Abstract
Purpose::
TRP family channels are cation channels, mostly of rather low selectivity, which play important role in a wide range of sensory systems. Our goal is to identify members of this family expressed in the mammalian retina and identify those important for retinal function.
Methods::
PCR amplification of cDNA across exon junctions was used as an initial screen for transcripts present in mouse retinal mRNA. Northern blotting was used to estimate relative levels of different transcripts, and in situ hybridization is being used to identify the locations of the transcripts.
Results::
With only a few exceptions, transcripts for virtually all TRP family channels encoded in the mouse genome were amplified from retinal cDNA by PCR. Northern blot analysis suggested that the most abundant transcripts are those for TRPC1 and TRPP2, which have been reported to bind to one another in other systems. Strong signals were also observed for two splice variants of TRPM1 and for TRPM3. All of these messages are more abundant in the retina than in the brain. Clear signal was also observed for TRPC3, two splice variants of TRPC4, TRPC5, TRPC6, and TRPV2. The abundance of all of these in the retina is comparable to or somewhat lower than their abundance in brain.
Conclusions::
Multiple TRP family channels are expressed in the mammalian retina. It is likely that they play important roles in retinal function.
Keywords: retina • ion channels • in situ hybridization