An early ABA-induced stomatal closure, Na+ sequestration in leaf vein and K+ retention in mesophyll confer salt tissue tolerance in Cucurbita species.
An early ABA-induced stomatal closure, Na+ sequestration in leaf vein and K+ retention in mesophyll confer salt tissue tolerance in Cucurbita species.
复制标题
ABA 诱导的早期气孔关闭、叶脉中的钠封存和叶肉中的钾保留赋予了葫芦属的盐组织耐受性
DOI：
10.1093/jxb/ery251
复制
发表时间：
2018-09-14
影响因子：
6.9
通讯作者：
Bie Z
中科院分区：
文献类型：
--
作者：
Niu M;Xie J;Chen C;Cao H;Sun J;Kong Q;Shabala S;Shabala L;Huang Y;Bie Z
葫芦属植物的组织耐盐性与HKT 1介导的叶肉Na+排斥、NHX 4/6介导的叶脉Na+螯合、叶肉K+滞留和ABA诱导的气孔早期关闭有关。组织耐盐性是一个复杂的生理性状，包括多个“亚性状”，如Na+区室化，K+潴留，渗透胁迫的耐受性。以前的研究表明，一些南瓜属物种利用组织耐受性来对抗盐度，我们的目的是确定所涉及的生理和分子机制。五C maxima（耐盐）和5个C.对moschata（盐敏感）基因型的耐盐机制进行了综合评价，结果表明，组织特异性运输特性使更耐盐的品系能够应对盐负荷。这一机制与耐盐植物在叶片中积累更多的Na+和在叶肉中保留更多的K+的能力有关。此外，C.在短暂的NaCl胁迫下，maxima能更有效地将K+保留在根中，也能将更多的Na+储存在叶脉的木质部薄壁组织和皮层中。与C. moschata，C. maxima在盐胁迫初期也能迅速关闭气孔，避免水分流失，这是由于叶片中阿坝积累量较高所致。转录组和qRT-PCR分析揭示了高亲和力钾（HKT 1）和细胞内Na+/H+（NHX 4/6）转运蛋白作为使Na+从叶肉中排除和Na+在叶脉中隔离的机制的组分的关键作用。NCED 3s（编码9-顺式-环氧类胡萝卜素双加氧酶，阿坝生物合成的关键限速酶）的高表达也是必需的，这导致C.马克西姆
Tissue tolerance to salinity in Cucurbita is associated with HKT1-mediated Na+ exclusion from the leaf mesophyll, NHX4/6-mediated Na+ sequestration in the leaf vein, K+ retention in the leaf mesophyll, and early ABA-induced stomatal closure. Tissue tolerance to salinity stress is a complex physiological trait composed of multiple ‘sub-traits’ such as Na+ compartmentalization, K+ retention, and osmotic tolerance. Previous studies have shown that some Cucurbita species employ tissue tolerance to combat salinity and we aimed to identify the physiological and molecular mechanisms involved. Five C. maxima (salt-tolerant) and five C. moschata (salt-sensitive) genotypes were comprehensively assessed for their salt tolerance mechanisms and the results showed that tissue-specific transport characteristics enabled the more tolerant lines to deal with the salt load. This mechanism was associated with the ability of the tolerant species to accumulate more Na+ in the leaf vein and to retain more K+ in the leaf mesophyll. In addition, C. maxima more efficiently retained K+ in the roots when exposed to transient NaCl stress and it was also able to store more Na+ in the xylem parenchyma and cortex in the leaf vein. Compared with C. moschata, C. maxima was also able to rapidly close stomata at early stages of salt stress, thus avoiding water loss; this difference was attributed to higher accumulation of ABA in the leaf. Transcriptome and qRT-PCR analyses revealed critical roles of high-affinity potassium (HKT1) and intracellular Na+/H+ (NHX4/6) transporters as components of the mechanism enabling Na+ exclusion from the leaf mesophyll and Na+ sequestration in the leaf vein. Also essential was a higher expression of NCED3s (encoding 9-cis–epoxycarotenoid dioxygenase, a key rate-limiting enzyme in ABA biosynthesis), which resulted in greater ABA accumulation in the mesophyll and earlier stomata closure in C. maxima.
登录
查看更多内容
影响因子：
6.9
作者：
Chakraborty K;Bose J;Shabala L;Shabala S
通讯作者：
Shabala S
影响因子：
4
作者：
Demidchik, Vadim;Cuin, Tracey A.;Yurin, Vladimir
通讯作者：
Yurin, Vladimir
影响因子：
11.4
作者：
Hao, Gang-Ping;Zhang, Xiu-Hai;Huang, Cong-Lin
通讯作者：
Huang, Cong-Lin
影响因子：
7.2
作者：
Colmenero-Flores, Jose M.;Martinez, German;Talon, Manuel
通讯作者：
Talon, Manuel
影响因子：
7.2
作者：
Alvarez-Aragon, Rocio;Rodriguez-Navarro, Alonso
通讯作者：
Rodriguez-Navarro, Alonso