Overexpression of hexose transporter CsHT3 increases cellulose content in cucumber fruit peduncle
Overexpression of hexose transporter CsHT3 increases cellulose content in cucumber fruit peduncle
复制标题
己糖转运蛋白 CsHT3 的过表达增加了黄瓜果梗中的纤维素含量
DOI：
10.1016/j.plaphy.2019.10.034
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发表时间：
2019-12-01
影响因子：
6.5
通讯作者：
Bie, Zhilong
中科院分区：
文献类型：
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作者：
Cheng, Jintao;Wen, Suying;Bie, Zhilong
己糖转运蛋白在植物发育过程中起着重要的作用。然而，己糖转运蛋白在次生细胞壁生长中的作用还未见报道。在这里，我们报告，己糖转运蛋白基因CsHT3主要表达在细胞次生细胞壁在黄瓜。时空表达分析表明，CsHT 3的转录本主要积累在茎，叶柄，卷须，和花序梗，所有这些都含有高纤维素水平。免疫定位结果表明，CsHT 3是本地化的石细胞在年轻的花序梗，转移到韧皮部纤维细胞在花序梗的发展，然后再次转移到伴侣细胞时，次生细胞壁的发展几乎完成。碳荧光卸载实验表明，韧皮部碳水化合物的卸载遵循质外体途径。在黄瓜植株中过量表达CsHT 3可以提高花梗韧皮纤维细胞的纤维素含量和细胞壁厚度。在CsHT3过表达植株中纤维素合酶基因的表达增加。这些结果表明，CsHT 3可能通过促进纤维素合成酶基因的表达而在纤维素合成中发挥重要作用。
Hexose transporters play many important roles in plant development. However, the role of hexose transporter in secondary cell wall growth has not been reported before. Here, we report that the hexose transporter gene CsHT3 is mainly expressed in cells with secondary cell walls in cucumber. Spatiotemporal expression analysis revealed that the transcript of CsHT3 mainly accumulates in the stem, petiole, tendril, and peduncle, all of which contain high cellulose levels. Immunolocalization results show that CsHT3 is localized at the sclereids in young peduncles, shifts to the phloem fiber cells during peduncle development, and then shifts again to the companion cells when the development of secondary cell walls is almost completed. Carboxyfluoresce unloading experiment indicated that carbohydrate unloading in the phloem follows an apoplastic pathway. Overexpression of CsHT3 in cucumber plant can improve the cellulose content and cell wall thickness of phloem fiber cells in the peduncle. The expression of cellulose synthase genes were increased in the CsHT3 overexpression plants. These results indicated that CsHT3 may play an important role in cellulose synthesis through promoting the expression of cellulose synthase genes.