Key message

CHR721 functions as a chromatin remodeler and interacts with a known single-stranded binding protein, OsRPA1a, to regulate both male and female reproductive development in rice.

Abstract

Reproductive development and fertility are important for seed production in rice. Here, we identified a sterile rice mutant, chr721, that exhibited defects in both male and female reproductive development. Approximately 5% of the observed defects in chr721, such as asynchronous dyad division, occurred during anaphase II of meiosis. During the mitotic stage, approximately 80% of uninucleate microspores failed to develop into tricellular pollen, leading to abnormal development. In addition, defects in megaspore development were detected after functional megaspore formation. CHR721, which encodes a nuclear protein belonging to the SNF2 subfamily SMARCAL1, was identified by map-based cloning. CHR721 was expressed in various tissues, especially in spikelets. CHR721 was found to interact with replication protein A (OsRPA1a), which is involved in DNA repair. The expressions of genes involved in DNA repair and cell-cycle checkpoints were consistently upregulated in chr721. Although numerous genes involved in male and female development have been identified, the mode of participation of chromatin-remodeling factors in reproductive development is still not well understood. Our results suggest that CHR721, a novel gene cloned from rice, plays a vital role in both male and female reproductive development.

中文翻译：

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CHR721 与 OsRPA1a 相互作用，对水稻雄性和雌性生殖发育至关重要。

关键信息

CHR721作为染色质重塑剂发挥作用，并与已知的单链结合蛋白 OsRPA1a 相互作用，从而调节水稻的雄性和雌性生殖发育。

抽象的

生殖发育和肥力对水稻种子生产很重要。在这里，我们鉴定了一种不育水稻突变体chr721，它在雄性和雌性生殖发育中都表现出缺陷。在chr721中观察到的大约 5% 的缺陷（例如异步二元分裂）发生在减数分裂后期 II 期间。在有丝分裂阶段，约80%的单核小孢子未能发育成三细胞花粉，导致发育异常。此外，在功能性大孢子形成后检测到大孢子发育缺陷。通过基于图谱的克隆鉴定了编码属于 SNF2 亚家族SMARCAL1的核蛋白的 CHR721。CHR721在各种组织中表达，特别是在小穗中。发现 CHR721 与参与 DNA 修复的复制蛋白 A (OsRPA1a) 相互作用。在chr721中，参与 DNA 修复和细胞周期检查点的基因表达持续上调。尽管已经确定了许多参与男性和女性发育的基因，但染色质重塑因子参与生殖发育的模式仍不清楚。我们的研究结果表明，从水稻中克隆的新基因CHR721在雄性和雌性生殖发育中都起着至关重要的作用。