Altered interactions between cis -regulatory elements partially resolve BLADE-ON-PETIOLE genetic redundancy in Capsella rubella

作者：Thi Chi Tran, Karoline Mähl, Christian Kappel, Yuri Dakhiya, Arun Sampathkumar, Adrien Sicard, Michael Lenhard · 发表于：The Plant Cell · 年份：2024 · DOI：10.1093/plcell/koae232 · 被引用次数：10 · 研究领域：Plant Molecular Biology Research、Viral Infectious Diseases and Gene Expression in Insects

Duplicated genes are thought to follow one of three evolutionary trajectories that resolve their redundancy: neofunctionalization, subfunctionalization, or pseudogenization. Differences in expression patterns have been documented for many duplicated gene pairs and interpreted as evidence of subfunctionalization and a loss of redundancy. However, little is known about the functional impact of such differences and about their molecular basis. Here, we investigate the genetic and molecular basis for the partial loss of redundancy between the two BLADE-ON-PETIOLE genes BOP1 and BOP2 in red shepherd's purse (Capsella rubella) compared to Arabidopsis (Arabidopsis thaliana). While both genes remain almost fully redundant in A. thaliana, BOP1 in C. rubella can no longer ensure wild-type floral organ numbers and suppress bract formation, due to an altered expression pattern in the region of the cryptic bract primordium. We use two complementary approaches, transgenic rescue of A. thaliana atbop1 atbop2 double mutants and deletions in the endogenous AtBOP1 promoter, to demonstrate that several BOP1 promoter regions containing conserved noncoding sequences interact in a nonadditive manner to control BOP1 expression in the bract primordium and that changes in these interactions underlie the evolutionary divergence between C. rubella and A. thaliana BOP1 expression and activity. Similarly, altered interactions between cis-regulatory regions underlie the divergence in functional promoter a...