title: NRPB3, the third largest subunit of RNA polymerase II, is essential for stomatal patterning and differentiation in Arabidopsis.
abstract: Stomata are highly specialized epidermal structures that control transpiration and gas exchange between plants and the environment. Signal networks underlying stomatal development have been previously uncovered but much less is known about how signals involved in stomatal development are transmitted to RNA polymerase II (Pol II or RPB), which plays a central role in the transcription of mRNA coding genes. Here, we identify a partial loss-of-function mutation of the third largest subunit of nuclear DNA-dependent Pol II (NRPB3) that exhibits an increased number of stomatal lineage cells and paired stomata. Phenotypic and genetic analyses indicated that NRPB3 is not only required for correct stomatal patterning, but is also essential for stomatal differentiation. Protein-protein interaction assays showed that NRPB3 directly interacts with two basic helix-loop-helix (bHLH) transcription factors, FAMA and INDUCER OF CBF EXPRESSION1 (ICE1), indicating that NRPB3 serves as an acceptor for signals from transcription factors involved in stomatal development. Our findings highlight the surprisingly conserved activating mechanisms mediated by the third largest subunit of Pol II in eukaryotes.
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Liping
authors.initials: L
authors.lastname: Guan
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Qian
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Fan
authors.initials: F
authors.lastname: Xu
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Yujun
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: He
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Gou
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China housw@lzu.edu.cn.
authors.forename: Suiwen
authors.initials: S
authors.lastname: Hou
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000196:embryology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics; D012321:DNA-Directed RNA Polymerases / Q000235:genetics*; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D054046:Plant Stomata / Q000166:cytology / Q000196:embryology*; D025941:Protein Interaction Mapping; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; D012321:DNA-Directed RNA Polymerases; D014157:Transcription Factors; C517481:FAMA protein, Arabidopsis; C510502:ICE1 protein, Arabidopsis; C507999:Myb88 protein, Arabidopsis; C568761:NRPD1A protein, Arabidopsis
keywords: Arabidopsis; Differentiation; Patterning; RNA polymerase II; Stomata