Teosinte Pollen Drive guides maize domestication and evolution by RNA interference [WGS]

Meiotic drivers subvert Mendelian expectations by manipulating reproductive development to bias their own transmission. Chromosomal drive typically functions in asymmetric female meiosis, while gene drive is normally postmeiotic and typically found in males. Cryptic drive is thought to be pervasive and can be unleashed following hybridization with a naïve genome, resulting in sterility and hybrid incompatibility. Using single molecule and single pollen genome sequencing, we describe an instance of gene drive in hybrids between maize (Zea mays ssp. mays) and teosinte mexicana (Zea mays ssp. mexicana), that depends on RNA interference (RNAi) in the male germline. Multiple hairpin-derived small RNA from mexicana target a novel domestication gene, Teosinte Drive Responder, that is required for pollen fertility and has undergone selection for immunity to RNAi. Introgression of mexicana into early cultivated maize is thought to have been critical to its geographical dispersal throughout the Americas. A survey of maize landraces and sympatric populations of teosinte mexicana reveals allelic bias at genes required for RNAi on at least 4 chromosomes that are also subject to gene drive in pollen from synthetic hybrids. Teosinte Pollen Drive likely played a major role in maize domestication, and offers an explanation for the widespread abundance of hairpin-encoded and other endogenous small RNA in the germlines of plants and animals. WGS of separately maintained Tpd1;Tpd2 lineages (BC8S3, BC5S2) and bulk segregation analysis (BSA) maternal pools

减数分裂驱动因子（Meiotic drivers）通过调控生殖发育过程以偏向自身的传递效率，从而颠覆孟德尔遗传预期。染色体驱动通常在不对称的雌性减数分裂中发挥功能，而基因驱动（gene drive）通常发生于减数分裂后阶段，且多存在于雄性个体中。隐蔽驱动（Cryptic drive）被认为广泛存在，当其与未致敏基因组（naïve genome）杂交后便可被激活，进而引发不育与杂交不亲和。本研究利用单分子测序与单花粉基因组测序技术，报道了玉米（Zea mays ssp. mays）与墨西哥类玉米（Zea mays ssp. mexicana）杂交后代中存在的一例基因驱动现象，该现象依赖于雄性生殖系中的RNA干扰（RNA interference, RNAi）通路。多个源自墨西哥类玉米的发夹结构衍生小RNA靶向一个全新的驯化基因——类玉米驱动响应因子（Teosinte Drive Responder），该基因对花粉育性至关重要，且已演化出针对RNA干扰的免疫抗性。学界普遍认为，墨西哥类玉米向早期栽培玉米的基因渐渗（introgression）对玉米在美洲大陆的地理扩散起到了关键作用。对玉米地方品种与同域分布的墨西哥类玉米种群的调查显示，至少4条染色体上的RNAi相关基因存在等位基因偏向性，这些基因在人工创制的杂交种花粉中同样受到基因驱动的调控。类玉米花粉驱动很可能在玉米驯化过程中发挥了核心作用，同时也为动植物生殖系中广泛存在的发夹编码及其他内源性小RNA的高丰度现象提供了合理解释。本研究对分别保种的Tpd1;Tpd2谱系（BC8S3、BC5S2）以及混合分离分析（bulk segregation analysis, BSA）的母本混池开展了全基因组测序（WGS）