TY - JOUR
T1 - TRP and the PDZ protein, INAD, form the core complex required for retention of the signalplex in Drosophila photoreceptor cells
AU - Li, Hong Sheng
AU - Montell, Craig
PY - 2000/9/18
Y1 - 2000/9/18
N2 - The light response in Drosophila photoreceptor cells is mediated by a series of proteins that assemble into a macromolecular complex referred to as the signalplex. The central player in the signalplex is inactivation no afterpotential D (INAD), a protein consisting of a tandem array of five PDZ domains. At least seven proteins bind INAD, including the transient receptor potential (TRP) channel, which depends on INAD for localization to the phototransducing organelle, the rhabdomere. However, the determinants required for localization of INAD are not known. In this work, we showed that INAD was required for retention rather than targeting of TRP to the rhabdomeres. In addition, we demonstrated that TRP bound to INAD through the COOH terminus, and this interaction was required for localization of INAD. Other proteins that depend on INAD for localization, phospholipase C and protein kinase C, also mislocalized. However, elimination of any other member of the signalplex had no impact on the spatial distribution of INAD. A direct interaction between TRP and INAD did not appear to have a role in the photoresponse independent of localization of multiple signaling components. Rather, the primary function of the TRP/INAD complex is to form the core unit required for localization of the signalplex to the rhabdomeres.
AB - The light response in Drosophila photoreceptor cells is mediated by a series of proteins that assemble into a macromolecular complex referred to as the signalplex. The central player in the signalplex is inactivation no afterpotential D (INAD), a protein consisting of a tandem array of five PDZ domains. At least seven proteins bind INAD, including the transient receptor potential (TRP) channel, which depends on INAD for localization to the phototransducing organelle, the rhabdomere. However, the determinants required for localization of INAD are not known. In this work, we showed that INAD was required for retention rather than targeting of TRP to the rhabdomeres. In addition, we demonstrated that TRP bound to INAD through the COOH terminus, and this interaction was required for localization of INAD. Other proteins that depend on INAD for localization, phospholipase C and protein kinase C, also mislocalized. However, elimination of any other member of the signalplex had no impact on the spatial distribution of INAD. A direct interaction between TRP and INAD did not appear to have a role in the photoresponse independent of localization of multiple signaling components. Rather, the primary function of the TRP/INAD complex is to form the core unit required for localization of the signalplex to the rhabdomeres.
KW - Drosophila
KW - INAD
KW - PDZ
KW - Phototransduction
KW - TRP
UR - http://www.scopus.com/inward/record.url?scp=0034683664&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034683664&partnerID=8YFLogxK
U2 - 10.1083/jcb.150.6.1411
DO - 10.1083/jcb.150.6.1411
M3 - Article
C2 - 10995445
AN - SCOPUS:0034683664
SN - 0021-9525
VL - 150
SP - 1411
EP - 1421
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 6
ER -