Biomass Accumulation and Cell Wall Structure of Rice Plants Overexpressing a Dirigent-Jacalin of Sugarcane (ShDJ) Under Varying Conditions of Water Availability
Biomass Accumulation and Cell Wall Structure of Rice Plants Overexpressing a Dirigent-Jacalin of Sugarcane (ShDJ) Under Varying Conditions of Water Availability
复制标题
DOI：
10.3389/fpls.2019.00065
复制
发表时间：
2019-02-13
影响因子：
5.6
通讯作者：
Creste, Silvana
中科院分区：
文献类型：
--
作者：
Andrade, Larissa Mara;Peixoto-Junior, Rafael Favero;Creste, Silvana
在干旱胁迫下诱导了一个甘蔗基因ShDJ，该基因编码一种介导剂-菠萝卜素。为了阐明其生物学功能，我们通过农杆菌介导法将ShDJ过表达构建到水稻日本晴基因组中。在T-1和T-4两个世代中选择了两个T-0单拷贝基因的转基因品系并进行了鉴定。转基因株系在缺水条件下显著提高了存活率，存活率接近100%，而WT则没有存活。此外，与WT植株相比，转基因植株在水分亏缺条件下具有更高的生物量和更高的分蘖能力。在水分充足和水分亏缺条件下，转基因株系的果胶和半纤维素含量均低于野生型植株，而纤维素含量在水分利用率低的情况下，17号品系没有变化，29号品系则有所降低。水分亏缺条件下木质素含量的变化仅见于品系#17，但两个转基因品系的糖化作用都有所改善，同时细胞壁次生合成基因OsNTS1/2和OsMYB58/63的表达也发生了变化。在水分充足的条件下，ShDJ过表达上调水稻茎中OsbZIP23、OsGRAS23、OsP5CS和OsLea3基因的表达。综上所述，我们的数据表明ShDJ具有提高抗旱性、植物生物量积累和糖化效率的潜力。
A sugarcane gene encoding a dirigent-jacalin, ShDJ, was induced under drought stress. To elucidate its biological function, we integrated a ShDJ-overexpression construction into the rice Nipponbare genome via Agrobacterium- mediated transformation. Two transgenic lines with a single copy gene in T-0 were selected and evaluated in both the T-1 and T-4 generations. Transgenic lines had drastically improved survival rate under water deficit conditions, at rates close to 100%, while WT did not survive. Besides, transgenic lines had improved biomass production and higher tillering under water deficit conditions compared with WT plants. Reduced pectin and hemicellulose contents were observed in transgenic lines compared with wild-type plants under both well-watered and water deficit conditions, whereas cellulose content was unchanged in line #17 and reduced in line #29 under conditions of low water availability. Changes in lignin content under water deficit were only observed in line #17. However, improvements in saccharification were found in both transgenic lines along with changes in the expression of OsNTS1/2 and OsMYB58/63 secondary cell wall biosynthesis genes. ShDJ-overexpression upregulated the expression of the OsbZIP23, OsGRAS23, OsP5CS, and OsLea3 genes in rice stems under well-watered conditions. Taken together, our data suggest that ShDJ has the potential for improving drought tolerance, plant biomass accumulation, and saccharification efficiency.