2024-06-24 マックス・プランク研究所
<関連情報>
- https://www.mpg.de/22119165/gene-switch-leave-shape
- https://www.pnas.org/doi/10.1073/pnas.2321877121
アブラナ科植物において、CUC1/auxin遺伝モジュールが細胞の極性をパターン化された組織成長と葉の形状の多様性に結びつけていることを発見 A CUC1/auxin genetic module links cell polarity to patterned tissue growth and leaf shape diversity in crucifer plants
Zi-Liang Hu, David Wilson-Sánchez, Neha Bhatia, +9, and Miltos Tsiantis
Proceedings of the National Academy of Sciences Published:June 21, 2024
DOI:https://doi.org/10.1073/pnas.2321877121
Significance
How spatially distributed gene activities are translated into the patterns of cell polarity and growth that generate the diverse forms of multicellular eukaryotes remains poorly understood. Here, we show that species-specific expression of the transcription factor CUP-SHAPED COTYLEDON1 (CUC1) is a key determinant of leaf-shape differences between two related plant species. By combining time-lapse imaging, genetics, and modeling, we found that CUC1 acts as a polarity switch. This switch regulates leaf shape through transcriptional activation of kinases that influence the polarity of auxin transporters, which pattern leaf growth through feedback with the hormone auxin. Thus, we have uncovered a mechanism that bridges biological scales by linking species-specific transcription factor expression to cell-level polarity and growth, to shape diverse leaf forms.
Abstract
How tissue-level information encoded by fields of regulatory gene activity is translated into the patterns of cell polarity and growth that generate the diverse shapes of different species remains poorly understood. Here, we investigate this problem in the case of leaf shape differences between Arabidopsis thaliana, which has simple leaves, and its relative Cardamine hirsuta that has complex leaves divided into leaflets. We show that patterned expression of the transcription factor CUP-SHAPED COTYLEDON1 in C. hirsuta (ChCUC1) is a key determinant of leaf shape differences between the two species. Through inducible genetic perturbations, time-lapse imaging of growth, and computational modeling, we find that ChCUC1 provides instructive input into auxin-based leaf margin patterning. This input arises via transcriptional regulation of multiple auxin homeostasis components, including direct activation of WAG kinases that are known to regulate the polarity of PIN-FORMED auxin transporters. Thus, we have uncovered a mechanism that bridges biological scales by linking spatially distributed and species-specific transcription factor expression to cell-level polarity and growth, to shape diverse leaf forms.
