Zhou Man, Luo Hong
Department of Genetics and Biochemistry; Clemson University; Clemson, SC USA.
Plant Signal Behav. 2014;9(4):e28700. doi: 10.4161/psb.28700. Epub 2014 Apr 3.
The microRNA319 family (miR319) is one of the most conserved and ancient microRNA (miRNA) families in plants. Transgenic creeping bentgrass (Agrostis stolonifera) overexpressing a rice miR319, Osa-miR319a, exhibited enhanced salt and drought tolerance. A comprehensive hypothetical model about the role of miR319 in creeping bentgrass response to salinity and drought stress was proposed. Salinity and drought stress induces elevated expression of miR319, resulting in downregulation of at least 4 putative target genes of miR319 (AsPCF5, AsPCF6, AsPCF8, and AsTCP14) as well as a homolog of the rice NAC domain gene AsNAC60, and therefore positively contributing to plant abiotic stress response. Hormones might also regulate miR319 and its targets, and the expression level of the miR319 targets might be a balance of miR319-mediated target cleavage and hormone regulation of the targets. Furthermore, HKT gene families involved in salt exclusion mechanisms as well as mechanisms controlling the timing of gene expression network are also hypothesized to play an important role in this pathway.
微小RNA319家族（miR319）是植物中最保守、最古老的微小RNA（miRNA）家族之一。过表达水稻miR319（Osa-miR319a）的转基因匍匐翦股颖（Agrostis stolonifera）表现出增强的耐盐性和耐旱性。提出了一个关于miR319在匍匐翦股颖对盐度和干旱胁迫响应中作用的综合假设模型。盐度和干旱胁迫诱导miR319表达升高，导致miR319的至少4个假定靶基因（AsPCF5、AsPCF6、AsPCF8和AsTCP14）以及水稻NAC结构域基因AsNAC60的一个同源物表达下调，因此对植物非生物胁迫响应有积极贡献。激素也可能调节miR319及其靶标，并且miR319靶标的表达水平可能是miR319介导的靶标切割和激素对靶标的调节之间的平衡。此外，参与排盐机制以及控制基因表达网络时间的HKT基因家族也被假设在该途径中起重要作用。
