E-MEXP-3989 - A novel dominant glossy mutation causes suppression of wax biosynthesis pathway and deficiency on cuticular wax in Brassica napus
Released on 7 December 2013, last updated on 3 June 2014
The present study reports the genetic and biochemical characterization of a dominant glossy mutant allele (BnaA. GL) in B. napus that results in a glossy phenotype. Results from transmission electron microscopy and scanning electron microscopy revealed the GL mutant exhibits reduced deposition of the cuticle layer, which was confirmed by a cuticular wax analysis. The wax compositional analysis revealed an increase in aldehydes but a severe decrease in alkanes, ketones and secondary alcohols. Genetic mapping narrowed the BnaA. GL gene to the end of A9 chromosome, where a gene homologous to ECERIFERUM1 (CER1) in Arabidopsis locates.
Then, we conducted a microarray analysis to find the differentially expressed genes between normal phenotype and glossy plants. Two comparisons were performed: wild type parent VS. the GL parent, and the bulked normal phenotype DH lines VS. the bulked glossy DH lines. The DH lines are generated from F1 plants of two parents, and RNA samples from three DH lines were combined to make a bulked sample for each phenotype.
Although no discernible mutation was apparent in the B. napus gene, this cDNA microarray chip assay revealed coordinated down regulation of genes encoding enzymes of the cuticular wax biosynthetic in the glossy mutant with BnCER1 being one of the most severely suppressed genes.
transcription profiling by array, co-expression, genotype design, replicate design
A novel dominant glossy mutation causes suppression of wax biosynthesis pathway and deficiency on cuticular wax in Brassica napus.