title: Genome-wide identification and expression profiling analysis of the Aux/IAA gene family in Medicago truncatula during the early phase of Sinorhizobium meliloti infection.
abstract: BACKGROUND
  Auxin/indoleacetic acid (Aux/IAA) genes, coding a family of short-lived nuclear proteins, play key roles in wide variety of plant developmental processes, including root system regulation and responses to environmental stimulus. However, how they function in auxin signaling pathway and symbiosis with rhizobial in Medicago truncatula are largely unknown. The present study aims at gaining deeper insight on distinctive expression and function features of Aux/IAA family genes in Medicago truncatula during nodule formation.
  
  
  RESULTS
  Using the latest updated draft of the full Medicago truncatula genome, a comprehensive identification and analysis of IAA genes were performed. The data indicated that MtIAA family genes are distributed in all the M. truncatula chromosomes except chromosome 6. Most of MtIAA genes are responsive to exogenous auxin and express in tissues-specific manner. To understand the biological functions of MtIAA genes involved in nodule formation, quantitative real-time polymerase chain reaction (qRT-PCR) was used to test the expression profiling of MtIAA genes during the early phase of Sinorhizobium meliloti (S. meliloti) infection. The expression patterns of most MtIAA genes were down-regulated in roots and up-regulated in shoots by S. meliloti infection. The differences in expression responses between roots and shoots caused by S. meliloti infection were alleviated by 1-NOA application.
  
  
  CONCLUSIONS
  The genome-wide identification, evolution and expression pattern analysis of MtIAA genes were performed in this study. The data helps us to understand the roles of MtIAA-mediated auxin signaling in nodule formation during the early phase of S. meliloti infection.
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China.
authors.forename: Chenjia
authors.initials: C
authors.lastname: Shen
authors.affiliation: Henan Academy of Agricultural Sciences, Zhengzhou, China.
authors.forename: Runqing
authors.initials: R
authors.lastname: Yue
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Plant Pathology, Washington State University, Pullman, Washington, United States of America.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Sun
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China.
authors.forename: Luqin
authors.initials: L
authors.lastname: Xu
authors.affiliation: Henan Academy of Agricultural Sciences, Zhengzhou, China.
authors.forename: Shuanggui
authors.initials: S
authors.lastname: Tie
authors.affiliation: College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China.
authors.forename: Huizhong
authors.initials: H
authors.lastname: Wang
mesh_terms: D020816:Amino Acid Motifs; D002874:Chromosome Mapping; D016000:Cluster Analysis; D005091:Exons; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D055106:Genome-Wide Association Study; D007438:Introns; D046913:Medicago truncatula / Q000145:classification / Q000235:genetics* / Q000382:microbiology*; D005810:Multigene Family; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism; D056510:Position-Specific Scoring Matrices; D016962:Sinorhizobium meliloti
chemical_list: D009687:Nuclear Proteins; D010940:Plant Proteins