Silencing against the conserved NAC domain of the potato StNAC103 reveals new NAC candidates to repress the suberin associated waxes in phellem.

Both suberin and its associated waxes contribute to the formation of apoplastic barriers that protect plants from the environment. Some transcription factors have emerged as regulators of the suberization process. The potato StNAC103 gene was reported as a repressor of suberin polyester and suberin-associated waxes deposition because its RNAi-mediated downregulation (StNAC103-RNAi) over-accumulated suberin and associated waxes in the tuber phellem concomitantly with the induction of representative biosynthetic genes.

The Identification and Quantification of Suberin Monomers of Root and Tuber Periderm from Potato (Solanum tuberosum) as Fatty Acyl tert-Butyldimethylsilyl Derivatives.

Introduction: Protective plant lipophilic barriers such as suberin and cutin, with their associated waxes, are complex fatty acyl derived polyesters. Their precise chemical composition is valuable to understand the specific role of each compound to the physiological function of the barrier.

Objectives: To develop a method for the compositional analysis of suberin and associated waxes by gas chromatography (GC) coupled to ion trap-mass spectrometry (IT-MS) using N-(tert-butyldimethylsilyl)-N-methyl-trifluoroacetamide (MTBSTFA) as sylilating reagent, and apply it to compare the suberin of the root and tuber periderm of potato (Solanum tuberosum).

Silencing of the potato StNAC103 gene enhances the accumulation of suberin polyester and associated wax in tuber skin.

Suberin and wax deposited in the cork (phellem) layer of the periderm form the lipophilic barrier that protects mature plant organs. Periderm lipids have been widely studied for their protective function with regards to dehydration and for how they respond to environmental stresses and wounding. However, despite advances in the biosynthetic pathways of suberin and associated wax, little is known about the regulation of their deposition.