title: Isolation and sequencing of swine carbonic anhydrase VI, an enzyme expressed in the swine kidney.
abstract: BACKGROUND
  Carbonic anhydrase VI (CA-VI) is produced by the salivary gland and is secreted into the saliva. Although CA-VI is found in the epithelial cells of distal straight tubule of swine kidneys, the exact function of CA-VI in the kidneys remains unclear.
  
  
  RESULTS
  CA-VI was located in the epithelial cells of distal straight tubule of swine kidneys.A full-length cDNA clone of CA-VI was generated from the swine parotid gland by reverse transcription polymerase chain reaction, using degenerate primers designed based on conserved regions of the same locus in human and bovine tissues. The cDNA sequence was 1348 base pairs long and was predicted to encode a 317 amino acid polypeptide with a putative signal peptide of 17 amino acids. The deduced amino acid sequence of mature CA-VI was most similar (77.4%) to that of human CA-VI. CA-VI expression was confirmed in both normal and nephritic kidneys, as well as parotid. As the primers used in this study spanned two exons, the influence of genomic DNA was not detected. The expression of CA-VI was demonstrated in both normal and nephritic kidneys, and mRNA of CA-VI in the normal kidneys which was the normalised to an endogenous β-actin was 0.098 ± 0.047, while it was significantly lower in the diseased kidneys (0.012 ± 0.007). The level of CA-VI mRNA in normal kidneys was 19-fold lower than that of the parotid gland (1.887).
  
  
  CONCLUSIONS
  The localisation of CA-VI indicates that it may play a specialised role in the kidney.
authors.affiliation: Laboratory of Physiology I, School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Sagamihara, Kanagawa 252-5201, Japan. nishida@azabu-u.ac.jp.
authors.forename: Toshiho
authors.initials: T
authors.lastname: Nishita
authors.forename: Juro
authors.initials: J
authors.lastname: Yatsu
authors.forename: Masaru
authors.initials: M
authors.lastname: Murakami
authors.forename: Shino
authors.initials: S
authors.lastname: Kamoshida
authors.forename: Kensuke
authors.initials: K
authors.lastname: Orito
authors.forename: Nobutune
authors.initials: N
authors.lastname: Ichihara
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Arishima
authors.forename: Hideharu
authors.initials: H
authors.lastname: Ochiai
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002256:Carbonic Anhydrases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004847:Epithelial Cells / Q000201:enzymology / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D007150:Immunohistochemistry; D007686:Kidney Tubules, Distal / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009393:Nephritis / Q000201:enzymology / Q000235:genetics; D010306:Parotid Gland / Q000201:enzymology / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013552:Swine
chemical_list: D018076:DNA, Complementary; D002256:Carbonic Anhydrases; C477051:carbonic anhydrase VI