Proc Natl Acad Sci U S A. 2003 Mar 4;100(5):2220-5. Epub 2003 Feb 24.

The mouse C-type transient receptor potential 2 (TRPC2) channel: alternative splicing and calmodulin binding to its N terminus.External 2231691f894ba696de1310221b0a0dbbb31a7251e75115c265587c3d9d5f507c

Yildirim, E., Dietrich, A., Birnbaumer, L.,
["Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA."]
Channels of the C-type transient receptor potential (TRPC) are involved in agonist-stimulated and capacitative calcium entry. There are seven TRPCs, all of which have a Ca(2+)-dependent calmodulin (CaM)-binding domain in their C termini. We now tested binding of CaM to TRPC N termini and show that only that of TRPC2 binds CaM in a Ca(2+)-dependent manner. Four TRPC2 cDNAs have been reported: a (also clone 14), b (also clone 17), alpha, and beta. Sequences responsible for CaM binding in TRPC2 a and b are absent from the alpha and beta isoforms. The alpha and beta cDNAs of TRPC2 were reported as alternative forms, when recloning of TRPC2 a and b proved impossible. Here we analyzed total RNA samples from brain and testis for presence of TRPC2 a and b and describe the splicing patterns responsible for their formation, as well as those leading to the alpha and beta forms of TRPC2. We re-assert existence of RNA encoding the TRPC2 a and b, encoded in 21 exons with an initiator ATG in exon 2 for TRPC2a and in exon 4 for TRCP2b. The analysis of alpha and beta TRPC2 cDNAs indicates that although the TRPC2 beta mRNA may exist, the TRPC2 alpha cDNA is derived from an incompletely processed TRPC2a mRNA: It includes in its presumed 5'-untranslated sequence, 713 nt of TRPC2a cDNA fused to 291 nt of an incompletely excised intron. While encoding an active channel in the mouse, the human TRPC2 appears to be a pseudogene. We searched for the human gene in the data bank and located approximately one-half of it in a chromosomal region syntenic to that of the mouse, with similar intron-exon structure. We conclude that the human TRPC2 gene may never have been an active gene because of incomplete ancestral duplication or, if it was complete at one point, that it became inactive upon loss of chromosomal sequences.
PMID: 12601176External 2231691f894ba696de1310221b0a0dbbb31a7251e75115c265587c3d9d5f507c
Validation: In vitro validation Toggle 893349bafcc528f8346c51dc3420151d67b0126b2c122dd1017121c03fa0f69b
  Assay with recombinant proteins Reference
TRP channel construct Interactor construct
TRP channel Interactor Method Species Region Expression system Species Region Expression system
TRPC1 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 Calmodulin Fusion protein-pull down assay Human 1-341 In vitro translation Not specified Full-length E. coli 12601176
TRPC2 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 Calmodulin Fusion protein-pull down assay Mouse 1-619 In vitro translation Not specified Full-length E. coli 12601176
TRPC3 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 Calmodulin Fusion protein-pull down assay Human 1-340 In vitro translation Not specified Full-length E. coli 12601176
TRPC4 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 Calmodulin Fusion protein-pull down assay Mouse 1-320 In vitro translation Not specified Full-length E. coli 12601176
TRPC5 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 Calmodulin Fusion protein-pull down assay Mouse 1-321 In vitro translation Not specified Full-length E. coli 12601176
TRPC6 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 Calmodulin Fusion protein-pull down assay Mouse 1-396 In vitro translation Not specified Full-length E. coli 12601176
(Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4: click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
Characterization Toggle 893349bafcc528f8346c51dc3420151d67b0126b2c122dd1017121c03fa0f69b
  Binding region mapping Stoichiometry Affinity (Kd) Reference
TRP channel Interactor
TRP channel Interactor Method Species Region Species Region
TRPC2 Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4 Calmodulin Fusion protein-pull down assay Mouse 104-195 Not specified Not determined 12601176
(Link 2bd4d11adb659cddf58197a94e201f0a44c55d8d7cb427c624971b42e122c0a4: click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
TRP / Interactor

To prevent spam comments, we use reCAPTCHA. Please type correct words into the following box.