The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University, Rehovot, Israel.
Department of Plant Pathology and Weed Research, Plant Protection Institute, Agricultural Research Organization, Volcani Institute, Rishon LeZion, Israel.
PLoS Genet. 2021 Apr 26;17(4):e1009537. doi: 10.1371/journal.pgen.1009537. eCollection 2021 Apr.
Morphogenesis and differentiation are important stages in organ development and shape determination. However, how they are balanced and tuned during development is not fully understood. In the compound leaved tomato, an extended morphogenesis phase allows for the initiation of leaflets, resulting in the compound form. Maintaining a prolonged morphogenetic phase in early stages of compound-leaf development in tomato is dependent on delayed activity of several factors that promote differentiation, including the CIN-TCP transcription factor (TF) LA, the MYB TF CLAU and the plant hormone Gibberellin (GA), as well as on the morphogenesis-promoting activity of the plant hormone cytokinin (CK). Here, we investigated the genetic regulation of the morphogenesis-differentiation balance by studying the relationship between LA, CLAU, TKN2, CK and GA. Our genetic and molecular examination suggest that LA is expressed earlier and more broadly than CLAU and determines the developmental context of CLAU activity. Genetic interaction analysis indicates that LA and CLAU likely promote differentiation in parallel genetic pathways. These pathways converge downstream on tuning the balance between CK and GA. Comprehensive transcriptomic analyses support the genetic data and provide insights into the broader molecular basis of differentiation and morphogenesis processes in plants.
形态发生和分化是器官发育和形状决定的重要阶段。然而，它们在发育过程中是如何平衡和调节的还不完全清楚。在复叶番茄中，延长的形态发生阶段允许小叶的起始，从而形成复叶形式。在番茄复叶发育的早期阶段维持延长的形态发生阶段依赖于几种促进分化的因子的延迟活性，包括 CIN-TCP 转录因子（TF）LA、MYB TF CLAU 和植物激素赤霉素（GA），以及植物激素细胞分裂素（CK）的形态发生促进活性。在这里，我们通过研究 LA、CLAU、TKN2、CK 和 GA 之间的关系，研究了形态发生-分化平衡的遗传调控。我们的遗传和分子研究表明，LA 的表达比 CLAU 更早、更广泛，决定了 CLAU 活性的发育背景。遗传相互作用分析表明，LA 和 CLAU 可能在平行的遗传途径中促进分化。这些途径在下游汇聚，以调节 CK 和 GA 之间的平衡。综合转录组分析支持遗传数据，并为植物分化和形态发生过程的更广泛分子基础提供了见解。
