Amiloride-sensitive Na+ absorption is a well-described feature of numerous transporting epithelia in vertebrates. Yet, very little is known about this important physiological process regarding invertebrates. In the present paper, we compare vertebrate Na+ absorption mediated by the amiloride-sensitive epithelial Na+ channel (ENaC) and its invertebrate counterpart. We used the dorsal skin of the...

Peroxidase activity was assayed in crude extracts of integument, cotyledons and embryo axis of radish seeds, deteriorated under accelerated ageing conditions. Over five days of ageing, in which germination decreased from 100 to 52%, the enzyme activity in integument was higher than that in other seed parts, increasing in the first days of ageing and then decreasing sharply in extremely aged see...

Sepiapterin is the precursor of tetrahydrobiopterin, an important coenzyme of aromatic amino acid hydroxylases, the lack of which leads to a variety of physiological metabolic diseases or neurological syndromes in humans. Sepiapterin is a main pigment component in the integument of the lemon mutant of the silkworm, Bombyx mori (L.) (Lepidoptera: Bombycidae), and is present there in extremely hi...

Ovules are specialized reproductive organs that develop within the carpels of higher plants. In Arabidopsis, mutations in two genes, BELL1 (BEL1) and APETALA2 (AP2), disrupt ovule development. In Bel1 ovules, the inner integument fails to form, the outer integument develops abnormally, and the embryo sac arrests at a late stage of megagametogenesis. During later stages of ovule development, cel...

GLANDS of the skin or integument of birds are frequently assumed to be limited to the uropygeal glands (Pycraft, 1910; GrassY, 1950; and others). Nevertheless, if one includes with integument those areas that are histologically skin-like but form unions with mucous membranes or deeper structures, additional glands must be considered. One set of these little-known glands is that found in the int...

Avian species have a unique integument covered with feathers. Skin morphogenesis is a successive and complex process. To date, most studies have focused on a single developmental point or stage. Fewer studies have focused on whole transcriptomes based on the time-course of embryo integument development. To analyze the global changes in gene expression profiles, we sequenced the transcriptome of...

For decades, carotenoids have attracted attention for their roles as vitamin-A precursors, antioxidants, and immunostimulants, but we still understand very little about the metabolic processes that accompany these compounds. Animals like birds use carotenoids to color their feathers and bare parts to become sexually attractive. They commonly metabolically derive their body colorants from dietar...

In this study, we report findings from a microscopic analysis of the white rhinoceros (Ceratotherium simum) integumentary ultrastructure. Skin samples from the cheek, shoulder, flank and rump were taken from a 46-year-old female southern white rhinoceros and examined using H&E and elastic histological stains. The epidermis was thickest in the flank (1.003 mm) followed by the rump, cheek and sho...

The insects and microarthropods that vary seasonally in susceptibility to cross-cuticular inoculation by external ice (inoculative freezing) represent a phylogenetically diverse group; however, few studies have explored possible mechanisms experimentally. This study documents seasonally variable inoculative freezing resistance in Dendroides canadensis beetle larvae and combines immunofluorescen...