Table_1_Identification and analysis of lignin biosynthesis genes related to fruit ripening and stress response in banana (Musa acuminata L. AAA group, cv. Cavendish).xlsx

BackgroundLignin is a key component of the secondary cell wall of plants, providing mechanical support and facilitating water transport as well as having important impact effects in response to a variety of biological and abiotic stresses.
ResultsIn this study, we identified 104 genes from ten enzyme gene families related to lignin biosynthesis in Musa acuminata genome and found the number of MaCOMT gene family was the largest, while MaC3Hs had only two members. MaPALs retained the original members, and the number of Ma4CLs in lignin biosynthesis was significantly less than that of flavonoids. Segmental duplication existed in most gene families, except for MaC3Hs, and tandem duplication was the main way to expand the number of MaCOMTs. Moreover, the expression profiles of lignin biosynthesis genes during fruit development, postharvest ripening stages and under various abiotic and biological stresses were investigated using available RNA-sequencing data to obtain fruit ripening and stress response candidate genes. Finally, a co-expression network of lignin biosynthesis genes was constructed by weighted gene co-expression network analysis to elucidate the lignin biosynthesis genes that might participate in lignin biosynthesis in banana during development and in response to stresses.
ConclusionThis study systematically identified the lignin biosynthesis genes in the Musa acuminata genome, providing important candidate genes for further functional analysis. The identification of the major genes involved in lignin biosynthesis in banana provides the basis for the development of strategies to improve new banana varieties tolerant to biological and abiotic stresses with high yield and high quality.

研究背景：木质素（Lignin）是植物次生细胞壁的关键组成成分，可为植物提供机械支撑并促进水分运输，同时在应对多种生物与非生物胁迫过程中发挥重要调控作用。
研究结果：本研究从小果野蕉（Musa acuminata）基因组中鉴定得到104个与木质素生物合成相关的酶编码基因，分属10个酶基因家族。其中，MaCOMT基因家族的成员数量最多，而MaC3Hs家族仅包含2个成员；MaPALs家族的成员数保持原始水平，且木质素生物合成通路中的Ma4CL家族成员数量显著少于类黄酮通路中的该家族成员。除MaC3Hs家族外，多数基因家族均存在片段重复事件，而MaCOMT家族的基因扩张主要通过串联重复实现。此外，本研究利用现有RNA测序（RNA-sequencing）数据，分析了木质素生物合成基因在香蕉果实发育、采后成熟阶段以及多种生物与非生物胁迫下的表达谱，以筛选获得参与果实成熟及胁迫响应的候选基因。最后，通过加权基因共表达网络分析（weighted gene co-expression network analysis）构建了木质素生物合成基因的共表达网络，以阐明参与香蕉发育及胁迫响应过程中的木质素生物合成相关基因。
研究结论：本研究系统鉴定了小果野蕉基因组中的木质素生物合成相关基因，为后续功能分析提供了重要的候选基因资源。对香蕉木质素生物合成核心基因的鉴定，可为培育高产、优质且兼具生物与非生物胁迫耐受性的香蕉新品种提供理论依据与策略开发基础。