Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany.
Deep Sequencing Core Facility, CellNetworks Excellence Cluster, Heidelberg University, Im Neuenheimer Feld 267, D-69120, Heidelberg, Germany.
Development. 2021 Oct 1;148(19). doi: 10.1242/dev.198739. Epub 2021 Oct 8.
Plant sexual and asexual reproduction through seeds (apomixis) is tightly controlled by complex gene regulatory programs, which are not yet fully understood. Recent findings suggest that RNA helicases are required for plant germline development. This resembles their crucial roles in animals, where they are involved in controlling gene activity and the maintenance of genome integrity. Here, we identified previously unknown roles of Arabidopsis RH17 during reproductive development. Interestingly, RH17 is involved in repression of reproductive fate and of elements of seed development in the absence of fertilization. In lines carrying a mutant rh17 allele, development of supernumerary reproductive cell lineages in the female flower tissues (ovules) was observed, occasionally leading to formation of two embryos per seed. Furthermore, seed coat, and putatively also endosperm development, frequently initiated autonomously. Such induction of several features phenocopying distinct elements of apomixis by a single mutation is unusual and suggests that RH17 acts in regulatory control of plant reproductive development. Furthermore, an in-depth understanding of its action might be of use for agricultural applications.
植物有性和无性生殖通过种子（无融合生殖）来实现，这一过程受到复杂的基因调控程序的严格控制，但目前还不完全清楚。最近的研究结果表明，RNA 解旋酶对于植物生殖细胞的发育是必需的。这与它们在动物中的关键作用类似，在动物中，它们参与控制基因活性和基因组完整性的维持。在这里，我们鉴定了拟南芥 RH17 在生殖发育过程中的以前未知的作用。有趣的是，RH17 参与抑制生殖命运和在没有受精的情况下种子发育的元件。在携带突变 rh17 等位基因的系中，在雌性花组织（胚珠）中观察到多余的生殖细胞谱系的发育，偶尔导致每个种子形成两个胚胎。此外，种皮，以及可能的胚乳发育，经常自主启动。这种由单个突变引起的对无融合生殖的多个特征的诱导是不寻常的，这表明 RH17 作用于植物生殖发育的调控控制。此外，对其作用的深入了解可能对农业应用有用。
