 This study provides researchers with an easily accessible mRNA profile of the endogenous signaling repertoire of four commonly used cell lines for GPCR research, HEK293, ATT20, BV2, and N18. This will allow researchers to choose the most appropriate cell line for their experiments, as well as provide insight into potential interactions between GPCRs and other signaling proteins. This article was authored by Mackie Ken, Wajamilla James, Lopez Jacqueline, and others.