文献类型： 外文期刊

作者： Shen, Si ¹ ; Ma, Si ² ; Chen, Xian-Min ¹ ; Yi, Fei ¹ ; Li, Bin-Bin ¹ ; Liang, Xiao-Gui ¹ ; Liao, Sheng-Jin ⁴ ; Gao, Li-Hong ² ; Zhou, Shun-Li ¹ ; Ruan, Yong-Ling ⁵ ;

作者机构： 1.China Agr Univ, Coll Agron & Biotechnol, Beijing 100193, Peoples R China

2.China Agr Univ, Coll Hort, Beijing Key Lab Growth & Dev Regulat Protected Ve, Beijing 100193, Peoples R China

3.Jiangxi Agr Univ, Res Ctr Ecol Sci, Nanchang, Jiangxi, Peoples R China

4.Beijing Acad Agr & Forestry Sci, Res Ctr Agr Informat & Technol, Beijing 100193, Peoples R China

5.Univ Newcastle, Sch Environm & Life Sci, Callaghan, NSW 2308, Australia

关键词： drought; grain development; maize; post-phloem transport; sucrose; sugar transporter

期刊名称：PLANT JOURNAL （ 影响因子：7.091； 五年影响因子：8.028 ）

ISSN： 0960-7412

年卷期： 2022 年 110 卷 1 期

页码：

收录情况： SCI

摘要： Developing seed depends on sugar supply for its growth and yield formation. Maize (Zea mays L.) produces the largest grains among cereals. However, there is a lack of holistic understanding of the transcriptional landscape of genes controlling sucrose transport to, and utilization within, maize grains. By performing in-depth data mining of spatio-temporal transcriptomes coupled with histological and heterologous functional analyses, we identified transporter genes specifically expressed in the maternal-filial interface, including (i) ZmSWEET11/13b in the placento-chalazal zone, where sucrose is exported into the apoplasmic space, and (ii) ZmSTP3, ZmSWEET3a/4c (monosaccharide transporters), ZmSUT1, and ZmSWEET11/13a (sucrose transporters) in the basal endosperm transfer cells for retrieval of apoplasmic sucrose or hexoses after hydrolysis by extracellular invertase. In the embryo and its surrounding regions, an embryo-localized ZmSUT4 and a cohort of ZmSWEETs were specifically expressed. Interestingly, drought repressed those ZmSWEETs likely exporting sucrose but enhanced the expression of most transporter genes for uptake of apoplasmic sugars. Importantly, this drought-induced fluctuation in gene expression was largely attenuated by an increased C supply via controlled pollination, indicating that the altered gene expression is conditioned by C availability. Based on the analyses above, we proposed a holistic model on the spatio-temporal expression of genes that likely govern sugar transport and utilization across maize maternal and endosperm and embryo tissues during the critical stage of grain set. Collectively, the findings represent an advancement towards a holistic understanding of the transcriptional landscape underlying post-phloem sugar transport in maize grain and indicate that the drought-induced changes in gene expression are attributable to low C status.