Taxon-specific, phased siRNAs underlie a speciation locus in monkeyflowers

作者：Mei Liang, Wenjie Chen, Amy M. LaFountain, Yuanlong Liu, Foen Peng, Rui Xia, H. D. Bradshaw, Yao‐Wu Yuan · 发表于：Science · 年份：2023 · DOI：10.1126/science.adf1323 · 被引用次数：110 · 研究领域：Genomics and Phylogenetic Studies、Photosynthetic Processes and Mechanisms、Plant Reproductive Biology

Taxon-specific small RNA loci are widespread in eukaryotic genomes, yet their role in lineage-specific adaptation, phenotypic diversification, and speciation is poorly understood. Here, we report that a speciation locus in monkeyflowers ( Mimulus ), YELLOW UPPER ( YUP ), contains an inverted repeat region that produces small interfering RNAs (siRNAs) in a phased pattern. Although the inverted repeat is derived from a partial duplication of a protein-coding gene that is not involved in flower pigmentation, one of the siRNAs targets and represses a master regulator of floral carotenoid pigmentation. YUP emerged with two protein-coding genes that control other aspects of flower coloration as a “superlocus” in a subclade of Mimulus and has contributed to subsequent phenotypic diversification and pollinator-mediated speciation in the descendant species.