State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, People's Republic of China.
BMC Plant Biol. 2018 Oct 4;18(1):218. doi: 10.1186/s12870-018-1416-0.
Zinc-finger transcription factors play central roles in plant growth, development and abiotic stress responses. PLATZ encodes a class of plant-specific zinc-finger transcription factor. However, biological functions or physiological mechanism controlled by PLATZ are currently limited.
GhPLATZ1 transcripts were considerably up-regulated by NaCl, mannitol, abscisic acid (ABA) and gibberellin (GA) treatments. Transgenic Arabidopsis by ectopic expression of GhPLATZ1 exhibited faster seed germination and higher seedling establishment under salt and mannitol stresses than those of wild type (WT), indicating enhanced osmotic insensitivity in GhPLATZ1 transgenic Arabidopsis. The ABA content in dry seeds of GhPLATZ1 transgenic Arabidopsis was lower than that of WT whereas the ABA content was not changed in germinating seeds under salt stress. Seed germination was faster than but the seedling establishment of transgenic Arabidopsis was similar to WT. Besides, GhPLATZ1 transgenic and WT Arabidopsis exhibited insensitivity to paclobutrazol (PAC), a GA biosynthesis inhibitor, whereas exogenous GA could eliminate the growth difference between GhPLATZ1 transgenic and WT Arabidopsis under salt stress. Moreover, exogenous 1-aminocyclopropane-1-carboxylic acid (ACC), an ethylene precursor, exerted similar effects to GA. Furthermore, ABI4 and ETO1 transcripts were significantly down-regulated, whereas ACS8 was up-regulated in GhPLATZ1 transgenic Arabidopsis under salt stress.
In conclusion, GhPLATZ1 had broad influence in responses to salt and mannitol stresses in transgenic Arabidopsis during seed germination and seedling establishment. The effect of GhPLATZ1 expression in transgenic Arabidopsis might be mediated by the ABA, GA, and ethylene pathways. Thus, this study provided new insights into the regulatory network in response to abiotic stresses in plants.
锌指转录因子在植物生长、发育和非生物胁迫响应中发挥核心作用。PLATZ 编码一类植物特异性锌指转录因子。然而，目前受 PLATZ 控制的生物学功能或生理机制还很有限。
GhPLATZ1 转录本在 NaCl、甘露醇、脱落酸（ABA）和赤霉素（GA）处理下显著上调。过表达 GhPLATZ1 的转基因拟南芥在盐和甘露醇胁迫下表现出更快的种子萌发和更高的幼苗成活率，比野生型（WT）更耐渗透胁迫，表明 GhPLATZ1 转基因拟南芥的渗透敏感性增强。GhPLATZ1 转基因拟南芥干种子中的 ABA 含量低于 WT，而在盐胁迫下萌发种子中的 ABA 含量没有变化。种子萌发比 WT 快，但幼苗建立与 WT 相似。此外，GhPLATZ1 转基因和 WT 拟南芥对多效唑（PAC）不敏感，PAC 是一种 GA 生物合成抑制剂，而外源 GA 可以消除盐胁迫下 GhPLATZ1 转基因和 WT 拟南芥之间的生长差异。此外，乙烯前体 1-氨基环丙烷-1-羧酸（ACC）也有类似 GA 的作用。此外，在盐胁迫下，GhPLATZ1 转基因拟南芥中 ABI4 和 ETO1 转录本显著下调，而 ACS8 转录本上调。
总之，GhPLATZ1 在种子萌发和幼苗建立过程中对转基因拟南芥的盐和甘露醇胁迫反应有广泛的影响。GhPLATZ1 表达在转基因拟南芥中的作用可能是通过 ABA、GA 和乙烯途径介导的。因此，本研究为植物应对非生物胁迫的调控网络提供了新的见解。
