title: Species and tissue differences in the expression of DPPY splicing variants.
abstract: The non-functional dipeptidyl peptidase, DPPY (DPP10), regulates the expression and gating of K+ channels in Kv4 family by tightly binding to these pore-forming subunits. Neural tissue-specific expression of this and the related DPPX (DPP6) is thought to confer rapid inactivation and other unique properties of neuronal Kv4 channels. Here we report that DPPY mRNA is abundant in human adrenal gland, but very low in the corresponding rat tissue. Furthermore, multiple DPPY splicing variants with alternative first exons are significant in the brain, whereas the expression of DPPY gene in the adrenal gland and pancreas is predominantly initiated at the two latter sites. These splicing variants, as well as an N-terminal peptide-deleted DPPY, produce similar changes in Kv4.3 gating. Thus, transcription of DPPY gene is species- and tissue-specifically controlled.
authors.affiliation: Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15260, USA. koichi@pitt.edu
authors.forename: Koichi
authors.initials: K
authors.lastname: Takimoto
authors.forename: Yukio
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Ren
authors.forename: Naoki
authors.initials: N
authors.lastname: Yoshimura
mesh_terms: D000311:Adrenal Glands / Q000378:metabolism; D000328:Adult; D000368:Aged; D017398:Alternative Splicing / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000096:biosynthesis* / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics; D009928:Organ Specificity / Q000235:genetics; D010179:Pancreas / Q000378:metabolism; D010447:Peptide Hydrolases / Q000096:biosynthesis / Q000235:genetics; D015221:Potassium Channels / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D013045:Species Specificity
chemical_list: D007527:Isoenzymes; D009419:Nerve Tissue Proteins; D015221:Potassium Channels; D012333:RNA, Messenger; C503535:DPP6 protein, human; D010447:Peptide Hydrolases; C476879:DPP10 protein, human; C557320:DPP6 protein, rat; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases