bHLH heterodimer complex variations regulate cell proliferation activity in the meristems of Arabidopsis thaliana

Eliana Mor; Markéta Pernisová; Max Minne; Guillaume Cerutti; Dagmar Ripper; Jonah Nolf; Jennifer Andres; Laura Ragni; Matias D Zurbriggen; Bert De Rybel; Teva Vernoux

doi:10.1016/j.isci.2022.105364

bHLH heterodimer complex variations regulate cell proliferation activity in the meristems of Arabidopsis thaliana

iScience. 2022 Oct 14;25(11):105364. doi: 10.1016/j.isci.2022.105364. eCollection 2022 Nov 18.

Authors

Eliana Mor^{1

2}, Markéta Pernisová^{3

4

5}, Max Minne^{1

2}, Guillaume Cerutti³, Dagmar Ripper⁶, Jonah Nolf^{1

2}, Jennifer Andres⁵, Laura Ragni⁶, Matias D Zurbriggen⁵, Bert De Rybel^{1

2}, Teva Vernoux³

Affiliations

¹ Ghent University, Department of Plant Biotechnology and Bioinformatics, Technologiepark 71, 9052 Ghent, Belgium.
² VIB Centre for Plant Systems Biology, Technologiepark 71, 9052 Ghent, Belgium.
³ Laboratoire Reproduction et Développement des Plantes, University Lyon, ENS de Lyon, CNRS, INRAE, INRIA, 69342 Lyon, France.
⁴ Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, and Plant Sciences Core Facility, Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, 62500 Brno, Czechia.
⁵ Institute of Synthetic Biology and CEPLAS, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
⁶ ZMBP-Center for Plant Molecular Biology, University of Tübingen, Auf der Morgenstelle 32, 72076 Tübingen, Germany.

Abstract

Root, shoot, and lateral meristems are the main regions of cell proliferation in plants. It has been proposed that meristems might have evolved dedicated transcriptional networks to balance cell proliferation. Here, we show that basic helix-loop-helix (bHLH) transcription factor heterodimers formed by members of the TARGET OF MONOPTEROS5 (TMO5) and LONESOME HIGHWAY (LHW) subclades are general regulators of cell proliferation in all meristems. Yet, genetics and expression analyses suggest specific functions of these transcription factors in distinct meristems, possibly due to their expression domains determining heterodimer complex variations within meristems, and to a certain extent to the absence of some of them in a given meristem. Target gene specificity analysis for heterodimer complexes focusing on the LONELY GUY gene targets further suggests differences in transcriptional responses through heterodimer diversification that could allow a common bHLH heterodimer complex module to contribute to cell proliferation control in multiple meristems.

Keywords: Biological sciences; Molecular plant pathology; Natural sciences; Plant biology.