Disease relevance of DWF1

• A null mutation in the tomato Dwarf (CYP85A1) gene, extreme dwarf (d(x)), causes severe dwarfism due to brassinosteroid deficiency, but the d(x) mutant still produces fruits [1].
• Unexpectedly, this group of known and predicted FAD-dependent oxidases includes the product of the DIMINUTO gene, which is involved in Arabidopsis development, and its homologues from man and Mycobacterium leprae [2].

High impact information on DWF1

• Overproduction and repression of Dim/dwf1 resulted in contrasting phenotypes, with repressors mimicking the brd2 phenotype and overproducers having large stature with increased numbers of flowers and seeds [3].
• Feeding experiments using deuterium-labeled 24-methylenecholesterol and 24-methyldesmosterol confirmed that DIM/DWF1 is involved in both the isomerization and reduction of the Delta24(28) bond [4].
• Transient expression of a green fluorescent protein-DIM/DWF1 fusion protein and biochemical experiments showed that DIM/DWF1 is an integral membrane protein that most probably is associated with the endoplasmic reticulum [4].
• The Arabidopsis DIMINUTO/DWARF1 gene encodes a protein involved in steroid synthesis [4].
• dwarf and delayed-flowering 1, a novel Arabidopsis mutant deficient in gibberellin biosynthesis because of overexpression of a putative AP2 transcription factor [5].

Biological context of DWF1

• Molecular genetic analysis using site-directed and deletion mutants revealed that loss of calmodulin binding completely abolished the function of DWF1 in planta, whereas partial loss of calmodulin binding resulted in a partial dwarf phenotype in complementation studies [6].
• Furthermore, the deduced amino acid sequence of DWF1 shows significant similarity to a flavin adenine dinucleotide-binding domain conserved in various oxidoreductases, suggesting an enzymatic role for DWF1 [7].
• Our results indicate that the AtBR6ox gene and the tomato Dwarf gene encode steroid-6-oxidases and that these enzymes have a broad substrate specificity [8].

Associations of DWF1 with chemical compounds

• Arabidopsis DWARF1 (DWF1) is responsible for an early step in brassinosteroid biosynthesis that converts 24-methylenecholesterol to campesterol [6].
• In support of this, 7 of 10 dwf1 mutations directly affected the flavin adenine dinucleotide-binding domain [7].
• The tomato (Lycopersicon esculentum) Dwarf gene encodes a cytochrome P450 that has been shown to catalyze the C-6 oxidation of 6-deoxocastasterone to castasterone [8].

Other interactions of DWF1

• In contrast, the expression of genes related to cell elongation, such as DWF1, SAUR, AQP, AGP15, DET3 and XET-1, was enhanced in leaves of the transgenic plants [9].

References