Induction of epidermal cell fate in Arabidopsis shoots

Abstract

Land plants have evolved a cuticle-bearing epidermis to protect themselves from environmental stress and pathogen attack. Despite its important role, little is known about the molecular mechanisms regulating shoot epidermal cell identity. In a recent study, we found that the Arabidopsis thaliana ATML1 gene is possibly a master regulator of shoot epidermal cell fate. We revealed that ATML1 has the ability to confer shoot epidermis-related traits to non-epidermal cells of the seedlings. These data are consistent with the previous loss-of-function mutant analyses, which implied a positive role of ATML1 in epidermal cell differentiation. Importantly, ectopic epidermal cells induced in ATML1-overexpressing lines provide a novel tool to assess the intrinsic properties of epidermal cells and to study epistatic interactions among genes involved in epidermal/mesophyll differentiation. Using this system, we obtained data revealing that ATML1 negatively influenced mesophyll cell fate. In addition, we provided a working model of how division planes in epidermal cells are determined.

Keywords: :

• ATML1
• epidermal cell differentiation
• mesophyll cell differentiation
• HD-ZIP class IV transcription factor
• Arabidopsis thaliana

This article refers to:

Disclosure of Potential Conflicts of Interest

No potential conflicts of interest were disclosed.

Acknowledgments

We especially thank Prof. Tatsuo Kakimoto to permit us to initiate this project in his laboratory. We would like to thank Dr. Shingo Takagi for providing valuable information for this manuscript. This work was supported by the grants from the Japan Society for the Promotion of Science [20657012, 22687003, and 23657036 to S.T.].