Figure 5. Summary of glutamate receptor and transporter gene expression in rod bipolar cells

For AMPA-sensitive subunits, nearly every cell expressed the GluR4 gene (23/27), followed by GluR2 (16/27), and GluR1 (11/27). In addition to mGluR6, 24 cells also expressed an additional mGluR gene, most often mGluR3 (20/27). Nearly every rod bipolar cell also expressed the gene for the EAAT2 (23/27) and EAAT4 (21/27) transporter. Expression of kainate subunit genes (GluR5-7, KA1-2) was limited to GluR6 in 4/27 cells, so these are not represented.