Fig. 9.

GABA and acetylcholine receptor subtypes identified in C. borealis and H. americanus transcriptome assemblies. Trees were generated as described in Fig. 6. GABA and acetylcholine are both small molecule transmitters in crabs and lobsters. Both transmitters act through ionotropic and metabotropic receptor subtypes. Metabotropic GABA receptors (GABA_B-type) and ionotropic GABA subunits (GABA_A-type) were identified in both species. A comprehensive list of GABA receptor subtypes, including accession numbers, is provided in Table 3. Both nicotinic (ionotropic) and muscarinic (metabotropic) acetylcholine receptors were identified from both species, including one nicotinic beta-subunit and 8 alpha-subunit types. A comprehensive list of acetylcholine receptor subtypes, including accession numbers, is provided in Table 4