title: An EAR-Dependent Regulatory Module Promotes Male Germ Cell Division and Sperm Fertility in Arabidopsis.
abstract: The production of the sperm cells in angiosperms requires coordination of cell division and cell differentiation. In Arabidopsis thaliana, the germline-specific MYB protein DUO1 integrates these processes, but the regulatory hierarchy in which DUO1 functions is unknown. Here, we identify an essential role for two germline-specific DUO1 target genes, DAZ1 and DAZ2, which encode EAR motif-containing C2H2-type zinc finger proteins. We show that DAZ1/DAZ2 are required for germ cell division and for the proper accumulation of mitotic cyclins. Importantly, DAZ1/DAZ2 are sufficient to promote G2- to M-phase transition and germ cell division in the absence of DUO1. DAZ1/DAZ2 are also required for DUO1-dependent cell differentiation and are essential for gamete fusion at fertilization. We demonstrate that the two EAR motifs in DAZ1/DAZ2 mediate their function in the male germline and are required for transcriptional repression and for physical interaction with the corepressor TOPLESS. Our findings uncover an essential module in a regulatory hierarchy that drives mitotic transition in male germ cells and implicates gene repression pathways in sperm cell formation and fertility.
authors.affiliation: Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom.
authors.forename: Michael
authors.identifier: http://orcid.org/0000-0002-3982-3843
authors.initials: M
authors.lastname: Borg
authors.affiliation: Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Rutley
authors.affiliation: Agriculture and Agri-Food Canada, Saskatoon SK S7N OX2, Canada.
authors.forename: Sateesh
authors.initials: S
authors.lastname: Kagale
authors.affiliation: JST, ERATO, Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Hamamura
authors.affiliation: Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom.
authors.forename: Mihai
authors.initials: M
authors.lastname: Gherghinoiu
authors.affiliation: Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom.
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom.
authors.forename: Ugur
authors.initials: U
authors.lastname: Sari
authors.affiliation: Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom.
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Esparza-Franco
authors.affiliation: Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Sakamoto
authors.affiliation: Agriculture and Agri-Food Canada, Saskatoon SK S7N OX2, Canada.
authors.forename: Kevin
authors.initials: K
authors.lastname: Rozwadowski
authors.affiliation: JST, ERATO, Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Higashiyama
authors.affiliation: Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom twe@le.ac.uk.
authors.forename: David
authors.identifier: http://orcid.org/0000-0003-0483-1461
authors.initials: D
authors.lastname: Twell