This family consists of several D1 dopamine receptor-interacting (calcyon) proteins. D1/D5 dopamine receptors in the basal ganglia, hippocampus, and cerebral cortex modulate motor, reward, and cognitive behaviour. D1-like dopamine receptors likely modulate neocortical and hippocampal neuronal excitability and synaptic function via Ca(2+) as well as cAMP-dependent signaling [1]. Defective calcyon proteins have been implicated in both attention-deficit/hyperactivity disorder (ADHD) [2] and schizophrenia [3].

1: D1/D5 dopamine receptors stimulate intracellular calcium release in primary cultures of neocortical and hippocampal neurons. Lezcano N, Bergson C; J Neurophysiol 2002;87:2167-2175. PMID:11929934

2: A genomewide scan for loci involved in attention-deficit/hyperactivity disorder. Fisher SE, Francks C, McCracken JT, McGough JJ, Marlow AJ, MacPhie IL, Newbury DF, Crawford LR, Palmer CG, Woodward JA, Del'Homme M, Cantwell DP, Nelson SF, Monaco AP, Smalley SL; Am J Hum Genet 2002;70:1183-1196. PMID:11923911

3: Up-regulation of the D1 dopamine receptor-interacting protein, calcyon, in patients with schizophrenia. Koh PO, Bergson C, Undie AS, Goldman-Rakic PS, Lidow MS; Arch Gen Psychiatry 2003;60:311-319. PMID:12622665