This is a hypothetical model of what abscisic acid (ABA) looks like when bound to the receptor protein, PYR1. The yellow molecule is ABA and it is bound inside a pocket of PYR1.

Credit: Courtesy of Fawzi Razem" /> Credit: Courtesy of Fawzi Razem The paper: F.A. Razem et al., "The RNA-binding protein FCA is an abscisic acid receptor," Nature, 439:290-4, 2006. (Cited in 82 ...