研究人员将两种不同的孟德尔遗传机制与古老（超过3700万年）的全属结构DNA多态性进行了映射。在胡桃属中，雌先开花的显性单倍型包含一个基因的3′非翻译区串联重复序列。该基因可能涉及海藻糖-6-磷酸代谢，并且与发育中的雄性花朵中顺式基因表达的增加相关，这可能是通过小RNA介导的。
山核桃的位点包含约20个同源基因，并显示出性别染色体类进化的分子特征。异时开花的遗传机制在演化中得到了深刻的保守，但也可能偶尔发生改变，就像性别决定一样。
据了解，平衡的配子型多态性为人们提供了一个独特的视角，帮助理解塑造性别繁殖策略的力量。胡桃科（Juglandaceae）中的多个雌雄同体属，包括胡桃属（Juglans）和山核桃属（Carya），展示了雄性与雌性开花顺序的1:1遗传二态性（异时开花）。
附：英文原文
Title: Ancient structural variants control sex-specific flowering time morphs in walnuts and hickories
Author: Jeffrey S. Groh, Diane C. Vik, Matthew Davis, J. Grey Monroe, Kristian A. Stevens, Patrick J. Brown, Charles H. Langley, Graham Coop
Issue&Volume: 2025-01-03
Abstract: Balanced mating type polymorphisms offer a distinct window into the forces shaping sexual reproduction strategies. Multiple hermaphroditic genera in Juglandaceae, including walnuts (Juglans) and hickories (Carya), show a 1:1 genetic dimorphism for male versus female flowering order (heterodichogamy). We map two distinct Mendelian inheritance mechanisms to ancient (>37 million years old) genus-wide structural DNA polymorphisms. The dominant haplotype for female-first flowering in Juglans contains tandem repeats of the 3′ untranslated region of a gene putatively involved in trehalose-6-phosphate metabolism and is associated with increased cis gene expression in developing male flowers, possibly mediated by small RNAs. The Carya locus contains ~20 syntenic genes and shows molecular signatures of sex chromosome–like evolution. Inheritance mechanisms for heterodichogamy are deeply conserved, yet may occasionally turn over, as in sex determination.
DOI: ado5578
Source: https://www.science.org/doi/10.1126/science.ado5578