OsSWEET14 cooperates with OsSWEET11 to contribute to grain filling in rice
OsSWEET14 cooperates with OsSWEET11 to contribute to grain filling in rice
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OsSWEET14 与 OsSWEET11 合作，为水稻籽粒灌浆做出贡献。
DOI：
10.1016/j.plantsci.2021.110851
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发表时间：
2021-02-23
期刊：
影响因子：
5.2
通讯作者：
Lu, Congming
中科院分区：
文献类型：
--
作者：
Fei, Honghong;Yang, Zhipan;Lu, Congming
谷粒灌浆过程对谷类作物的产量至关重要，但这类植物的颖果是如何提供糖分的，这些糖分是通过叶片的光合作用产生的，然后被远距离输送，这在很大程度上是未知的。在水稻（Oryza sativa）中，各种SWEET家族蔗糖转运蛋白被认为在籽粒灌浆中起重要作用。在这里，我们报道OsSWEET14在水稻的这一过程中起着至关重要的作用。Ossweet14基因敲除突变体与野生型没有任何可检测到的表型差异，而Ossweet14；与Ossweet11单敲除突变体相比，Ossweet11双敲除突变体的表型更为严重，包括籽粒重和产量严重下降，籽粒灌浆速率降低，果皮淀粉积累增加。OsSWEET14和OsSWEET11在颖果发育早期和快速灌浆期表现出不同的时空表达模式。在快速灌浆阶段，OsSWEET14和OsSWEET11定位于四个关键部位：维管薄壁细胞、珠心突起、珠心表皮和交叉细胞。上述结果表明，OsSWEET14在籽粒灌浆过程中发挥了重要作用，并提示在籽粒灌浆过程中，有4个主要的外质途径通过蔗糖外排物SWEET14和SWEET11向胚乳提供蔗糖。
The grain-filling process is crucial for cereal crop yields, but how the caryopsis of such plants is supplied with sugars, which are produced by photosynthesis in leaves and then transported long distance, is largely unknown. In rice (Oryza sativa), various SWEET family sucrose transporters are thought to have important roles in grain filling. Here, we report that OsSWEET14 plays a crucial part in this process in rice. ossweet14 knockout mutants did not show any detectable phenotypic differences from the wild type, whereas ossweet14;ossweet11 doubleknockout mutants had much more severe phenotypes than ossweet11 single-knockout mutants, including strongly reduced grain weight and yield, reduced grain-filling rate, and increased starch accumulation in the pericarp. Both OsSWEET14 and OsSWEET11 exhibited distinct spatiotemporal expression patterns between the early stage of caryopsis development and the rapid grain-filling stage. During the rapid grain-filling stage, OsSWEET14 and OsSWEET11 localized to four key sites: vascular parenchyma cells, the nucellar projection, the nucellar epidermis, and cross cells. These results demonstrate that OsSWEET14 plays an important role in grain filling, and they suggest that four major apoplasmic pathways supply sucrose to the endosperm during the rapid grain-filling stage via the sucrose effluxers SWEET14 and SWEET11.