Much of the interest and excitement in the field of “Evo-Devo” today centers on the roles that changes in gene regulation may play in the evolution. This mechanism (altering when and/or where a particular gene is expressed during development) stands apart from that concerning changes in the actual structure and function of individual proteins. A recent study from Steve Tanksley’s lab brings this phenomenon into focus for this blog, and may tie together some different themes.
This study (Cong et al., Regulatory change in YABBY-like transcription factor led to evolution of extreme fruit size during tomato domestication, Nature Genetics 40, 800-804, 2008 ) deals with one of the two processes (cell cycle control and organ number determination) associated with the enlargement of tomato fruit size in the course of domestication of this crop. Many years of QTL mapping have led researchers to regions of the tomato genome involved in these processes. The study by Cong et al. describes the end result of the characterization of one of these QTLs, a locus that is a major contributor to organ number (specifically, carpel number).