title: Auxin Response Gene SlARF3 Plays Multiple Roles in Tomato Development and is Involved in the Formation of Epidermal Cells and Trichomes.
abstract: The auxin response factor (ARF) genes encode a large family of proteins involved in auxin signaling transduction. SlARF3, a member of the ARF gene family, encodes a protein containing two conserved domains, B3 and ARF, and lacking an Aux/IAA domain. Expression analysis showed that SlARF3 has a particularly high expression level in trichomes. In situ hybridization also detected the SlARF3 transcripts in epidermal pavement cells of leaves. The physiological function of SlARF3 was studied by using the RNA interference (RNAi) strategy. SlARF3-down-regulated plants exhibited decreased density of epidermal pavement cells and obviously reduced density of type I, V and VI trichomes of leaves, which indicates the important role of SlARF3 in the formation of trichomes and epidermal cells in tomato. The number of shoot xylem cells was also decreased in SlARF3-down-regulated lines. Furthermore, RNA-sequencing (RNA-Seq) analysis identified 51 differentially expressed genes (DEGs) belonging to 14 transcription factor (TF) families, such as MYB, bHLH, WD40 and C2H2 zinc finger. Twenty-seven DEGs were involved in the metabolism and signaling transduction of phytohormones, such as auxin, ethylene and gibberellin. These results indicated the important roles of the TFs and hormones in auxin-dependent transcriptional regulation of trichome formation in tomato. Taken together, our results demonstrate that SlARF3 plays an important role in the formation of epidermal cells and trichomes and reveal novel and specific functions for ARFs in tomato developmental processes.
authors.affiliation: Genetic Engineering Research Center, Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission, School of Life Science, Chongqing University, Chongging 400030, PR China These authors contributed equally to this work.
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Genetic Engineering Research Center, Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission, School of Life Science, Chongqing University, Chongging 400030, PR China These authors contributed equally to this work.
authors.forename: Fang
authors.initials: F
authors.lastname: Yan
authors.affiliation: Genetic Engineering Research Center, Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission, School of Life Science, Chongqing University, Chongging 400030, PR China.
authors.forename: Yuwei
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Genetic Engineering Research Center, Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission, School of Life Science, Chongqing University, Chongging 400030, PR China.
authors.forename: Yujin
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Genetic Engineering Research Center, Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission, School of Life Science, Chongqing University, Chongging 400030, PR China dengwei1977@cqu.edu.cn zhengguoli@cqu.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Deng
authors.affiliation: Genetic Engineering Research Center, Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission, School of Life Science, Chongqing University, Chongging 400030, PR China.
authors.forename: Zhengguo
authors.initials: Z
authors.lastname: Li
mesh_terms: D015536:Down-Regulation; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*; D015398:Signal Transduction; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D064201:Trichomes / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D052584:Xylem / Q000378:metabolism
chemical_list: D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins; D014157:Transcription Factors
keywords: ARF; Auxin; Down-regulation; Formation; Tomato; Trichome