Key message

An allene oxide cyclase gene which is involved in defense against biotic and abiotic stresses was cloned and characterized in sugarcane.

Abstract

Allene oxide cyclase (AOC), a key enzyme in jasmonate acid (JA) biosynthesis, affects the stereoisomerism and biological activity of JA molecules, and plays an important role in plant stress resistance. In this study, four SsAOC alleles (SsAOC1–SsAOC4), which shared similar gene structure and were located on Chr1A, Chr1B, Chr1C, and Chr1D, respectively, were mined from sugarcane wild species Saccharum spontaneum, and a homologous gene ScAOC1 (GenBank Accession Number: MK674849) was cloned from sugarcane hybrid variety Yacheng05-179 inoculated with Sporisorium scitamineum for 48 h. ScAOC1 and SsAOC1–SsAOC4 were alkaline, unstable, hydrophilic, and non-secretory proteins, which possess the same set of conserved motifs and were clustered into one group in the phylogenetic analysis. ScAOC1 was expressed in all sugarcane tissues, but with different levels. After infection by S. scitamineum, the transcripts of ScAOC1 were increased significantly both in the smut-susceptible (ROC22) and resistant (Yacheng05-179) varieties, but its transcripts were more accumulated and lasted for a longer period in the smut-resistant variety than in the smut-susceptible one. ScAOC1 was down-regulated under MeJA and NaCl treatments, but up-regulated under SA, ABA, PEG, and cold stresses. Transiently overexpressing ScAOC1 gene into Nicotiana benthamiana leaves regulated the responses of N. benthamiana to two pathogens Ralstonia solanacearum and Fusarium solani var. coeruleum. Furthermore, prokaryotic expression analysis showed overexpression of ScAOC1 in Escherichia coli BL21 could enhance its tolerance to NaCl, mannitol, and cold stimuli. These results indicated that ScAOC1 may play an active role in response to biotic and abiotic stresses in sugarcane.

中文翻译：

---

ScAOC1，一种丙二烯氧化环化酶基因，赋予甘蔗对生物和非生物胁迫的防御反应。

关键信息

在甘蔗中克隆并表征了参与防御生物和非生物胁迫的丙二烯氧化环化酶基因。

抽象的

烯化氧环化酶（AOC）是茉莉酸（JA）生物合成的关键酶，影响JA分子的立体异构和生物活性，在植物抗逆性中发挥重要作用。本研究从甘蔗野生种Saccharum spontaneum和同源基因ScAOC1（GenBank Accession编号：MK674849) 是从甘蔗杂交品种Yacheng05-179 中克隆出Sporisorium scitamineum48 小时。ScAOC1 和 SsAOC1–SsAOC4 是碱性的、不稳定的、亲水的和非分泌蛋白，它们具有相同的一组保守基序，并且在系统发育分析中聚集成一个组。ScAOC1在所有甘蔗组织中均有表达，但水平不同。s. scitamineum侵染后, ScAOC1的转录本在黑穗病敏感(ROC22) 和抗性(Yacheng05-179) 品种中均显着增加, 但其转录本在黑穗病中积累较多, 持续时间较长。比在黑粉病易感者中。ScAOC1在 MeJA 和 NaCl 处理下下调，但在 SA、ABA、PEG 和冷胁迫下上调。瞬时过度表达本氏烟草叶片中的ScAOC1基因调节了本氏烟草对两种病原体Ralstonia solanacearum和Fusarium solani var 的反应。蓝斑。此外，原核表达分析表明，ScAOC1在大肠杆菌BL21 中的过表达可以增强其对NaCl、甘露醇和冷刺激的耐受性。这些结果表明，ScAOC1可能在甘蔗的生物和非生物胁迫中发挥积极作用。