Genome-wide identification of AUX/IAA in radish and functional characterization of RsIAA33 gene during taproot thickening

Yang Xie; Jiali Ying; Mingjia Tang; Yan Wang; Liang Xu; Meiyan Liu; Liwang Liu

doi:10.1016/j.gene.2021.145782

Genome-wide identification of AUX/IAA in radish and functional characterization of RsIAA33 gene during taproot thickening

Gene. 2021 Aug 30:795:145782. doi: 10.1016/j.gene.2021.145782. Epub 2021 Jun 17.

Authors

Yang Xie¹, Jiali Ying², Mingjia Tang², Yan Wang², Liang Xu³, Meiyan Liu⁴, Liwang Liu⁵

Affiliations

¹ National Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOA, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, People's Republic of China; Hebei Key Laboratory of Horticultural Germplasm Excavation and Innovative Utilization, College of Horticulture Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China.
² National Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOA, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
³ National Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOA, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, People's Republic of China. Electronic address: nauxuliang@njau.edu.cn.
⁴ Hebei Key Laboratory of Horticultural Germplasm Excavation and Innovative Utilization, College of Horticulture Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China.
⁵ National Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOA, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, People's Republic of China. Electronic address: nauliulw@njau.edu.cn.

PMID: 34146634
DOI: 10.1016/j.gene.2021.145782

Abstract

Auxin/indole-3-acetic acid (Aux/IAA) genes encode short lived nuclear proteins that cooperated with auxin or auxin response factor (ARF), which are involved in plant growth and developmental processes. However, it's still ambiguous how the Aux/IAA genes regulate the process governing taproot thickening in radish. Herein, 65 Aux/IAA genes were identified from the radish genome. Gene duplication analysis showed that two pairs of tandem duplication and 17 (27%) segmental duplication events were identified among Aux/IAA family genes in radish. Transcriptomic analysis revealed that most of Aux/IAA genes (52/65) exhibited differential expression pattern in different root tissues, and six root-specific genes were highly expressed in root cortex, cambium, xylem, and root tip in radish. RT-qPCR analysis showed that the expression level of RsIAA33 was the highest at cortex splitting stage (CSS), and early expanding stage (ES). Furthermore, amiRNA-mediated gene silencing of RsIAA33 indicated that it could inhibit the reproductive growth, thus promoting taproot thickening and development. These results would provide valuable information for elucidating the molecular function of Aux/IAA genes involved in taproot thickening in radish.

Keywords: Aux/IAA genes; Gene expression; Radish; Taproot thickening.

MeSH terms

Gene Duplication
Gene Expression Profiling
Gene Expression Regulation, Plant*
Genes, Plant*
Indoleacetic Acids / immunology*
Indoleacetic Acids / metabolism
Multigene Family
Plant Roots / genetics*
Plant Roots / growth & development*
Raphanus / genetics*
Raphanus / growth & development*
Real-Time Polymerase Chain Reaction

Substances

Indoleacetic Acids
indoleacetic acid