Induction of TRPV5 expression by small activating RNA targeting gene promoter as a novel approach to regulate cellular calcium transportation

Life Sci. 2014 Oct 2;114(2):70-6. doi: 10.1016/j.lfs.2014.08.007. Epub 2014 Aug 17.

Abstract

Aim: Promoter-targeted small activating RNAs (saRNAs) have been shown to be able to induce target gene expression, a mechanism known as RNA activation (RNAa). The present study tested whether saRNA can induce the overexpression of TRPV5 in human cells derived from the kidney and subsequently manipulate cell calcium uptake.

Main methods: Three saRNAs complementary to the TRPV5 promoter were synthesized and transfected into cells. TRPV5 expression at the RNA and protein levels was analyzed by quantitative real-time PCR and Western blotting respectively. For functional study, transcellular Ca(2+) transportation was tested by fura-2 analysis. Dihydrotestosterone (DHT), a suppressor of cellular calcium transportation, was administered to challenge the activating effect of selected saRNA.

Key findings: One of these synthesized saRNAs, ds-2939, significantly induced the expression of TRPV5 at both mRNA and protein levels. Fura-2 analysis revealed that the intracellular Ca(2+) concentration was elevated by ds-2939. DHT treatment reduced transmembrane Ca(2+) transport, which was partially antagonized by ds-2939.

Significance: Our results suggest that a saRNA targeting TRPV5 promoter can be utilized to manipulate the transmembrane Ca(2+) transport by upregulating the expression of TRPV5 and may serve as an alternative for the treatment of Ca(2+) balance-related diseases.

Keywords: Gene promoter; RNAa; TRPV5; Transmembrane Ca(2+) transport.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Biological Transport / drug effects
  • Biological Transport / physiology
  • Blotting, Western
  • Calcium / metabolism*
  • DNA Primers / genetics
  • Dihydrotestosterone / pharmacology
  • Fluorescent Antibody Technique
  • Fura-2
  • Gene Expression Regulation / genetics*
  • HEK293 Cells
  • Humans
  • Promoter Regions, Genetic / genetics*
  • RNA / genetics
  • RNA / metabolism*
  • Real-Time Polymerase Chain Reaction
  • TRPV Cation Channels / genetics
  • TRPV Cation Channels / metabolism*

Substances

  • DNA Primers
  • TRPV Cation Channels
  • TRPV5 protein, human
  • Dihydrotestosterone
  • RNA
  • Calcium
  • Fura-2