iHuman cloning core was set up in 2013. The goal of cloning core is to build a high efficient and high-throughput platform for optimized human GPCR gene cloning, expression construct design and optimization for in vitro scale-up of expression and purification. GPCRknown as difficult targets to express in heterogeneous system. Thus, molecular cloning is one of the key step for GPCR structural and functional studies. We have adopted new techniques to ensure excellent molecular biology support to iHuman researchers.