College of Animal Science, Guizhou university, Guiyang, Guizhou, China.
Institute of Grassland Research, Sichuan Academy of Grassland Science, Cheng Du, Si Chuan, China.
PLoS One. 2021 Mar 11;16(3):e0240947. doi: 10.1371/journal.pone.0240947. eCollection 2021.
Rocky desertification is a bottleneck that reduces ecological and environmental security in karst areas. Paper mulberry, a unique deciduous tree, shows good performance in rocky desertification areas. Its resistance mechanisms are therefore of high interest. In this study, a lysine acetylation proteomics analysis of paper mulberry seedling leaves was conducted in combination with the purification of acetylated protein by high-precision nano LC-MS/MS. We identified a total of 7130 acetylation sites in 3179 proteins. Analysis of the modified sites showed a predominance of nine motifs. Six positively charged residues: lysine (K), arginine (R), and histidine (H), serine (S), threonine (T), and tyrosine (Y) occurred most frequently at the +1 position, phenylalanine (F) was both detected both upstream and downstream of the acetylated lysines; and the sequence logos showed a strong preference for lysine and arginine around acetylated lysines. Functional annotation revealed that the identified enzymes were mainly involved in translation, transcription, ribosomal structure and biological processes, showing that lysine acetylation can regulate various aspects of primary carbon and nitrogen metabolism and secondary metabolism. Acetylated proteins were enriched in the chloroplast, cytoplasm, and nucleus, and many stress response-related proteins were also discovered to be acetylated, including PAL, HSP70, and ERF. HSP70, an important protein involved in plant abiotic and disease stress responses, was identified in paper mulberry, although it is rarely found in woody plants. This may be further examined in research in other plants and could explain the good adaptation of paper mulberry to the karst environment. However, these hypotheses require further verification. Our data can provide a new starting point for the further analysis of the acetylation function in paper mulberry and other plants.
石漠化是喀斯特地区生态环境安全的瓶颈。桑树是一种独特的落叶乔木，在石漠化地区表现出良好的性能。因此，其抗性机制引起了人们的高度关注。本研究采用赖氨酸乙酰化蛋白质组学分析方法，结合高精度纳升液相色谱-串联质谱（nano LC-MS/MS）对桑树幼苗叶片中的乙酰化蛋白进行了纯化，共鉴定出 3179 个蛋白中的 7130 个乙酰化位点。修饰位点分析表明，9 个基序占主导地位。六个带正电荷的残基：赖氨酸（K）、精氨酸（R）、组氨酸（H）、丝氨酸（S）、苏氨酸（T）和酪氨酸（Y），在+1 位出现的频率最高，苯丙氨酸（F）既出现在乙酰化赖氨酸的上下游；序列标志显示，乙酰化赖氨酸周围强烈偏好赖氨酸和精氨酸。功能注释表明，鉴定出的酶主要参与翻译、转录、核糖体结构和生物过程，表明赖氨酸乙酰化可以调节初级碳氮代谢和次生代谢的各个方面。鉴定出的乙酰化蛋白在叶绿体、细胞质和细胞核中富集，许多与应激反应相关的蛋白质也被发现被乙酰化，包括 PAL、HSP70 和 ERF。HSP70 是一种参与植物非生物和疾病胁迫反应的重要蛋白，在桑树中被鉴定出来，尽管在木本植物中很少发现。这可能需要在其他植物的研究中进一步检验，并解释桑树对喀斯特环境的良好适应。然而，这些假设需要进一步验证。我们的数据可以为进一步分析桑树和其他植物中的乙酰化功能提供新的起点。
