期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2016
卷号：113
期号：52
页码：15042-15047
DOI：10.1073/pnas.1615688114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceNutritional conditions during early development influence the plastic expression of adult phenotypes. Because heightened nutrition sensitivity often characterizes the development of exaggerated traits, there should be molecular mechanisms underlying trait-specific variability. This study reveals the molecular mechanisms underlying the expression of nutrition-sensitive mandibles in the beetle Gnatocerus cornutus. We found that epigenetic regulators, such as histone deacetylases (HDACs) and polycomb group (PcG) proteins, contribute specifically to the plastic expression of male mandibles, with little contribution to other body modules. In addition, HDAC1 and HDAC3 perturbation resulted in opposite phenotypic effects on mandible and wing modules. Our findings provide molecular evidence of a link between distinct epigenetic modifications and module-specific phenotypic plasticity of exaggerated traits. Nutritional conditions during early development influence the plastic expression of adult phenotypes. Among several body modules of animals, the development of sexually selected exaggerated traits exhibits striking nutrition sensitivity, resulting in positive allometry and hypervariability distinct from other traits. Using de novo RNA sequencing and comprehensive RNA interference (RNAi) for epigenetic modifying factors, we found that histone deacetylases (HDACs) and polycomb group (PcG) proteins preferentially influence the size of mandibles (exaggerated male weapon) and demonstrate nutrition-dependent hypervariability in the broad-horned flour beetle, Gnatocerus cornutus. RNAi-mediated HDAC1 knockdown (KD) in G. cornutus larvae caused specific curtailment of mandibles in adults, whereas HDAC3 KD led to hypertrophy. Notably, these KDs conferred opposite effects on wing size, but little effect on the size of the core body and genital modules. PcG RNAi also reduced adult mandible size. These results suggest that the plastic development of exaggerated traits is controlled in a module-specific manner by HDACs.
关键词：phenotypic plasticity ; HDAC ; Gnatocerus cornutus ; exaggerated male weapon ; sexual dimorphism
