OsIAAGLU,OsIAGT1

| Categories genes  | Tags flower  iaa  tiller  leaf  gravitropic response  root  shoot  panicle  architecture  homeostasis  height  plant height  IAA  plant architecture  shoot architecture  growth  auxin  development  root length  plant stature  seed  ABA  abscisic acid  breeding  ABA 
  • Information
  • Publication

  • Genbank accession number

  • Key message
    • The OsIAGLU gene driven by the Cauliflower Mosaic Virus 35S promoter was transformed into a rice cultivar to generate transgenic rice plants constitutively over-expressing this gene
    • To decrease IAA levels, we selected the rice IAA-glucose synthase gene (OsIAGLU) from the rice genome database based on high sequence homology with IAA-glucose synthase from maize (ZmIAGLU), which is known to generate IAAglucose conjugate from free IAA
    • Tiller formation in rice is altered by overexpression of OsIAGLU gene encoding an IAA-conjugating enzyme or exogenous treatment of free IAA
    • The number of tillers and leaf angle was significantly increased with a concomitant decrease in plant height and panicle length in the transgenic rice lines overexpressing OsIAAGLU compared to the wild-type (WT) plants
    • Furthermore, overexpression of OsIAAGLU resulted in reduced sensitivity to IAA/NAA and altered gravitropic response of the roots in the transgenic plants
    • Overexpression of OsIAAGLU in rice resulted in altered rice shoot architecture and root gravitropism
    • These results support that OsIAAGLU could play a regulatory role in IAA homeostasis and rice architecture
    • OsIAAGLU could catalyze the reaction of IAA with glucose to generate IAA-glucose
    • Expression of OsIAAGLU could be induced by IAA and NAA
    • Overexpression of OsIAAGLU reveals a role for IAA-glucose conjugation in modulating rice plant architecture.
    • Consistently, ectopic expression of OsIAGT1 leads to declined endogenous IAA content, as well as upregulated auxin synthesis genes and reduced expression of auxin-responsive genes, which likely leads to the reduced plant stature and root length in OsIAGT1 overexpression lines
    • Our result indicated that OsIAGT1 plays an important role in mediating auxin homeostasis by catalyzing auxin glucosylation, and by which OsIAGT1 regulates growth and development in rice
    • In vitro enzymatic analysis showed that recombinant OsIAGT1 was capable of catalyzing glucosylation of IAA, IBA and other auxin analogs, and that OsIAGT1 is quite tolerant to a broad range of reaction conditions with peak activity at 30 㧳 and pH<U+2009>8
    • Further study indicated that expression of OsIAGT1 can be upregulated by auxin in rice, and with OsIAGT1 overexpressing lines we confirmed that OsIAGT1 is indeed able to glucosylate IAA in vivo
    • Indole-3-acetate beta-glucosyltransferase OsIAGLU regulates seed vigor through mediating crosstalk between auxin and abscisic acid in rice.
    • In this study, indole-3-acetate beta-glucosyltransferase OsIAGLU was cloned in rice, and its roles on seed vigor were mainly investigated
    • Disruption of OsIAGLU resulted in low seed vigor in rice
    • Transcriptome analysis revealed that the IAA- and ABA-related genes were involved in the OsIAGLU regulation of seed vigor in rice
    • When treated with exogenous IAA and ABA, the osiaglu mutants and WT plants showed sensitivity to ABA while not IAA, but the exogenous IAA amplified ABA-induced reduction of seed vigor in rice
    • The regulation of seed vigor by OsIAGLU might be through modulating IAA and ABA levels to alert OsABIs expression in germinating seeds in rice
    • Based on analysis of single-nucleotide polymorphism data of rice accessions, two haplotypes of OsIAGLU that positively correlated with seed vigor were identified in indica accessions
    • This study provides important insights into the roles of OsIAGLU on seed vigor and facilitates the practical use of OsIAGLU in rice breeding
    • The higher levels of free IAA and ABA were identified in germinating seeds of osiaglu mutants compared to wide-type (WT) plants
    • The continuously higher expressions of ABA INSENSITIVE 3 (OsABI3) and OsABI5 occurred in germinating seeds of osiaglu mutants compared to WT plants
    • Quantitative RT-PCR analysis showed that the expressions of OsIAGLU were relatively higher in the late developing and the early germinating seeds and were significantly induced by indole-3-acetic acid (IAA) and abscisic acid (ABA)
  • Connection

Prev     Next