AUTHOR=Li Si-Bei , OuYang Wei-Zhi , Hou Xiao-Jin , Xie Liang-Liang , Hu Chun-Gen , Zhang Jin-Zhi 

TITLE=Genome-wide identification, isolation and expression analysis of auxin response factor (ARF) gene family in sweet orange (Citrus sinensis)

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 6 - 2015

YEAR=2015

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2015.00119

DOI=10.3389/fpls.2015.00119

ISSN=1664-462X

ABSTRACT=Auxin response factors (ARFs) are an important family of proteins in auxin-mediated response, with key roles in various physiological and biochemical processes. To date, a genome-wide overview of the ARF gene family in citrus was not available. A systematic analysis of this gene family in citrus was begun by carrying out a genome-wide search for the homologues of auxin response genes. A total of 19 non-redundant ARF genes (CiARF) were identified and validated from the sweet orange genome. A comprehensive overview of the CiARF gene family was undertaken, including the gene structures, phylogeny, chromosome locations, conserved motifs, and cis-elements in promoter sequences. Furthermore, expression profiling using real-time PCR revealed many CiARF genes, albeit with different patterns depending on types of tissues and/or developmental stages. Comprehensive expression analysis of these genes was also performed under two hormone treatments using real-time PCR. Indole-3-acetic acid and N-1-napthylphthalamic acid treatment experiments revealed differential up-regulation and down-regulation, respectively, of the 19 citrus ARF genes in the callus of sweet orange. Our comprehensive analysis of ARF genes further elucidates the roles of CiARF family members in citrus growth and development.