Ectopic expression of a stress-inducible glycosyltransferase from saffron enhances salt and oxidative stress tolerance in Arabidopsis while alters anchor root formation

Plant Sci. 2015 May:234:60-73. doi: 10.1016/j.plantsci.2015.02.004. Epub 2015 Feb 18.

Abstract

Glycosyltransferases play diverse roles in cellular metabolism by modifying the activities of regulatory metabolites. Three stress-regulated UDP-glucosyltransferase-encoding genes have been isolated from the stigmas of saffron, UGT85U1, UGT85U2 and UGT85V1, which belong to the UGT85 family that includes members associated with stress responses and cell cycle regulation. Arabidopsis constitutively expressing UGT85U1 exhibited and increased anchor root development. No differences were observed in the timing of root emergence, in leaf, stem and flower morphology or flowering time. However, salt and oxidative stress tolerance was enhanced in these plants. Levels of glycosylated compounds were measured in these plants and showed changes in the composition of several indole-derivatives. Moreover, auxin levels in the roots were higher compared to wild type. The expression of several key genes related to root development and auxin homeostasis, including CDKB2.1, CDKB2.2, PIN2, 3 and 4; TIR1, SHR, and CYCD6, were differentially regulated with an increase of expression level of SHR, CYCD6, CDKB2.1 and PIN2. The obtained results showed that UGT85U1 takes part in root growth regulation via auxin signal alteration and the modified expression of cell cycle-related genes, resulting in significantly improved survival during oxidative and salt stress treatments.

Keywords: Abiotic stress; Anchor root development; Auxin; Glucosyltransferases; Saffron; Stigmas.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / enzymology
  • Arabidopsis / genetics
  • Arabidopsis / physiology*
  • Crocus / enzymology*
  • Crocus / genetics
  • Ectopic Gene Expression
  • Flowers / enzymology
  • Flowers / genetics
  • Flowers / physiology
  • Gene Expression Regulation, Plant*
  • Glycosyltransferases / genetics*
  • Glycosyltransferases / metabolism
  • Indoleacetic Acids / metabolism*
  • Oxidation-Reduction
  • Oxidative Stress
  • Phenotype
  • Plant Growth Regulators / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plant Roots / enzymology
  • Plant Roots / genetics
  • Plant Roots / physiology
  • Plants, Genetically Modified
  • Salt Tolerance
  • Stress, Physiological

Substances

  • Indoleacetic Acids
  • Plant Growth Regulators
  • Plant Proteins
  • Glycosyltransferases