Transcriptional regulation of PIN genes by FOUR LIPS and MYB88 during Arabidopsis root gravitropism.

Hong-Zhe Wang,Fred Sack,Jun-Jie Zou,Jiří Friml,Tom Beeckman,Steffen Vanneste,Ling-Ling Zhu,Zi Dian Xie,Masao Tasaka,Miyo Terao Morita,Ke-Zhen Yang,Jie Le,Erich Grotewold

doi:10.1038/ncomms9822

Abstract

PIN proteins are auxin export carriers that direct intercellular auxin flow and in turn regulate many aspects of plant growth and development including responses to environmental changes. The Arabidopsis R2R3-MYB transcription factor FOUR LIPS (FLP) and its paralogue MYB88 regulate terminal divisions during stomatal development, as well as female reproductive development and stress responses. Here we show that FLP and MYB88 act redundantly but differentially in regulating the transcription of PIN3 and PIN7 in gravity-sensing cells of primary and lateral roots. On the one hand, FLP is involved in responses to gravity stimulation in primary roots, whereas on the other, FLP and MYB88 function complementarily in establishing the gravitropic set-point angles of lateral roots. Our results support a model in which FLP and MYB88 expression specifically determines the temporal-spatial patterns of PIN3 and PIN7 transcription that are closely associated with their preferential functions during root responses to gravity.

Highlights

PIN proteins are auxin export carriers that direct intercellular auxin flow and in turn regulate many aspects of plant growth and development including responses to environmental changes
We show that the Arabidopsis R2R3-MYB transcription factor FOUR LIPS (FLP) and its paralogue MYB88 directly regulate transcription levels of the PIN3 and PIN7 genes, a regulation that in turn mediates auxin transport that contributes to the gravitropic responses of primary and lateral roots
Our results support a model in which FLP and MYB88 determines the temporal-spatial patterns of PIN3 and PIN7 transcription that are closely associated with their preferential functions during root responses to gravity

Summary

Introduction

PIN proteins are auxin export carriers that direct intercellular auxin flow and in turn regulate many aspects of plant growth and development including responses to environmental changes. We show that FLP and MYB88 act redundantly but differentially in regulating the transcription of PIN3 and PIN7 in gravity-sensing cells of primary and lateral roots. Our results support a model in which FLP and MYB88 expression determines the temporal-spatial patterns of PIN3 and PIN7 transcription that are closely associated with their preferential functions during root responses to gravity. We show that the Arabidopsis R2R3-MYB transcription factor FLP and its paralogue MYB88 directly regulate transcription levels of the PIN3 and PIN7 genes, a regulation that in turn mediates auxin transport that contributes to the gravitropic responses of primary and lateral roots. Our results support a model in which FLP and MYB88 determines the temporal-spatial patterns of PIN3 and PIN7 transcription that are closely associated with their preferential functions during root responses to gravity

Methods

Results

Conclusion