Department of Plant and Soil Science, 219 Experimental Sciences Building, Texas Tech University, Lubbock, TX, 79409, USA.
Plant Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka, 411-8540, Japan.
Sci Rep. 2018 Nov 5;8(1):16346. doi: 10.1038/s41598-018-34608-z.
Oryza officinalis is an accessible alien donor for genetic improvement of rice. Comparison across a representative panel of Oryza species showed that the wild O. officinalis and cultivated O. sativa ssp. japonica have similar cold tolerance potentials. The possibility that either distinct or similar genetic mechanisms are involved in the low temperature responses of each species was addressed by comparing their transcriptional networks. General similarities were supported by shared transcriptomic signatures indicative of equivalent metabolic, hormonal, and defense status. However, O. officinalis has maintained an elaborate cold-responsive brassinosteroid-regulated BES1-network that appeared to have been fragmented in O. sativa. BES1-network is potentially important for integrating growth-related responses with physiological adjustments and defenses through the protection of photosynthetic machinery and maintenance of stomatal aperture, oxidative defenses, and osmotic adjustment. Equivalent physiological processes are functional in O. sativa but their genetic mechanisms are under the direct control of ABA-dependent, DREB-dependent and/or oxidative-mediated networks uncoupled to BES1. While O. officinalis and O. sativa represent long periods of speciation and domestication, their comparable cold tolerance potentials involve equivalent physiological processes but distinct genetic networks. BES1-network represents a novel attribute of O. officinalis with potential applications in diversifying or complementing other mechanisms in the cultivated germplasm.
药用野生稻是改良水稻遗传的一种易得的外来供体。对代表性的稻种进行比较，野生稻种和栽培稻种粳亚种的耐寒潜力相似。通过比较它们的转录网络，研究了每个物种低温响应中涉及的遗传机制是不同还是相似。共有转录组特征表明，每个物种的代谢、激素和防御状态相当，这支持了一般的相似性。然而，药用野生稻保留了一个复杂的低温响应的油菜素内酯调控的 BES1 网络，而这个网络在栽培稻中似乎已经碎片化了。BES1 网络可能通过保护光合作用机器和维持气孔开度、氧化防御和渗透调节，将生长相关反应与生理调节和防御整合在一起。在栽培稻中也存在着等效的生理过程，但它们的遗传机制受 ABA 依赖、DREB 依赖和/或与 BES1 不相关的氧化介导网络的直接控制。虽然药用野生稻和栽培稻代表了很长的物种形成和驯化时期，但它们相当的耐寒潜力涉及等效的生理过程和不同的遗传网络。BES1 网络是药用野生稻的一个新特征，可能在多样化或补充栽培种质的其他机制方面具有应用潜力。
