The maize (Zea mays L.) AUXIN/INDOLE-3-ACETIC ACID gene family: phylogeny, synteny, and unique root-type and tissue-specific expression patterns during development.
The plant hormone auxin plays a key role in the coordination of many aspects of growth and development. AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) genes encode instable primary auxin responsive regulators of plant development that display a protein structure with four characteristic domains. In the present study, a comprehensive analysis of the 34 members of the maize Aux/IAA gene family was performed. Phylogenetic reconstructions revealed two classes of Aux/IAA proteins that can be distinguished by alterations in their domain III. Seven pairs of paralogous maize Aux/IAA proteins were discovered. Comprehensive root-type and tissue-specific expression profiling revealed unique expression patterns of the diverse members of the gene family. Remarkably, five of seven pairs of paralogous genes displayed highly correlated expression patterns in roots. All but one (ZmIAA23) tested maize Aux/IAA genes were auxin inducible, displaying two types of auxin induction within three hours of treatment. Moreover, 51 of 55 (93%) differential Aux/IAA expression patterns between different root-types followed the expression tendency: crown roots > seminal roots > primary roots > lateral roots. This pattern might imply root-type-specific regulation of Aux/IAA transcript abundance. In summary, the detailed analysis of the maize Aux/IAA gene family provides novel insights in the evolution and developmental regulation and thus the function of these genes in different root-types and tissues.
Crop Functional Genomics, Institute of Crop Science and Resource Conservation, Rheinische-Friedrich-Wilhelms Universität, Bonn, Germany.
Yvonne
Y
Ludwig
Yanxiang
Y
Zhang
Frank
F
Hochholdinger
D000595:Amino Acid Sequence; D032461:Chromosomes, Plant / Q000235:genetics; D004268:DNA-Binding Proteins / Q000145:classification / Q000235:genetics*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007700:Kinetics; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D009280:Naphthaleneacetic Acids / Q000494:pharmacology; D009687:Nuclear Proteins / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D010940:Plant Proteins / Q000145:classification / Q000235:genetics*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D026801:Synteny; D013997:Time Factors; D003313:Zea mays / Q000235:genetics* / Q000254:growth & development
D004268:DNA-Binding Proteins; C109031:IAA1 protein, plant; D009280:Naphthaleneacetic Acids; D009687:Nuclear Proteins; D010940:Plant Proteins; C034182:1-naphthaleneacetic acid