Referenced in: none

Automatically associated channels: TRP , TRPV , TRPV5 , TRPV6

Title: Tissue-specific expression of the calcium transporter genes TRPV5, TRPV6, NCX1, and PMCA1b in the duodenum, kidney and heart of Equus caballus.

Authors: Inho Hwang, Eui-Man Jung, Hyun Yang, Kyung-Chul Choi, Eui-Bae Jeung

Journal, date & volume: J. Vet. Med. Sci., 2011 Nov , 73, 1437-44

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/21737966

Abstract
Calcium transporter genes, such as transient receptor potential cation channel subfamily V members 5/6 (TRPV5/6), Na(+)/Ca(2+) exchanger 1 (NCX1), and plasma membrane calcium-transporting ATPase 1b (PMCA1b), are essential for maintaining homeostasis and metabolizing Ca(2+) ions. The TRPV5 and TRPV6 proteins play an important role in Ca(2+ )absorption, and NCX1 and PMCA1b are both critical for intracellular calcium homeostasis. In this study, the tissue-specific mRNA and protein expression of these calcium transporter genes in the duodenum, kidney and heart of the horse (Equus caballus) was examined using reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis. The tissue localization of these calcium transporters was also investigated using immunohistochemistry. The results showed that TRPV5 mRNA was highly expressed in the kidney but was scarce in the duodenum and heart. TRPV6 mRNA levels were similar in all the tissues. NCX1 and PMCA1b were both highly expressed in the heart, but no difference in NCX1 and PMCA1b mRNA expressions was observed in the duodenum and kidney. The aspect of protein expression was similar with mRNA expression data. Localization of calcium transporter genes were detected enterocytes in duodenum, the distal convoluted tubules in the kidney, and within the cardiac muscle cells of the heart. Based on these results, calcium transport genes appear to be expressed in horse tissues at levels similar to those observed in other vertebrates.