盐胁迫下桑树种子萌发的生理和蛋白质组学分析。

Physiological and Proteomic Analysis of Seed Germination under Salt Stress in Mulberry.

机构信息

College of Horticulture and Landscape Architecture, Zhongkai University of Agriculture and Engineering, 510225 Guangzhou, Guangdong, China.

出版信息

Front Biosci (Landmark Ed). 2023 Mar 13;28(3):49. doi: 10.31083/j.fbl2803049.

DOI:10.31083/j.fbl2803049

PMID:37005750

Abstract

BACKGROUND

Salinity is the main abiotic stress that affects seed germination, plant growth and crop production. Plant growth begins with seed germination, which is closely linked to crop development and final yields. L. is a well-known saline-alkaline tree with economic value in China, and the most prominent method of expanding mulberry tree populations is seed propagation. Understanding the molecular mechanism of L. salt tolerance is crucial for identifying salt-tolerant proteins in seed germination. Here, we explored the response mechanism of mulberry seed germination to salt stress at physiological and protein omics levels.

METHODS

Tandem mass tag (TMT)-based proteomic profiling of L. seeds germinated under 50 mM and 100 mM NaCl treatment for 14 days was performed, and the proteomic findings were validated through parallel reaction monitoring (PRM).

RESULTS

Physiological data showed that salt stress inhibited the germination rate and radicle length of mulberry seeds, decreased the malondialdehyde (MDA) content and significantly increased superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities. Then, a TMT marker technique was used to analyze the protein groups in mulberry seeds with two salt treatment stages, and 76,544 unique peptides were detected. After removing duplicate proteins, 7717 proteins were identified according to TMT data, and 143 (50 mM NaCl) and 540 (100 mM NaCl) differentially abundant proteins (DAPs) were screened out. Compared with the control, in the 50 mM NaCl solution, 61 and 82 DAPs were upregulated and downregulated, respectively, and in the 100 mM NaCl solution, 222 and 318 DAPs were upregulated and downregulated, respectively. Furthermore, 113 DAPs were copresent in the 50 mM and 100 mM NaCl treatments, of which 43 were upregulated and 70 were downregulated. Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the DAPs induced by salt stress during mulberry seed germination were mainly involved in photosynthesis, carotenoid biosynthesis and phytohormone signaling. Finally, PRM verified five differentially expressed proteins, which demonstrated the reliability of TMT in analyzing protein groups.

CONCLUSIONS

Our research provides valuable insights to further study the overall mechanism of salt stress responses and salt tolerance of mulberry and other plants.

摘要

背景

盐度是影响种子萌发、植物生长和作物产量的主要非生物胁迫因素。植物生长始于种子萌发，这与作物的发育和最终产量密切相关。L.是一种在中国具有经济价值的耐盐碱性树种，扩大桑树种群最突出的方法是种子繁殖。了解 L.的耐盐分子机制对于鉴定种子萌发过程中的耐盐蛋白至关重要。在这里，我们从生理和蛋白质组学水平上探讨了桑树种子对盐胁迫的响应机制。

方法

对在 50mM 和 100mM NaCl 处理下发芽 14 天的 L.种子进行串联质量标签（TMT）蛋白组学分析，并通过平行反应监测（PRM）验证蛋白质组学结果。

结果

生理数据表明，盐胁迫抑制了桑树种子的萌发率和胚根长度，降低了丙二醛（MDA）含量，显著增加了超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）的活性。然后，使用 TMT 标记技术分析了具有两个盐处理阶段的桑树种子的蛋白质组，检测到 76544 个独特肽段。去除重复蛋白后，根据 TMT 数据鉴定出 7717 种蛋白质，筛选出 143 种（50mM NaCl）和 540 种（100mM NaCl）差异丰度蛋白（DAP）。与对照相比，在 50mM NaCl 溶液中，分别有 61 种和 82 种 DAP 上调和下调，在 100mM NaCl 溶液中，分别有 222 种和 318 种 DAP 上调和下调。此外，在 50mM 和 100mM NaCl 处理中共有 113 种 DAP，其中 43 种上调，70 种下调。GO 注释和京都基因与基因组百科全书（KEGG）富集分析表明，盐胁迫诱导的 DAPs 在桑树种子萌发过程中主要参与光合作用、类胡萝卜素生物合成和植物激素信号转导。最后，PRM 验证了 5 种差异表达蛋白，这表明 TMT 分析蛋白质组的可靠性。