Bai Zhenqing, Xia Pengguo, Wang Ruilin, Jiao Jie, Ru Mei, Liu Jingling, Liang Zongsuo
College of Life Science, Northwest A&F University, Yangling, China.
College of Life Science, Zhejiang Sci-Tech University, Hangzhou, China.
PLoS One. 2017 Sep 27;12(9):e0185322. doi: 10.1371/journal.pone.0185322. eCollection 2017.
The gibberellin-responsive element binding factor (GRAS) family of proteins plays an important role in the transcriptional regulation of plant development and hormone signaling. To date, there are no reports on GRAS family proteins expressed in Salvia miltiorrhiza. In this study, 28 ESTs that contained the GRAS domain were identified from a S. miltiorrhiza cDNA library. Of these, full-length sequences of five genes were cloned and sequence analysis indicated that all five proteins contain only one GRAS domain and therefore, belong to the GRAS family. The five genes were designated S. miltiorrhiza GRAS1-5 (SmGRAS1-5), which belong to groups I (SmGRAS2 and SmGRAS4), II (SmGRAS3), III (SmGRAS1), and VIII (SmGRAS5) respectively. Additionally, SmGRAS1-5 have different expression patterns in the reed head, stems, leaves, flowers, and roots of S. miltiorrhiza. In this study, the expression of SmGRAS1-5 was sensitive to Gibberellin (GA) stress and that of SmGRAS1, SmGRAS4 and SmGRAS5 was sensitive to Ethephon (Eth) stress respectively. Moreover, S. miltiorrhiza copalyl diphosphate synthases 1 (SmCPS1) and S. miltiorrhiza kaurene synthase like 1 (SmKSL1), which are two key enzymes gene in the diterpenoid biosynthesis pathway, were also response to GA and Eth stress. In addition, Dihydrotanshinone (DT-I) and Tanshinone I (T-I) content were enhanced by GA and Eth stress, Tanshinone IIA (T-IIA) content was increased by GA stress, and the accumulation of Cryptotanshinone (CT) was insensitive to both GA and Eth stress. Together, these results provide insights into functional conservation and diversification of SmGRASs and are useful information for further elucidating SmGRAS functions.
赤霉素响应元件结合因子（GRAS）蛋白家族在植物发育和激素信号的转录调控中发挥着重要作用。迄今为止，尚无关于丹参中表达的GRAS家族蛋白的报道。在本研究中，从丹参cDNA文库中鉴定出28个含有GRAS结构域的EST。其中，克隆了5个基因的全长序列，序列分析表明这5种蛋白均仅含有一个GRAS结构域，因此属于GRAS家族。这5个基因分别命名为丹参GRAS1 - 5（SmGRAS1 - 5），它们分别属于第I组（SmGRAS2和SmGRAS4）、第II组（SmGRAS3）、第III组（SmGRAS1）和第VIII组（SmGRAS5）。此外，SmGRAS1 - 5在丹参的芦头、茎、叶、花和根中具有不同的表达模式。在本研究中，SmGRAS1 - 5的表达对赤霉素（GA）胁迫敏感，而SmGRAS1、SmGRAS4和SmGRAS5的表达分别对乙烯利（Eth）胁迫敏感。此外，丹参柯巴基二磷酸合酶1（SmCPS1）和丹参贝壳杉烯合酶类似物1（SmKSL1）是二萜生物合成途径中的两个关键酶基因，它们也对GA和Eth胁迫有响应。另外，GA和Eth胁迫可提高二氢丹参酮（DT - I）和丹参酮I（T - I）的含量，GA胁迫可增加丹参酮IIA（T - IIA）的含量，但隐丹参酮（CT）的积累对GA和Eth胁迫均不敏感。总之，这些结果为深入了解SmGRASs的功能保守性和多样性提供了线索，为进一步阐明SmGRAS的功能提供了有用信息。
