High impact information on LOC396300

• This raises the possibility, that kainate binding protein may form part of an ion channel and may be a subunit of a kainate subtype of glutamate receptor [1].
• As a result, we present here the subsets of amino acids accounting for the binding free energies and specificities of KBP for kainate, glutamate, and CNQX and propose a three-dimensional model, at the microarchitectural level, of the glutamatergic binding domain [2].
• Accordingly, we propose that the glycine-rich motif of KBP forms part of a guanine nucleotide binding site [3].
• Site-directed mutagenesis of residues K72 and Y73 within the glycine-rich motif followed by the expression of the KBP mutants at the surface of HEK 293 cells showed a decrease in GTP binding affinity by factors of 10 and 100 respectively [3].
• Here, we report that guanine, but not adenine, nucleotides interact with KBP by inhibiting [3H]KA binding in a competitive-like manner, displaying IC50 values in the micromolar range [3].

Biological context of LOC396300

• To locate the GTP binding site, KBP was photoaffinity labelled with [alpha-32P]GTP [3].
• The chick cerebellar kainate (KA) binding protein (KBP), a member of the family of ionotropic glutamate receptors, harbours a glycine-rich (GxGxxG) motif known to be involved in the binding of ATP and GTP to kinases and G proteins respectively [3].
• We interpret our findings to indicate the requirement for a modulatory protein or an additional subunit serving to alter the structure of the KBP subunit complex such that signal transduction is enabled from the ligand binding site to the intrinsically functional ion pore [4].
• The gene encoding the chick kainate binding protein undergoes a glutamate-dependent transcriptional regulation via an activator protein-1 site within its promoter region [5].
• Finally, the activator protein-1 complex binds to the glutamate response element in the chick kainate binding protein promoter region inducing its activity [5].

Anatomical context of LOC396300

• Membranes prepared from the culture cells displayed, using 25 nM [3H]kainate, the binding of 4.1 pmol of [3H]kainate/mg protein and showed the presence in Western blots of the two polypeptides of 49 and 93 kDa attributed to the kainate binding protein [6].
• In this study, we have analysed the anatomical and subcellular distribution of the alpha-amino-3-hydroxyl-5-methyl-isoxazole-4-propionate receptors in the rat hippocampus and cerebellum, using a monoclonal antibody that was raised against a kainate binding protein purified from frog brain [7].
• The association of Bergmann glial processes, carrying the Mr = 49,000 kainate binding protein, with the Purkinje cell dendrites and spine synapses could provide a basis for neuronal signalling to the Bergmann glia, possibly by glutamate [8].

Associations of LOC396300 with chemical compounds

• Taking advantage of the fact that the gene encoding the chick kainate-binding protein undergoes a glutamate-dependent transcriptional regulation via an activator protein-1 (AP-1) site, we evaluated the involvement of tyrosine kinases in this process [9].

References