Brassinosteroids rescue the deficiency of CYP90, a cytochrome P450, controlling cell elongation and de-etiolation in Arabidopsis

Cell. 1996 Apr 19;85(2):171-82. doi: 10.1016/s0092-8674(00)81094-6.


The cpd mutation localized by T-DNA tagging on Arabidopsis chromosome 5-14.3 inhibits cell elongation controlled by the ecdysone-like brassinosteroid hormone brassinolide. The cpd mutant displays de-etiolation and derepression of light-induced genes in the dark, as well as dwarfism, male sterility, and activation of stress-regulated genes in the light. The CPD gene encodes a cytochrome P450 (CYP90) sharing homologous domains with steroid hydroxylases. The phenotype of the cpd mutant is restored to wild type both by feeding with C23-hydroxylated brassinolide precursors and by ectopic overexpression of the CPD cDNA. Brassinosteroids also compensate for different cell elongation defects of Arabidopsis det, cop, fus, and axr2 mutants, indicating that these steroids play an essential role in the regulation of plant development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis Proteins*
  • Brassinosteroids
  • Cell Size / drug effects
  • Cell Size / genetics
  • Cholestanols*
  • Chromosome Mapping
  • Cytochrome P-450 Enzyme System / deficiency*
  • Cytochrome P-450 Enzyme System / genetics
  • Gene Expression Regulation, Plant / genetics
  • Genes, Plant / genetics
  • Genetic Complementation Test
  • Molecular Sequence Data
  • Mutation / genetics
  • Phenotype
  • Plant Growth Regulators*
  • Plant Proteins / genetics*
  • Sequence Homology, Amino Acid
  • Steroid Hydroxylases / deficiency*
  • Steroid Hydroxylases / genetics
  • Steroids, Heterocyclic*


  • Arabidopsis Proteins
  • Brassinosteroids
  • Cholestanols
  • Plant Growth Regulators
  • Plant Proteins
  • Steroids, Heterocyclic
  • Cytochrome P-450 Enzyme System
  • CPD protein, Arabidopsis
  • Steroid Hydroxylases
  • brassinolide

Associated data

  • GENBANK/X87367
  • GENBANK/X87368