麩胺酸受器是脊椎動物中樞神經系統主要的興奮性神經傳導物質之受器。離子通道型麩胺酸受器依藥理學與電生理學的性質可分為AMPA受器、Kainate受器及NMDA受器。麩胺酸受器C端區域能夠與細胞內一些蛋白質產生交互作用，影響麩胺酸受器在細胞膜上的數量及穩定性，為了解在斑馬魚發育過程中GluR1a、GluR2a和GluR2b不同C端形式的表現模式，我們以RT-PCR進行分析，結果顯示在斑馬魚發育過程中，GluR1a以GluR1ac RNA的表現為主，而GluR1a/GluR1ac的比例會隨著斑馬魚發育而增加；GluR2a在胚體發育10小時之前，有較多GluR2ac的RNA量，當胚體發育24小時之後，則有較多GluR2a RNA產生；GluR2b/GluR2bc的比例在發育過程中則無明顯變化，以GluR2b RNA表現為主，因此不同C端形式的麩胺酸受器可能多以其中一種形式主要表現於個體中。以RT-PCR和即時定量PCR分析顯示，在胚體發育早期之麩胺酸RNA為maternal RNA，此maternal RNA會隨胚體逐漸發育而減少,在胚體發育8至10小時之間已無法偵測，在胚體發育10小時之後，麩酸受器RNA的量才逐漸增加。然而GluR1a和GluR1b在之後的發育過程中RNA表現的模式並不一致，GluR2a和GluR2b RNA的表現也不盡相同。可能是由於兩個GluR1同源體和GluR2兩個同源體各自具有不同功能，在發育過程中各自具受到不同的機制調控所產生之結果。

Ionotropic glutamate receptors (iGluRs) mediate excitatory synaptic transmission in the vertebrate CNS. Based on pharmacological and electrophysiological criteria, iGluRs have been traditionally classified into three major subtypes: AMPA, kainate, and NMDA receptors. The C-terminus of AMPA receptors is intracellular and is involved in receptor anchoring. In this study, we examined the expression patterns of GluR1a, GluR2a, and GluR2b C-terminal alternative splicing isoforms by RT-PCR. We found that during zebrafish development, the GluR1ac (the long C-terminus isoform) RNA is more abundant than GluR1a (the short C-terminus isoform) at all stages, and the ratio between GluR1a and GluR1ac increases with the development. The GluR2ac (the long C-terminus isoform) RNA is more abundant than GluR2a (the short C-terminus isoform) before 10 hpf, but the GluR2a RNA increases dramatically at 24 hpf and remains as the dominant form thereafter. There is no significant change of RNA expression between GluR2b (the short C-terminus isoform) and GluR2bc (the long C-terminus isoform) at all stages, where GluR2b is the major form. RT-PCR also reveals the existence of maternally transcribed glutamate receptor RNAs, but the amounts of these maternal RNAs decline to a non-detectable level by 8 to 10 hpf. The glutamate receptor RNAs levels then increase gradually after 10 hpf. GluR1a and GluR1b RNAs expression patterns differ at later developmental stages and so do GluR2a and GluR2b. These results show that the gene expression patterns of the paralogous genes differ, suggesting that the functions of these genes may be different.

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