiological conditions.
authors.affiliation: Department of Physiology and Cell Biology, 1664 North Virginia Street, University of Nevada School of Medicine, Reno, Nevada 89557-0046, USA.
authors.forename: Kate E
authors.initials: KE
authors.lastname: O'Driscoll
authors.forename: Rachel A
authors.initials: RA
authors.lastname: Pipe
authors.forename: Fiona C
authors.initials: FC
authors.lastname: Britton
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D000075369:Anoctamin-1; D018118:Chloride Channels / Q000235:genetics* / Q000378:metabolism*; D019295:Computational Biology; D005091:Exons; D006801:Humans; D007438:Introns; D051379:Mice; D008969:Molecular Sequence Data
chemical_list: C531181:ANO1 protein, mouse; D000075369:Anoctamin-1; D018118:Chloride Channels