TY - JOUR
T1 - Immunohistochemical distribution of RGS7 protein and cellular selectivity in colocalizing with Gαq proteins in the adult rat brain
AU - Khawaja, Xavier Z.
AU - Liang, Jin Jun
AU - Saugstad, Julie A.
AU - Jones, Philip G.
AU - Harnish, Steven
AU - Conn, P. Jeffrey
AU - Cockett, Mark I.
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 1999
Y1 - 1999
N2 - Regulators of G protein signaling (RGS) proteins serve as potent GTPase- activating proteins for the heterotrimeric G proteins αi/o and αq/11. This study describes the immunohistochemical distribution of RGS7 throughout the adult rat brain and its cellular colocalization with Gαq/11, an important G protein-coupled receptor signal transducer for phospholipase Cβ-mediated activity. In general, both RGS7 and Gαq/11 displayed a heterogeneous and overlapping regional distribution. RGS7 immunoreactivity was observed in cortical layers I-VI, being most intense in the neuropil of layer I. In the hippocampal formation, RGS7 immunoreactivity was concentrated in the strata oriens, strata radiatum, mossy fibers, and polymorphic cells, with faint to nondetectable immunolabeling within the dentate gyrus granule cells and CA1- CA3 subfield pyramidal cells. Numerous diencephalic and brainstem nuclei also displayed dense RGS7 immunostaining. Dual immunofluorescence labeling studies with the two protein-specific antibodies indicated a cellular selectivity in the colocalization between RGS7 and Gαq/11 within many discrete brain regions, such as the superficial cortical layer I, hilus area of the hippocampal formation, and cerebellar Golgi cells. To assess the ability of Gαq/11-mediated signaling pathways to modulate dynamically RGS expression, primary cortical neuronal cultures were incubated with phorbol 12,13- dibutyrate, a selective protein kinase C activator. A time-dependent increase in levels of mRNA for RGS7, but not RGS4, was observed. Our results provide novel information on the region- and cell-specific pattern of distribution of RGS7 with the transmembrane signal transducer, Gαq/11. We also describe a possible RGS7-selective neuronal feedback adaptation on Gαq/11-mediated pathway function, which may play an important role in signaling specificity in the brain.
AB - Regulators of G protein signaling (RGS) proteins serve as potent GTPase- activating proteins for the heterotrimeric G proteins αi/o and αq/11. This study describes the immunohistochemical distribution of RGS7 throughout the adult rat brain and its cellular colocalization with Gαq/11, an important G protein-coupled receptor signal transducer for phospholipase Cβ-mediated activity. In general, both RGS7 and Gαq/11 displayed a heterogeneous and overlapping regional distribution. RGS7 immunoreactivity was observed in cortical layers I-VI, being most intense in the neuropil of layer I. In the hippocampal formation, RGS7 immunoreactivity was concentrated in the strata oriens, strata radiatum, mossy fibers, and polymorphic cells, with faint to nondetectable immunolabeling within the dentate gyrus granule cells and CA1- CA3 subfield pyramidal cells. Numerous diencephalic and brainstem nuclei also displayed dense RGS7 immunostaining. Dual immunofluorescence labeling studies with the two protein-specific antibodies indicated a cellular selectivity in the colocalization between RGS7 and Gαq/11 within many discrete brain regions, such as the superficial cortical layer I, hilus area of the hippocampal formation, and cerebellar Golgi cells. To assess the ability of Gαq/11-mediated signaling pathways to modulate dynamically RGS expression, primary cortical neuronal cultures were incubated with phorbol 12,13- dibutyrate, a selective protein kinase C activator. A time-dependent increase in levels of mRNA for RGS7, but not RGS4, was observed. Our results provide novel information on the region- and cell-specific pattern of distribution of RGS7 with the transmembrane signal transducer, Gαq/11. We also describe a possible RGS7-selective neuronal feedback adaptation on Gαq/11-mediated pathway function, which may play an important role in signaling specificity in the brain.
KW - Brain localization
KW - Confocal microscopy
KW - Gαq/11
KW - Immunohistochemistry
KW - Rat
KW - Regulator of G protein signaling 7
UR - http://www.scopus.com/inward/record.url?scp=0032929315&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032929315&partnerID=8YFLogxK
U2 - 10.1046/j.1471-4159.1999.0720174.x
DO - 10.1046/j.1471-4159.1999.0720174.x
M3 - Article
C2 - 9886068
AN - SCOPUS:0032929315
SN - 0022-3042
VL - 72
SP - 174
EP - 184
JO - Journal of neurochemistry
JF - Journal of neurochemistry
IS - 1
ER -