The role of specialized regions of insect rectal papillae in the regulation of water and ion uptake is well documented. Although the apparatus for active uptake of water or ions is located in various cell membranes, the absorbed molecules must first pass through the cuticle which lines the rectal epithelium. Most cuticle (e.g. abdominal) has been shown to be permeable only to molecules soluble ...

Altlhoughl cutimize(d tissue in some forlmi is the first harrier to the entrv of chemicals into plants, dlirect measurements of the permeability properties of cuticular membranes are limited aandl qualitative (1, 5 ). Froml clirect miieasuremleints oin isolated cuiticle Skoss (9 ) has reported that Eniglish ivy leaf cuticle is relativelv illmpermleable to w ater, aandl that lemloni leaf cuticle...

The development of the imaginal cuticle has been studied with particular emphasis on the microtrichia and the pupal moulting fluid. The microtrichia are formed from acidophil filaments of epidermal cytoplasm which remain as the cuticular pore canals after secretion of the endocuticle. Microtrichia at the base of the bristles are associated with nerves. The cuticle before emergence consists of a...

Cuticular proteins are one of the determinants of the physical properties of cuticle. A common consensus region (extended R&R Consensus) in these proteins binds to chitin, the other major component of cuticle. We previously predicted the preponderance of beta-pleated sheet in the consensus region and proposed its responsibility for the formation of helicoidal cuticle (Iconomidou et al., Insect ...

BACKGROUND The plant cuticle is an extracellular lipophilic biopolymer covering leaf and fruit surfaces. Its main function is the protection of land-living plants from uncontrolled water loss. In the past, the permeability of the cuticle to water and to non-ionic lipophilic molecules (pesticides, herbicides and other xenobiotics) was studied intensively, whereas cuticular penetration of polar i...

The plant cuticle is thought to be a critical evolutionary adaptation that allowed the first plants to colonize land, because of its key roles in regulating plant water status and providing protection from biotic and abiotic stresses. Much has been learned about cuticle composition and structure through genetic and biochemical studies of angiosperms, as well as underlying genetic pathways, but ...

Seed production in angiosperms requires tight coordination of the development of the embryo and the endosperm. The endosperm-specific transcription factor ZHOUPI has previously been shown to play a key role in this process, by regulating both endosperm breakdown and the formation of the embryonic cuticle. To what extent these processes are functionally linked is, however, unclear. In order to a...

The covered/naked caryopsis trait of barley is an important agronomic trait because it is directly linked to dietary use. The formation of covered/naked caryopsis is controlled by an NUD transcription factor, which is involved in pericarp cuticle development. However, the molecular mechanism underlying this trait remains so far largely unknown. In this study, comparative transcriptomes of grain...