Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing, 400030, China.
Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing, 400030, China.
Plant Physiol Biochem. 2018 Sep;130:566-576. doi: 10.1016/j.plaphy.2018.08.008. Epub 2018 Aug 8.
Root system architecture represents an underexplored target for improving global crop yields. In this study, we investigated the biological role of the rice root-specific gene RCc3 in improving root growth and responses to abiotic stress by overexpressing RCc3 in rice plants. RCc3 was induced by osmotic and heat stress. RCc3 overexpression produced pleiotropic phenotypes of improved root system architecture, including increased growth of primary root, adventitious roots and lateral roots at the seedling stage. Further study indicated that auxin accumulation in the root was increased through auxin local biosynthesis and polar auxin transport in RCc3 overexpression lines. At maturity, the plant height and panicle traits were also significantly enhanced in overexpression plants. Under osmotic and heat stress conditions, the root and shoot growth were less severely inhibited in RCc3 overexpressing transgenic plants than that in wild-type plants, and the transcript levels of abiotic stress-related genes were significantly increased. Moreover, overexpression of RCc3 remarkably enhanced the tolerance to salt stress, with the elevated activities of antioxidant enzymes. Taken together, the data showed that RCc3 overexpression can improve rice root system, promote plant growth, and enhance plant tolerance to salt stress.
根系结构代表了一个尚未充分探索的目标，可以用来提高全球作物产量。在这项研究中，我们通过在水稻植株中过表达 RCc3 来研究水稻根特异性基因 RCc3 对改善根生长和应对非生物胁迫的生物学作用。RCc3 受到渗透和热胁迫的诱导。RCc3 的过表达产生了根系结构改良的多种表型，包括幼苗期主根、不定根和侧根生长的增加。进一步的研究表明，RCc3 过表达系中通过生长素局部生物合成和极性生长素运输增加了生长素在根中的积累。在成熟时，过表达植株的株高和穗部特征也显著增强。在渗透和热胁迫条件下，RCc3 过表达转基因植物的根和地上部生长受抑制程度低于野生型植物，非生物胁迫相关基因的转录水平显著增加。此外，RCc3 的过表达显著增强了水稻对盐胁迫的耐受性，抗氧化酶的活性也显著提高。综上所述，数据表明 RCc3 的过表达可以改善水稻根系，促进植物生长，并增强植物对盐胁迫的耐受性。
