Temporal and regional expression of NMDA receptor subunit NR3A in the mammalian brain.
NR3A is a developmentally regulated N-methyl-D-aspartate receptor (NMDAR) subunit that was previously known as NMDAR-L or chi-1. Unlike other NMDAR subunits, NR3A inhibits the NMDAR-associated ion channel in a novel manner, and a role in synaptogenesis has been suggested for this subunit. Here, we report a comprehensive study to delineate the temporal and anatomic expression of NR3A protein in the mammalian brain by using a monoclonal anti-NR3A antibody. NR3A protein was found to peak at postnatal day (P) 8, and to decrease gradually from P12 to adulthood in the rat central nervous system. Moreover, NR3A protein was heavily expressed in all areas of the isocortex, portions of the amygdaloid nuclei, and selective cell layers and nuclei of the hippocampus, thalamus, hypothalamus, brainstem, and spinal cord. NR3A protein was also expressed in the cerebellar cortex, whereas only weak signal was detected in the previous in situ studies by using riboprobes. At an ultrastructural level, NR3A was associated specifically with asymmetrical synapses and localized to postsynaptic membranes. This information will facilitate future research on NMDARs by providing clues to possible inclusion of the NR3A subunit in NMDARs in many brain regions.
Wong
Hon-Kit
HK
Department of Biology and Biotechnology Research Institute, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.
Liu
Xiao-Bo
XB
Matos
Maria F
MF
Chan
Shing Fai
SF
Pérez-Otaño
Isabel
I
Boysen
Megan
M
Cui
Jiankun
J
Nakanishi
Nobuki
N
Trimmer
James S
JS
Jones
Edward G
EG
Lipton
Stuart A
SA
Sucher
Nikolaus J
NJ
D000818:Animals; D001921:Brain / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D002478:Cells, Cultured; D002574:Cervical Vertebrae / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007668:Kidney / Q000378:metabolism; D009928:Organ Specificity; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000096:biosynthesis* / Q000737:chemistry; D013116:Spinal Cord / Q000166:cytology / Q000378:metabolism
C464437:NR3A NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate