Micromorphological and Chemical Characterization of Drimys winteri Leaf Surfaces: The Secondary Alcohols Forming Epicuticular Wax Crystals Are Accompanied by Alkanediol, Alkanetriol and Ketol Derivatives.

The cuticle is a hydrophobic coating of most aerial plant surfaces crucial for limiting non-stomatal water loss. Plant cuticles consist of the lipid polyester cutin and associated waxes with compositions varying widely between plant species and organs. Here, we aimed to provide a comparative analysis of the dark-glossy adaxial and pale-glaucous abaxial sides of Drimys winteri (Winteraceae) leaves.

Characterization of the closely related Arabidopsis thaliana β-ketoacyl-CoA synthases KCS3, KCS12 and KCS19.

The cuticle, consisting of cuticular wax and cutin, is a lipid membrane that seals the plant surface against environmental stress. β-Ketoacyl-CoA synthases (KCSs) are condensing enzymes catalyzing crucial reactions elongating hydrocarbon chains into precursors for various cuticular wax components. Although many KCS genes were well characterized in various species, the functions of the closely related Arabidopsis KCS3, KCS12, KCS19 enzymes remained unclear.

Biosynthesis of barley wax β-diketones: a type-III polyketide synthase condensing two fatty acyl units.

The surface coatings of cereal plants are dominated by waxy β-diketones crucial for drought resistance and, therefore, grain yield. Here, barley (Hordeum vulgare) wax analyses reveal β-diketone and associated 2-alkanol ester profiles suggesting a common C 3-ketoacid precursor. Isotope analysis further shows that the major (C) diketone is synthesized from two plastidial C acyl units.

Empty pericarp7 encodes a mitochondrial E-subgroup pentatricopeptide repeat protein that is required for ccmFN editing, mitochondrial function and seed development in maize.

RNA editing, converting cytidines (C) to uridines (U) at specific sites in the transcripts of mitochondria and plastids, plays a critical role in organelle gene expression in land plants. Recently pentatricopeptide repeat (PPR) proteins were identified as site-specific recognition factors for RNA editing. In this study, we characterized an empty pericarp7 mutant (emp7) in Zea mays (maize), which confers an embryo-lethal phenotype.