Aux/IAA Gene Family in Plants: Molecular Structure, Regulation, and Function.

Jie Luo,Jing-Jing Zhou,Jin-Zhi Zhang

doi:10.3390/ijms19010259

Jie Luo, Jing-Jing Zhou + Show 1 more

Open Access

https://doi.org/10.3390/ijms19010259

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Abstract

Auxin plays a crucial role in the diverse cellular and developmental responses of plants across their lifespan. Plants can quickly sense and respond to changes in auxin levels, and these responses involve several major classes of auxin-responsive genes, including the Auxin/Indole-3-Acetic Acid (Aux/IAA) family, the auxin response factor (ARF) family, small auxin upregulated RNA (SAUR), and the auxin-responsive Gretchen Hagen3 (GH3) family. Aux/IAA proteins are short-lived nuclear proteins comprising several highly conserved domains that are encoded by the auxin early response gene family. These proteins have specific domains that interact with ARFs and inhibit the transcription of genes activated by ARFs. Molecular studies have revealed that Aux/IAA family members can form diverse dimers with ARFs to regulate genes in various ways. Functional analyses of Aux/IAA family members have indicated that they have various roles in plant development, such as root development, shoot growth, and fruit ripening. In this review, recently discovered details regarding the molecular characteristics, regulation, and protein–protein interactions of the Aux/IAA proteins are discussed. These details provide new insights into the molecular basis of the Aux/IAA protein functions in plant developmental processes.

Highlights

In plants, many developmental processes are finely tuned by auxin, such as vascular tissue formation, adventitious root initiation, tropistic responses, apical dominance, and flower and fruit development
Auxin/Indole-3-Acetic Acid (Aux/IAA) family members have been identified as short-lived nuclear proteins that play a crucial role in repressing the expression levels of genes activated by auxin response factor (ARF) [7,8]
These advances reveal that Aux/IAA genes act as hub factors that regulate gene expression in auxin signaling transduction, and understanding of their molecular functions and regulatory machinery in plant growth and development has been greatly enhanced

Summary

Introduction

Many developmental processes are finely tuned by auxin, such as vascular tissue formation, adventitious root initiation, tropistic responses, apical dominance, and flower and fruit development. Aux/IAA family members have been identified as short-lived nuclear proteins that play a crucial role in repressing the expression levels of genes activated by ARFs [7,8]. The spatial–temporal dynamic change in auxin levels can be finely transformed into gene reprogramming signaling, thereby regulating the processes of plant growth and development in a precise manner.

Results

Conclusion