Planta

, Volume 235, Issue 3, pp 485–498

DIMINUTO 1 affects the lignin profile and secondary cell wall formation in Arabidopsis

  • Zakir Hossain
  • Brian McGarvey
  • Lisa Amyot
  • Margaret Gruber
  • Jinwook Jung
  • Abdelali Hannoufa
Original Article

DOI: 10.1007/s00425-011-1519-4

Cite this article as:
Hossain, Z., McGarvey, B., Amyot, L. et al. Planta (2012) 235: 485. doi:10.1007/s00425-011-1519-4

Abstract

Brassinosteroids (BRs) play a crucial role in plant growth and development and DIMINUTO 1 (DIM1), a protein involved in BR biosynthesis, was previously identified as a cell elongation factor in Arabidopsis thaliana. Through promoter expression analysis, we showed that DIM1 was expressed in most of the tissue types in seedlings and sectioning of the inflorescence stem revealed that DIM1 predominantly localizes to the xylem vessels and in the interfascicular cambium. To investigate the role of DIM1 in cell wall formation, we generated loss-of-function and gain-of-function mutants. Disruption of the gene function caused a dwarf phenotype with up to 38 and 23% reductions in total lignin and cellulose, respectively. Metabolite analysis revealed a significant reduction in the levels of fructose, glucose and sucrose in the loss-of-function mutant compared to the wild type control. The loss-of-function mutant also had a lower S/G lignin monomer ratio relative to wild type, but no changes were detected in the gain-of-function mutant. Phloroglucinol and toluidine blue staining showed a size reduction of the vascular apparatus with smaller and disintegrated xylem vessels in the inflorescence stem of the loss-of-function mutant. Taken together, these data indicate a role for DIM1 in secondary cell wall formation. Moreover, this study demonstrated the potential role of BR hormones in modulating cell wall structure and composition.

Keywords

BrassinosteroidCelluloseDIMINUTO 1LigninVascular elements

Abbreviations

BR

Brassinosteroid

CesA

Cellulose synthase

CWR

Cell wall residue

DIM1

DIMINUTO 1

GUS

β-Glucuronidase

MS

Murashige and Skoog

qPCR

Quantitative real-time PCR

RNAi

RNA interference

TGA

Thioglycolic acid

Supplementary material

425_2011_1519_MOESM1_ESM.doc (86 kb)
Supplementary material 1 (DOC 86 kb)

Copyright information

© Her Majesty the Queen in Right of Canada as represented by Agriculture and Agri-Food Canada 2011

Authors and Affiliations

  • Zakir Hossain
    • 1
  • Brian McGarvey
    • 1
  • Lisa Amyot
    • 1
  • Margaret Gruber
    • 2
  • Jinwook Jung
    • 1
    • 3
  • Abdelali Hannoufa
    • 1
  1. 1.Agriculture and Agri-Food CanadaLondonCanada
  2. 2.Agriculture and Agri-Food CanadaSaskatoonCanada
  3. 3.Bayer CropScience LtdSeoulKorea