Title: | The TRPC2 channel forms protein-protein interactions with Homer and RTP in the rat vomeronasal organ |
Author(s): | Mast TG; Brann JH; Fadool DA; |
Address: | "Department of Biological Science, The Florida State University, Tallahassee, FL 32306, USA" |
ISSN/ISBN: | 1471-2202 (Electronic) 1471-2202 (Linking) |
Abstract: | "BACKGROUND: The signal transduction cascade operational in the vomeronasal organ (VNO) of the olfactory system detects odorants important for prey localization, mating, and social recognition. While the protein machinery transducing these external cues has been individually well characterized, little attention has been paid to the role of protein-protein interactions among these molecules. Development of an in vitro expression system for the transient receptor potential 2 channel (TRPC2), which establishes the first electrical signal in the pheromone transduction pathway, led to the discovery of two protein partners that couple with the channel in the native VNO. RESULTS: Homer family proteins were expressed in both male and female adult VNO, particularly Homer 1b/c and Homer 3. In addition to this family of scaffolding proteins, the chaperones receptor transporting protein 1 (RTP1) and receptor expression enhancing protein 1 (REEP1) were also expressed. RTP1 was localized broadly across the VNO sensory epithelium, goblet cells, and the soft palate. Both Homer and RTP1 formed protein-protein interactions with TRPC2 in native reciprocal pull-down assays and RTP1 increased surface expression of TRPC2 in in vitro assays. The RTP1-dependent TRPC2 surface expression was paralleled with an increase in ATP-stimulated whole-cell current in an in vitro patch-clamp electrophysiological assay. CONCLUSIONS: TRPC2 expression and channel activity is regulated by chaperone- and scaffolding-associated proteins, which could modulate the transduction of chemosignals. The developed in vitro expression system, as described here, will be advantageous for detailed investigations into TRPC2 channel activity and cell signalling, for a channel protein that was traditionally difficult to physiologically assess" |
Keywords: | "Animals Animals, Newborn Carrier Proteins/genetics/metabolism Cell Membrane/genetics/*metabolism Epithelial Cells/cytology/metabolism Female Homer Scaffolding Proteins Humans Ion Channels/genetics/metabolism Male Membrane Transport Proteins/genetics/metab;" |
Notes: | "MedlineMast, Thomas G Brann, Jessica H Fadool, Debra A eng R15 DC003318-01/DC/NIDCD NIH HHS/ F31 DC006153/DC/NIDCD NIH HHS/ T32 DC00044/DC/NIDCD NIH HHS/ Research Support, N.I.H., Extramural England 2010/05/25 BMC Neurosci. 2010 May 21; 11:61. doi: 10.1186/1471-2202-11-61" |