Shi Qianqian, Chen Xin, Ma Lei, Wei Anzhi, Fei Xitong
College of Forestry, Northwest Agriculture and Forestry University, Xianyang, 712100, China.
Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration, Yangling, Xianyang, 712100, China.
Theor Appl Genet. 2025 Aug 3;138(8):195. doi: 10.1007/s00122-025-04985-x.
Apomixis is a form of asexual reproduction that produces offspring with the same genetic material as the female parent. Introducing apomixis into major food crops would revolutionize agricultural breeding by allowing the self-propagation of superior hybrids. We found that the MADS-box transcription factor D-class member AGAMOUS-like 11 (AGL11) plays a key role in the apomictic species Zanthoxylum bungeanum during somatic embryogenesis. Specific overexpression of the AGL11 gene in the nucellus induces somatic cells (nucellus cells) to differentiate into asexual embryos (adventitious embryos) and appear to be polyembryonic. FERTILIZATION-INDEPENDENT ENDOSPERM (FIE) acts as a switch to repress the development of the endosperm until fertilization, and knockdown of the FIE gene activates early cellularization of the central polar nucleus and produces a diploid endosperm independent of fertilization. AGL11-OE/fie-mutant maize was constructed by overexpressing AGL11 and knocking out the FIE gene in food crop maize, which produces asexual seeds by inducing somatic embryogenesis and autonomous endosperm. The AGL11-FIE module bypasses sexual reproduction and meiosis and induces asexual embryos and endosperm without fertilization, realizing the transformation of sexual reproduction into asexual reproduction. The results provided a reference for the self-production of hybrid seeds represented by maize.
无融合生殖是一种无性繁殖形式,能产生与母本具有相同遗传物质的后代。将无融合生殖引入主要粮食作物将彻底改变农业育种方式,使优良杂交种能够自我繁殖。我们发现,MADS盒转录因子D类成员AGAMOUS样11(AGL11)在无融合生殖物种花椒体细胞胚胎发生过程中起关键作用。在珠心组织中特异性过表达AGL11基因可诱导体细胞(珠心细胞)分化为无性胚(不定胚),且似乎会出现多胚现象。非受精胚乳(FIE)作为一种开关,在受精前抑制胚乳发育,敲低FIE基因可激活中央极核的早期细胞化,并产生不依赖受精的二倍体胚乳。通过在粮食作物玉米中过表达AGL11并敲除FIE基因,构建了AGL11-OE/fie突变体玉米,该突变体通过诱导体细胞胚胎发生和自主胚乳产生无性种子。AGL11-FIE模块绕过有性生殖和减数分裂,在未受精的情况下诱导无性胚和胚乳的形成,实现了有性生殖向无性生殖的转变。这些结果为以玉米为代表的杂交种子自我生产提供了参考。