Cuticle thickness affects dynamics of volatile emission from petunia flowers

To protect and emit beauty

“…1a), and cellular formation of G4s has been demonstrated to play key roles in transcription, genomic and epigenetic instability, aging processes, and cancer development 2 . As the diverse functions of G4s are often governed by their interaction with G4-binding proteins, studies in recent years have been focused on identifying G4-binding proteins 2,3 ; however, their biochemical and mechanistic roles are still not well characterized. In this issue, Li et al 4 identified Yin Yang 1 (YY1) as a novel G4-binding protein that directly interacts with the G4 structure and revealed that such YY1-G4 interaction contributed to long-range DNA looping and regulated the expression of proximal and distal genes (Fig.…”

“…To interact with their surrounding ecosystem, plant-derived VOCs must cross numerous biological interfaces to get from their intracellular site of biosynthesis to the atmosphere. In this issue of Nature Chemical Biology, Liao et al 3 reveal that the waxy cuticle of petunia flowers not only provides a major resistance to VOC emission, but also plays surprising and important roles as both a reservoir of the VOC scent compounds and a vital component of the emission pathway (Fig. 1).…”

“…Liao et al 3 tested the hypothesized resistance imposed by the cuticle using chemical and reverse-genetic approaches in hybrid petunia. Work with genetic mutants of ABC transporters in the model plant Arabidopsis thaliana had previously established that ABC transporters (AtABCG11 and AtABCG12) are required for export of lipids of the cuticle 6 .…”

“…Work with genetic mutants of ABC transporters in the model plant Arabidopsis thaliana had previously established that ABC transporters (AtABCG11 and AtABCG12) are required for export of lipids of the cuticle 6 . The work from Liao et al 3 identifies the petunia homologs responsible for cuticle secretion: PhABCG11 and PhABCG12. When transgenic petunia flowers were engineered to knock down these transporters using RNA interference, the thickness and chemical composition of the cuticle of the petunia flowers could be manipulated.…”

“…Thus, the capacity of the plant cuticle to act as a sink and barrier to VOC emission appears to depend on the physicochemical properties of the compound in question. Liao et al 3 have shown that although the cuticle does impart substantial resistance to VOC emission, it also plays seemingly paradoxical roles in maintaining high VOCs produced within the conical petal cells made inside the cell are exported through the plasma membrane and the cell wall to reach the cuticle. The cuticle is a major resistance barrier to emission of low vapor pressure metabolites (blue arrows and stars), whereas emission of high vapor pressure metabolites (red arrows and circles) is unimpeded by the cuticle.…”