Psychiatry related information on Grik4

• Contrasting effects of electroconvulsive shock on mRNAs encoding the high affinity kainate receptor subunits (KA1 and KA2) and cyclophilin in the rat [1].

High impact information on Grik4

• Although kainate-receptor subunits (GluR5-7, KA1 and 2) are widely expressed in the mammalian central nervous system, little is known about their function [2].
• Kainate receptors are formed from a separate set of genes (GluR5-7, KA-1 and KA-2) and are widely distributed throughout the brain [3].
• The selectively high expression of KA-1 messenger RNA in the CA3 region of the hippocampus closely corresponds to autoradiographically located high-affinity kainate binding sites [4].
• The KA-1 mRNA occurs mainly in the CA3 field of the hippocampus and dentate gyrus, with much lower amounts being found in inner cortical layers, cerebellar Purkinje cells, and white matter (e.g., corpus callosum and anterior commissure) [5].
• We also show that the high-affinity kainate receptor subunits KA1 and KA2 are expressed in central terminals of DRG neurons and are co-expressed with low-affinity receptor subunits in the same terminals [6].

Biological context of Grik4

• Linkage mapping of the interleukin 1beta converting enzyme (Il1bc) and the glutamate receptor subunit KA1 (Grik4) genes to rat chromosome 8 [7].
• In the STR, the gene expression of all KA subunit mRNAs is higher during embryonic development than after birth, except KA1 transcripts, that show a peak at P5 [8].

Anatomical context of Grik4

• This correlation, as well as the particular in vivo pattern of neurodegeneration observed on kainate-induced neurotoxicity, suggests that KA-1 participates in receptors mediating the kainate sensitivity of neurons in the central nervous system [4].
• Neither KA1 nor GluR5 expression was observed in the basal ganglia of adult rats, although these messages were present in other regions [9].
• The relative abundances of KA1 and KA2 were 12 and 88% for cortical neurones, and 19 and 79% for spinal cord neurones, respectively [10].
• During postnatal development, expression of the kainate receptor subunits was characteristically highest on postnatal day 1 and declined to adult levels by day 20; however, in the globus pallidus we did observe the transient expression of KA1 and GluR5 between day 1 and day 10 [9].
• Binding affinities were similar in both cytosols (KA1 approximately 1.5 X 10(9) M-1, KA2 approximately 1 X 10(8) M-1); in contrast, the number of sites was 4-fold smaller in 14-day cytosols [11].

Analytical, diagnostic and therapeutic context of Grik4

• The expression of the five known genes encoding kainate receptor subunits (GluR-5, -6, -7, KA-1, and KA-2) was studied by in situ hybridization during pre- and postnatal development of the rat brain [12].
• Immunohistochemistry against subunits of GluRs reveals GluR6 and KA1-like immunoreactivity [13].

References