Expression of the eight AMPA receptor subunit genes in the developing central nervous system and sensory organs of zebrafish

Abstract

The AMPA type glutamate receptors mediate the majority of fast synaptic transmission in the vertebrate nervous system. Whereas mammals have four subunit genes, Gria1-4, zebrafish has retained a duplicated set of eight genes named gria1-4a and b. We give here a detailed overview of the expression patterns of all eight zebrafish subunits within the developing central nervous system and sensory organs at 24, 48, and 72 hr after fertilization. Expression domains include distinct neuronal subsets in the developing forebrain, midbrain, hindbrain, and spinal cord, as well as in the ganglion-and inner nuclear layers of the retina. As a general rule, each pair of duplicated gria genes is differentially expressed, indicating subfunctionalization of AMPA receptor subunit expression in the teleost lineage. Our findings suggest that zebrafish can serve as a useful model system to investigate the role of AMPA receptors and their differential expression in the vertebrate nervous system. Developmental Dynamics 237:788 -799, 2008.

Zebrafish Adar2 Edits the Q/R Site of AMPA Receptor Subunit gria2α Transcript to Ensure Normal Development of Nervous System and Cranial Neural Crest Cells

“…In general, the expression domains of adar2 in the CNS and cranial sensory neurons overlapped with that of the AMPAR subunit genes, gria1-4 [18]. However, the spatiotemporal expression patterns of adar2 and gria2α , a homologue of gria2 and a putative substrate of Adar2, were not identical.…”

“…Robust expression of adar2 in the retina and cranial ganglia, especially the posterior lateral line ganglion/placode, started at 24 hpf (Fig. 1G), earlier than an overt expression of gria2α in these regions [18]. After 36 hpf, the adar2 expression in the spinal cord and medulla oblongata diminished, while gria2α expression persisted (Fig.…”

“…The fractions of gria2α R present in the 12-hpf wild type embryos varied from 50% to 65%, while it was between 96 to 98% in the 24-hpf and 48-hpf wild type embryos [18]. Values are represented as means ± standard deviation (number of independent injection).…”

Orexin-A influences mRNA expression of some glutamatergic receptor subtypes inCarassius auratus(Actinopterygii: Cyprinidae)

“…Thus, due to the feasibility of evaluating molecular transcriptional events on partial and not on full-length sequences, nucleotidic and aa homologies of NR1 and GluR2 of our fish model were only compared to those of phylogenetically stable and well-defined sequences of the rat rather than fish, which instead show high gene variability. Indeed, genome-wide gene duplications like those characterizing iGluRs (Hoppmann et al 2008) have been well documented in several teleost species, above all in view of their ability to favor rapid evolution in this vertebrate class rather than in tetrapods (Nikinmaa & Rytkonen 2012). Moreover, the presence of a novel splice cassette containing asparagine, threonine, serine and glycine aa in the crucian carp may create further discrepancies when sequences are compared within fish species like those of the crucian carp and pufferfishes that show only moderate degrees of similarity (Ellefsen et al 2008).…”

In Vivo Imaging of Synaptogenesis in Zebrafish

“…N-cadherin-GFP is also postsynaptic, but has not yet been used as a postsynaptic marker. Again, most of the common postsynaptic molecules have either been cloned (e.g., the NMDA receptor and AMPA receptor subunits; Cox et al 2005;Hoppmann et al 2008) or are easily accessible through database searches (e.g., neuroligins).…”