Os4BGlu14, a monolignol β-Glucosidase, negatively affects seed longevity by influencing primary metabolism in rice
Os4BGlu14, a monolignol β-Glucosidase, negatively affects seed longevity by influencing primary metabolism in rice
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Os4BGlu14 是一种木质醇 β-葡萄糖苷酶，通过影响水稻的初级代谢对种子寿命产生负面影响
DOI：
10.1007/s11103-020-01056-1
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发表时间：
2020-08-24
影响因子：
5.1
通讯作者：
Chen, Xi-Wen
中科院分区：
文献类型：
--
作者：
Ren, Rui-Juan;Wang, Pei;Chen, Xi-Wen
Os4BGlu14是一种单脂醇β -葡萄糖苷酶，通过影响种子发育和衰老过程中的初级代谢而对种子寿命起负面作用。种子寿命是农业和种质资源保护中的一项重要性状。-葡萄糖苷酶（BGlus）是一种影响植物生长及其对环境适应的多功能酶。然而，水稻BGlus在种子寿命中的作用尚不清楚。我们在这里报道了水稻β -葡萄糖苷酶Os4BGlu14在加速老化过程中对种子寿命产生负面影响。Os4BGlu14在水稻胚中高表达，通过加速老化诱导。与野生型相比，过表达Os4BGlu14的水稻株系的粒长明显增大，但粒宽和粒厚明显减小。过表达（OE）系淀粉含量较低，葡萄糖含量较高。加速老化处理后，OE系的发芽率显著低于野生型。此外，这些品系在加速老化前后木质素积累量较高。代谢组学分析在未处理和老化的水稻种子中检测到217种代谢物。比较WT与OE5的代谢物差异发现，10种关键代谢物可能是导致种子变质的关键因素，其中4种代谢物（如尿苷5′-二磷酸葡萄糖-葡萄糖，UDPG）增加，6种代谢物（如γ -氨基丁酸和蛋氨酸）减少。进一步的分析证实，与野生型相比，OE系的UDPG水平更高，程序性细胞死亡更严重。此外，与野生型相比，OE系在萌发过程中经脱落酸和多效唑处理的发芽率较低。本研究为了解Os4BGlu14在水稻种子寿命中的作用提供了基础。
Key message Os4BGlu14, a monolignol beta-glucosidase, plays a negative role in seed longevity by affecting primary metabolism during seed development and aging. Seed longevity is a crucial trait in agriculture and in the conservation of germplasm resources.beta-Glucosidases (BGlus) are multifunctional enzymes that affect plant growth and their adaptation to the environment. The function of rice BGlus in seed longevity, however, remains unknown. We report here that Os4BGlu14, a rice beta-Glucosidase, negatively affected seed longevity during accelerated aging. Os4BGlu14 was highly expressed in rice embryos and induced by accelerated aging. Compared to the wild type, rice lines overexpressing Os4BGlu14 had significantly greater grain length, but smaller grain width and thickness. Overexpressing (OE) lines also showed lower starch but higher glucose contents. After accelerated aging treatment, OE lines displayed a significantly lower germination percentage than the wild type. Additionally, these lines had higher lignin accumulation before and after accelerated aging. Metabolome analysis detected 217 metabolites in untreated and aged rice seeds. Comparison of the differential metabolites between WT and OE5 revealed that ten key metabolites, four of which (e.g., uridine 5 '-diphosphoglucose-glucose, UDPG) were increased, while the other six (e.g.,gamma-aminobutyric acid and methionine) were decreased, might be the crucial factors that lead to seed deterioration. Further analysis confirmed higher UDPG levels and more severe programmed cell death in OE lines than in the wild type. Furthermore, OE lines presented a lower germination rate after abscisic acid and paclobutrazol treatment during germination, compared to the wild type. Our study provides a basis for understanding the function of Os4BGlu14 in seed longevity in rice.