Expression profiles of four BES1/ BZR1 homologous genes encoding bHLH transcription factors in Arabidopsis

Yui Otani; Yusuke Tomonaga; Kenya Tokushige; Miyu Kamimura; Azusa Sasaki; Yasushi Nakamura; Takako Nakamura; Tomoaki Matsuo; Shigehisa Okamoto

doi:10.1584/jpestics.D20-001

Expression profiles of four BES1/ BZR1 homologous genes encoding bHLH transcription factors in Arabidopsis

J Pestic Sci. 2020 May 20;45(2):95-104. doi: 10.1584/jpestics.D20-001.

Authors

Yui Otani¹, Yusuke Tomonaga¹, Kenya Tokushige¹, Miyu Kamimura¹, Azusa Sasaki², Yasushi Nakamura³, Takako Nakamura², Tomoaki Matsuo¹, Shigehisa Okamoto¹

Affiliations

¹ The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan.
² Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan.
³ Department of Japanese Food Culture, Faculty of Letters, Kyoto Prefectural University, Kyoto, Japan.

Abstract

Arabidopsis bHLH-type transcription factors-BRASSINOSTEROID INSENSITIVE 1-EMS-SUPPRESSOR 1 (BES1) and BRASSINAZOLE RESISTANT 1 (BZR1)-play key roles in brassinosteroid (BR) signaling. By contrast, the functions of the other four BES1/BZR1 homologs (BEH1-4) remain unknown. Here, we describe the detailed expression profiles of the BES1/BZR1 family genes. Their expressions were distinct regarding growth-stage dependence and organ specificity but exhibited some overlaps as well. Furthermore, their mRNA levels mostly remained unchanged responding to seven non-BR phytohormones. However, BEH1 and BEH2 were downregulated by brassinolide, suggesting a close association with the BR function. Additionally, BEH4 was ubiquitously expressed throughout the life of the plant but displayed some expression preference. For instance, BEH4 expression was limited to guard cells and the adjacent pavement cells in the leaf epidermis and was induced during growth progression in very young seedlings, suggesting that BEH4 is specifically regulated in certain contexts, although it is almost constitutively controlled.

Keywords: BES1/BZR1 homologs (BEH); brassinolide; brassinosteroids; stomata; β-glucuronidase (GUS).

© Pesticide Science Society of Japan 2020. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) License (https://creativecommons.org/licenses/by-nc-nd/4.0/).