Cryptocyanin, a copper-free hexameric protein in crab (Cancer magister) hemolymph, has been characterized and the amino acid sequence has been deduced from its cDNA. It is markedly similar in sequence, size, and structure to hemocyanin, the copper-containing oxygen-transport protein found in many arthropods. Cryptocyanin does not bind oxygen, however, and lacks three of the six highly conserved...

SYNOPSIS. The exoskeleton of crustaceans and insects is formed by cells of the hypodermis, but several hemolymph proteins contribute to the synthesis of the new exoskeleton. These hemolymph proteins share a surprising degree of sequence similarity and are members of the hemocyanin gene family. Copper-containing prophenoloxidases of crustaceans and insects are directly involved in cross-linking ...

The project was carried out to compare the performance of molted layers by aluminium oxide supplementation in cages and on litter floor system. Seventy two Single Comb White Leghorn commercial layers (60 weeks old) were divided into six experimental units of 12 layers each. These experimental units were randomly divided into two groups, each consisting of three experimental units, one group was...

 The influence of five pure diets of isonitrogenous and isoenergic with different ratios of Clupeidae fish oil (F) and soybean oil (S) on growth, molting and survival of narrow-clawed crayfish, Astacus leptodactylus, was evaluated during an 8-weeks trial. As soybean oil replaced with fish oil in each treatment, gently. Test diets were inclusive F0/S100, F30/S70, F50/S50, F70/S30 and F100/S0 fis...

The Drosophila miRNA-encoding gene bantam controls cell and tissue growth. A new study now reveals that a large part of its effects on growth could come from its inhibition of the production of the molting hormone ecdysone.

Molting and metamorphosis in insects are under the control of two hormones, the steroid ecdysone and the sesquiterpenoid juvenile hormone (JH) (Riddiford, 1994) [We use the term ‘ecdysone’ as a generic term to refer to the natural ecdysteroids that cause molting and metamorphosis, primarily α-ecdysone and its metabolite 20-hydroxyecdysone (Riddiford et al., 2001).] Ecdysone induces and coordina...

Persistent organic pollutants, including polychlorinated biphenyls (PCBs), are widely distributed and detectable far from anthropogenic sources. Northern elephant seals (Mirounga angustirostris) biannually travel thousands of kilometers to forage in coastal and open-ocean regions of the northeast Pacific Ocean and then return to land where they fast while breeding and molting. Our study examine...

Transglutaminases (E.C. 2.3.3.13) are a family of Ca(2+)-dependent enzymes that stabilize protein structure by catalyzing the formation of isopeptide bonds. A novel form of transglutaminase has been identified and characterized that seem to play an important role in growth, development, and molting in adult and larval stages of filarial nematodes. The aim of this study was to identify the ubiqu...

Nephila are known for the greatest degrees of sexual size dimorphism among orb weaving spiders (Araneoidea) and thus among terrestrial animals. However, a meaningful quantification of the dimorphism is lacking and the proximate developmental mechanisms of female gigantism are poorly understood, being attributed solely to female delayed maturation. Here we show that females in the giant wood spi...

Molting and metamorphosis are strictly regulated by steroid hormones known as ecdysteroids. It is now widely recognized that ecdysteroid biosynthesis (ecdysteroidogenesis) in the prothoracic gland (PG) is regulated by the tropic factor prothoracicotropic hormone (PTTH). However, the importance of PTTH in the induction of molting and metamorphosis remains unclear, and other mechanisms are though...