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=<p>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 <italic>ARF</italic> 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 homologs of ARFs. A total of 19 nonredundant <italic>ARF</italic> genes (<italic>CiARF</italic>) were found and validated from the sweet orange. A comprehensive overview of the <italic>CiARF</italic>s was undertaken, including the gene structures, phylogenetic analysis, chromosome locations, conserved motifs of proteins, and <italic>cis</italic>-elements in promoters of CiARF. Furthermore, expression profiling using real-time PCR revealed many <italic>CiARF</italic> 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 (IAA) and N-1-napthylphthalamic acid (NPA) treatment experiments revealed differential up-regulation and down-regulation, respectively, of the 19 citrus <italic>ARF</italic> genes in the callus of sweet orange. Our comprehensive analysis of ARF genes further elucidates the roles of <italic>CiARF</italic> family members during citrus growth and development process.</p>