Huang Tangwei, Luo Xinglu, Fan Zhupeng, Yang Yanni, Wan Wen
College of Agriculture, Guangxi University, Nanning 530004, China.
College of Agriculture, Guangxi University, Nanning 530004, China; State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Nanning 530004, China.
Gene. 2021 Feb 15;769:145191. doi: 10.1016/j.gene.2020.145191. Epub 2020 Sep 30.
Sucrose synthase (SUS), a key enzyme of the sucrose metabolism pathway, is encoded by a multi-gene family in plants. To date, dozens of SUS gene families have been characterized in various plant genomes. However, only a few studies have performed comprehensive analyses in tropical crops like cassava (Manihot esculenta Crantz). In the present study, seven non-redundant members of the SUS gene family (MeSUS1-7) were identified and characterized from the cassava genome. The MeSUS genes were distributed on five chromosomes (Chr1, Chr2, Chr3, Chr14, and Chr16) and the encoded proteins could be classified into three major groups with other SUS proteins from both dicot and monocot species (SUS I, SUS II, and SUS III). The spatio-temporal expression profiles of MeSUS genes showed a developmental stage-dependent, partially overlapping pattern, mainly expressed in the source and sink tissues. Cold and drought treatments significantly induced the expressions of MeSUS2, MeSUS4, MeSUS6, and MeSUS7 and the activities of the encoded enzymes, indicating that these genes may play crucial roles in resistance against abiotic stresses. These results provide new insights into the multifaceted role of the SUS gene family members in various physiological processes, especially sucrose transport and starch accumulation in cassava roots.
蔗糖合酶（SUS）是蔗糖代谢途径中的关键酶，由植物中的一个多基因家族编码。迄今为止，在各种植物基因组中已鉴定出数十个SUS基因家族。然而，只有少数研究对木薯（Manihot esculenta Crantz）等热带作物进行了全面分析。在本研究中，从木薯基因组中鉴定并表征了SUS基因家族的七个非冗余成员（MeSUS1-7）。MeSUS基因分布在五条染色体（Chr1、Chr2、Chr3、Chr14和Chr16）上，编码的蛋白质可与双子叶和单子叶物种的其他SUS蛋白质一起分为三大类（SUS I、SUS II和SUS III）。MeSUS基因的时空表达谱呈现出发育阶段依赖性、部分重叠的模式，主要在源组织和库组织中表达。冷胁迫和干旱胁迫显著诱导了MeSUS2、MeSUS4、MeSUS6和MeSUS7的表达以及编码酶的活性，表明这些基因可能在抗非生物胁迫中发挥关键作用。这些结果为SUS基因家族成员在各种生理过程中的多方面作用提供了新的见解，特别是在木薯根中的蔗糖运输和淀粉积累方面。
