Figure 1.

A, Predicted protein sequence homology and relative expression profile of CACHD1 and α2δ-1. CACHD1 and α2δ-1 subunits both contain a N-terminal signal peptide, a VWA domain, two cache domains, and transmembrane and intracellular domains. GBP, Gabapentin binding domain (RRR); GBP*, gabapentin binding domain variant (RSR); MIDAS, metal-ion-dependent adhesion site (DxSxS); MIDAS*, Metal-ion-dependent adhesion site variant (DxGxS); Cache, Ca²⁺ channel and chemotaxis receptor; TM, transmembrane domain; Cys, cysteine; His, histidine (locations of domains are approximate and from data from www.Uniprot.org, figure drawn using DOG: Domain Graphics). B, Relative expression profile of CACHD1 and α2δ-1 mRNA in rat tissue determined using SYBR green real-time quantitative PCR and HPRT1 as the housekeeping gene. DRG, Dorsal root ganglion; SCG, superior cervical ganglion. (Data normalized to lowest tissue expression; n = 3 experiments using 3 animals each.) Figure 1 is supported by in situ hydridization data in different rat brain regions (Figure 1-1) and a qualitative expression profile of CACHD1 mRNA and protein in the adult rat brain (Figure 1-2).