Nucleotide Sequence and Expression of a cDNA Encoding Canine Carbonic Anhydrase VI (CA-VI)

Abstract

A full-length cDNA clone of a canine carbonic anhydrase VI (CA-VI) was generated from the canine parotid gland by using a reverse transcription-polymerase chain reaction (RT-PCR) technique with degenerate primers designed from conserved regions of the same locus in humans and bovines employing RACE (rapid amplification of cDNA ends) techniques. The cDNA sequence was 1351 base pairs (bp) long and was predicted to encode a 320-amino-acid polypeptide containing a putative signal peptide of 17 amino acids. The deduced amino acid sequence of mature CA-VI showed the highest similarity of 74% to that of human CA-VI. RT-PCR analysis with primers specific to the canine CA-VI demonstrated strong signals in the major salivary glands and weak signals in the minor salivary glands and esophagus of a healthy dog. No CA-VI mRNA was detected in the pancreas, liver or the digestive tract except the esophagus.

Gene expression profiling in the submandibular gland, stomach, and duodenum of CAVI-deficient mice

“…It is secreted into saliva by serous acinar cells of the parotid, submandibular (Parkkila et al 1990), and lingual von Ebner's glands (Amasaki et al 2003;Leinonen et al 2001) and into milk by the mammary glands (Karhumaa et al 2001). Recently this enzyme has been found in the lacrimal glands (Ogawa et al 2002), nasal, septal, and lateral glands (Kimoto et al 2004), esophagus (Kasuya et al 2007;Murakami et al 2003), tracheobronchial glands, epithelial serous cells (Leinonen et al 2004), and alimentary canal (Kaseda et al 2006). Low concentrations of CAVI have also been detected in serum (Kivela et al 1997).…”

Determination of Full-Length cDNA Nucleotide Sequence of Equine Carbonic Anhydrase VI and Its Expression in Various Tissues

“…There were some differences in CA6 expression between species. In dog, CA6 was not detected in the lower alimentary tract including stomach, jejunum, ileum and colon in RT-PCR study [15]. In equine alimentary tract, CA-VI expression was confirmed in both small and large intestine as indicated Fig.…”

“…Although a lot information on CA-VI is accumulating, little is known on that of equine family. Interestingly, there were some differences of expressional pattern in alimentary tracts between species [10,15]. Until now, several mammalian CA6 cDNAs have been cloned successfully [1,8,14,16], though that of equine remains to be determined.…”

“…Among other isozymes, CA-VI is a unique secretory type that was discovered in the ovine parotid gland and saliva [4], and it was first purified by Feldstein and Silverman from rat saliva [3]. CA-VI is well known to be involved in regulating pH of saliva and protecting the upper alimentary canal against excess acidity [15]. It is also demonstrated that CA-VI is secreted by seromucous tracheobronchial glands, the serous epithelial cells of the trachea and bronchi, and by the Clara cells of the bronchium [13].…”

Immunohistolocalization and Gene Expression of Secretory Carbonic Anhydrase Isoenzyme CA-VI in Canine Nasal Cavity

“…At least 14 distinct active isoenzymes of CA are widely distributed throughout mammalian organs [11]. Of these isoenzymes, only CA-VI occurs in secreted form, and it localizes to the digestive organs, specifically the parotid, submandibular and esophageal, lingual serous von Ebner's glands in sheep [8,9,31], rats [7,18,23], humans [13,18,20,24,29] and dogs [2,14,21]. Furthermore, the CA-VI isoenzyme has been identified in the lacrimal and mammary glands of rats [26], sheep [25] and cattle [12,16].…”