近日，英国剑桥大学Julian M. Hibberd等研究人员合作发现，与MYB相关的转录因子控制叶绿体的生物发生。2024年7月23日，国际知名学术期刊《细胞》在线发表了这一成果。
研究人员鉴定了MYB相关转录因子作为蕨类植物地钱（Marchantia polymorpha）和被子植物拟南芥（Arabidopsis thaliana）中，叶绿体生物合成的调节因子。在这两种植物中，MYB相关基因的双突变体表现出非常有限的叶绿体发育，并且光合作用基因的表达受到的干扰程度大于GOLDEN2-LIKE（GLK）突变体。
MYB相关蛋白和GLK蛋白共同控制了叶绿素生物合成的酶编码基因，而那些涉及CO2固定、光呼吸以及光系统组装和修复的基因则需要MYB相关蛋白的调控。在拟南芥中，MYB相关转录因子与GLK之间的调控关系似乎比地钱中更加广泛。因此，MYB相关和GLK基因具有重叠和独特的靶标。研究人员认为，MYB相关和GLK转录因子在陆生植物中共同协调叶绿体发育。
据介绍，叶绿体生物合成依赖于来自GLK转录因子家族的主调节因子。然而，glk突变体仍含有残余叶绿素，表明其他蛋白质必定参与其中。
附：英文原文
Title: MYB-related transcription factors control chloroplast biogenesis
Author: Eftychios Frangedakis, Nataliya E. Yelina, Kumari Billakurthi, Lei Hua, Tina Schreier, Patrick J. Dickinson, Marta Tomaselli, Jim Haseloff, Julian M. Hibberd
Issue&Volume: 2024-07-23
Abstract: Chloroplast biogenesis is dependent on master regulators from the GOLDEN2-LIKE (GLK) family of transcription factors. However, glk mutants contain residual chlorophyll, indicating that other proteins must be involved. Here, we identify MYB-related transcription factors as regulators of chloroplast biogenesis in the liverwort Marchantia polymorpha and angiosperm Arabidopsis thaliana. In both species, double-mutant alleles in MYB-related genes show very limited chloroplast development, and photosynthesis gene expression is perturbed to a greater extent than in GLK mutants. Genes encoding enzymes of chlorophyll biosynthesis are controlled by MYB-related and GLK proteins, whereas those allowing CO2 fixation, photorespiration, and photosystem assembly and repair require MYB-related proteins. Regulation between the MYB-related and GLK transcription factors appears more extensive in A. thaliana than in M. polymorpha. Thus, MYB-related and GLK genes have overlapping as well as distinct targets. We conclude that MYB-related and GLK transcription factors orchestrate chloroplast development in land plants.
DOI: 10.1016/j.cell.2024.06.039
Source: https://www.cell.com/cell/fulltext/S0092-8674(24)00713-X