In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.

Yohimbine dimers exhibiting selectivity for the human alpha 2C-adrenoceptor subtype.
human alpha 2C-adrenoceptor

Two pharmacologically distinct alpha 1-adrenoceptor subtypes in the contraction of rabbit aorta: each subtype couples with a different Ca2+ signalling mechanism and plays a different physiological role.
alpha 1-adrenoceptor

A fluorescence resonance energy transfer-based M2 muscarinic receptor sensor reveals rapid kinetics of allosteric modulation.

M2 muscarinic receptor