Novel human G protein-coupled receptors with long N-terminals containing GPS domains and Ser/Thr-rich regions

We report eight novel members of the superfamily of human G protein-coupled receptors (GPCRs) found by searches in the human genome databases, termed GPR97, GPR110, GPR111, GPR112, GPR113, GPR114, GPR115 and GPR116. Phylogenetic analysis shows that these are additional members of a family of GPCRs with long N-termini, previously termed EGF-7TM, LNB-7TM, B2 or LN-7TM. Five of the receptors form their own phylogenetic cluster, while three others form a cluster with the previously reported HE6 and GPR56 (TM7XN1). All the receptors have a GPS domain in their N-terminus and long Ser/Thr-rich regions forming mucin-like stalks. GPR113 has a hormone binding domain and one EGF domain. GPR112 has over 20 Ser/Thr repeats and a pentraxin domain. GPR116 has two immunoglobulin-like repeats and a SEA box. We found several human EST sequences for most of the receptors showing differential expression patterns, which may indicate that some of these receptors participate in reproductive functions while others are more likely to have a role in the immune system.