School of Life Sciences, Ningxia University, Yinchuan 750021, PR China.
School of Life Sciences, Lanzhou University, Lanzhou 730000, PR China.
J Proteomics. 2021 Apr 15;237:104149. doi: 10.1016/j.jprot.2021.104149. Epub 2021 Feb 12.
Nostoc flagelliforme is a type of terrestrial cyanobacteria that is distributed in arid or semi-arid steppes in China. To research the molecular mechanisms underlying the adaptation of N. flagelliforme to drought stress, the succinylated expression profile and changes in N. flagelliforme that resulted as a response to dehydration were analyzed by label-free proteomics. A total of 1149 succinylated sites, 1128 succinylated peptides, and 396 succinylated proteins were identified. Succinylated proteins were differentially involved in photosynthesis and energy metabolism, as well as in reactive oxygen species (ROS) scavenging. Motif-X analysis of succinylated sites determined a succinylation motif [KxxG]. N. flagelliforme adapts to dehydration by increasing glucose metabolism and pentose phosphate pathway flux, and decreasing photosynthetic rate, which some of the key proteins were succinylated. ROS scavenging was mainly involved in the regulation of the enzyme antioxidant defense system and non-enzymatic antioxidant defense system through succinylation modification, thus eliminating excessive ROS. Protein succinylation of N. flagelliforme may play an important regulatory role in response to dehydration. The results are foundational, as they can inform future research into the mechanisms involved in the succinylation regulation mechanism of N. flagelliforme in response to dehydration. SIGNIFICANCE: The global succinylation network involved in response to dehydration in N. flagelliforme has been established. We found that many succinylated proteins were involved in photosynthesis, glucose metabolism and antioxidation. The global survey of succinylated proteins and the changes of succinylated levels in response to dehydration provided effective information for the drought tolerance mechanism in N. flagelliforme.
发菜是一种陆生蓝藻,分布在中国干旱或半干旱的草原。为了研究发菜适应干旱胁迫的分子机制,采用无标记蛋白质组学方法分析了发菜脱水时的琥珀酰化表达谱和变化。共鉴定到 1149 个琥珀酰化位点、1128 个琥珀酰化肽和 396 个琥珀酰化蛋白。琥珀酰化蛋白差异参与了光合作用和能量代谢,以及活性氧(ROS)清除。琥珀酰化位点的 motif-X 分析确定了一个琥珀酰化基序 [KxxG]。发菜通过增加葡萄糖代谢和戊糖磷酸途径通量,降低光合速率来适应脱水,其中一些关键蛋白发生了琥珀酰化。ROS 清除主要通过琥珀酰化修饰参与调节酶抗氧化防御系统和非酶抗氧化防御系统,从而消除过多的 ROS。发菜蛋白琥珀酰化可能在应对脱水时发挥重要的调节作用。这些结果为进一步研究发菜脱水时琥珀酰化调控机制提供了基础,为揭示发菜适应干旱胁迫的分子机制提供了理论依据。