Panel A shows a phylogenetic tree of the TARP branch within the TARP/CACNG/GSG1L gene family, with genes tested in bold. An inset structure displays Rat-TARP2 in complex with Rat-GluA2 AMPAR. Panels B to E present data on the modulation of AMPAR function by different TARPs. Each panel includes example current traces, bar graphs of maximum current amplitude, and line graphs of normalized current amplitude in response to increasing glutamate concentrations. Panel F shows a heatmap of relative RNA expression levels of Hofstenia miamia TARP and AMPAR subunit genes across different cell clusters.
Modulation of AMPAR function by auxiliary proteins. (A) TARP branch of a TARP/CACNG/GSG1L gene tree (full tree in Fig. S6). Genes tested here are in bold. Inset structure (PDB accession no. 5WEO) shows Rat-TARPγ2 in complex with Rat-GluA2 AMPAR. (B–E) Left, example currents; middle, maximum current amplitude (columns—mean, dots—data from different oocytes); and right, mean ± SD (n = 4) current amplitude (normalized to maximum) in response to increasing concentrations of glutamate at oocytes injected with indicated cRNAs: AMPAR alone, or AMPAR with indicated TARP. Sac-TARP-XP…2518 and …6113 in C refer to TARP-XP_006822518.1 and XP_006816113.1. (F) Relative expression of H. miamia TARP (Hof-98036255) and AMPAR subunit (other genes) RNAs in indicated cell clusters from publicly available single-cell RNA sequencing data (Hulett et al., 2023).