Rice Transcription Factor OsDOF11 Modulates Sugar Transport by Promoting Expression of Sucrose Transporter and SWEET Genes
Rice Transcription Factor OsDOF11 Modulates Sugar Transport by Promoting Expression of Sucrose Transporter and SWEET Genes
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DOI：
10.1016/j.molp.2018.04.002
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发表时间：
2018-06-04
期刊：
影响因子：
27.5
通讯作者：
An, Gynheung
中科院分区：
文献类型：
--
作者：
Wu, Yunfei;Lee, Sang-Kyu;An, Gynheung
蔗糖在叶肉细胞中产生，并在长距离输送到库组织之前转移到韧皮部细胞中。然而，很少有人知道蔗糖运输是如何在植物中进行调节。在此，我们鉴定了水稻DNA结合单指11（OsDOF 11）的T-DNA插入突变体，该突变体在光合器官的维管细胞和各种库组织中表达。与野生型（WT）植物相比，osdof 11突变体植物是半矮秆的，并且具有较少的分蘖和较小的圆锥花序。虽然蔗糖增强根伸长在年轻的WT幼苗，这种增强没有发生在osdof 11幼苗由于减少蔗糖吸收。糖转运率分析表明，在osdof 11植物中转运的糖比在WT中少。OsSUT 1、OsSUT 3、OsSUT 4和OsSUT 5等4个蔗糖转运蛋白基因以及OsSWEET 11和OsSWEET 14等2个糖最终输出转运蛋白基因的表达在突变体的不同器官（包括叶片）中发生了改变。染色质免疫沉淀实验表明，OsDOF 11与SUT 1、OsSWEET 11和OsSWEET 14的启动子区直接结合，表明OsDOF 11协同控制这些转运蛋白的表达，这些转运蛋白通过质外体装载转运蔗糖。OsDOF 11突变体对黄单胞菌致病变种的侵染敏感性降低，表明OsDOF 11参与了病原菌侵染过程中的糖分配。总的来说，这些结果表明OsDOF 11通过调节SUT和SWEET基因在水稻中的表达来调节糖转运。
Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered longdistance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 (OsDOF11), which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdof11 mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type (WT) plants. Although sucrose enhanced root elongation in young WT seedlings, this enhancement did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdof11 plants than in the WT. Expression of four Sucrose Transporter (SUT) genes-OsSUT1, OsSUT3, OsSUT4, and OsSUT5-as well as two Sugars Will Eventually be Exported Transporters (SWEET) genes, OsSWEET11 and OsSWEET14, was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOF11 directly binds the promoter regions of SUT1, OsSWEET11, and OsSWEET14, indicating that the expression of these transporters responsible for sucrose transport via apoplastic loading is coordinately controlled by OsDOF11. Wealso observed that osdof11 mutant plants were less susceptible to infection by Xanthomonas oryzae pathovar oryzae, suggesting that OsDOF11 participates in sugar distribution during pathogenic invasion. Collectively, these results suggest that OsDOF11 modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice.