Wisniewski Michael E, Bassett Carole L, Renaut Jenny, Farrell Robert, Tworkoski Thomas, Artlip Timothy S
Appalachian Fruit Research Station, USDA-ARS, 2217 Wiltshire Road, Kearneysville, WV 25430, USA.
Tree Physiol. 2006 May;26(5):575-84. doi: 10.1093/treephys/26.5.575.
Dehydrins are one of several proteins that have been specifically associated with qualitative and quantitative changes in cold hardiness. Recent evidence indicates that the regulation of dehydrin genes by low nonfreezing temperature (LT) and short photoperiod (SD) can be complex and deserves more detailed analysis to better understand the role of specific dehydrin genes and proteins in the response of woody plants to environmental stress. We have identified a new peach (Prunus persica (L.) Batsch) dehydrin gene (PpDhn2) and examined the responses of this gene and a previously identified dehydrin (PpDhn1) to SD, LT and water deficit. PpDhn2 was strongly induced by water deficit but not by LT or SD. It was also present in the mature embryos of peach. In contrast, PpDhn1 was induced by water deficit and LT but not by SD. We conducted an in silico analysis of the promoters of these genes and found that the promoter region of PpDhn1 contained two dehydration-responsive-elements (DRE)/C-repeats that are responsive to LT and several abscisic acid (ABA)-response elements (ABREs). In contrast, the promoter region of PpDhn2 contained no LT elements but contained several ABREs and an MYCERD1 motif. Both promoter analyses were consistent with the observed expression patterns. The discrepancy between field-collected samples and growth-chamber experiments in the expression of PpDhn1 in response to SD suggests that SD-induced expression of dehydrin genes is complex and may be the result of several interacting factors.
脱水素是几种与抗寒能力的定性和定量变化有特定关联的蛋白质之一。最近的证据表明，低非冰冻温度（LT）和短光周期（SD）对脱水素基因的调控可能很复杂，值得进行更详细的分析，以便更好地理解特定脱水素基因和蛋白质在木本植物对环境胁迫的响应中的作用。我们鉴定了一个新的桃（Prunus persica (L.) Batsch）脱水素基因（PpDhn2），并研究了该基因以及先前鉴定的脱水素（PpDhn1）对SD、LT和水分亏缺的响应。PpDhn2受到水分亏缺的强烈诱导，但不受LT或SD的诱导。它也存在于桃的成熟胚中。相比之下，PpDhn1受到水分亏缺和LT的诱导，但不受SD的诱导。我们对这些基因的启动子进行了电子分析，发现PpDhn1的启动子区域包含两个对LT有响应的脱水响应元件（DRE）/C重复序列以及几个脱落酸（ABA）响应元件（ABRE）。相比之下，PpDhn2的启动子区域不包含LT元件，但包含几个ABRE和一个MYCERD1基序。两种启动子分析都与观察到的表达模式一致。田间采集样本与生长室实验中PpDhn1对SD响应的表达差异表明，SD诱导的脱水素基因表达很复杂，可能是几种相互作用因素的结果。
