Microarray-detected changes in gene expression in gills of green crabs (Carcinus maenas) upon dilution of environmental salinity.

The interaction between environmental salinity and gene expression was studied in gills of the euryhaline green shore crab Carcinus maenas. A 4462-feature oligonucleotide microarray was used to analyze changes in transcript abundance in posterior ion-transporting gills at 8 time periods following transfer of animals from 32 to 10 or 15 ppt salinity. Transcripts encoding Na(+)/K(+)-ATPase α-subunit and cytoplasmic carbonic anhydrase were upregulated with significant changes between 6 and 24h post-transfer.

Recent advances in crustacean genomics.

Crustaceans are a diverse and ancient group of arthropods that have long been studied as interesting model systems in biology, especially for understanding animal evolution and physiology and for environmentally relevant studies. Like many model systems, advances in DNA-sequencing methodologies have led to a large amount of genomics-related projects. The purpose of this article is to highlight the genome projects and functional genomics (transcriptomics) projects that are currently underway in crustacean biology.

Hemocyanins and the immune response: defense against the dark arts.

The innate immune response is a conserved trait shared by invertebrates and vertebrates. In crustaceans, circulating hemocytes play significant roles in the immune response, including the release of prophenoloxidases. Activated phenoloxidase (tyrosinase) participates in encapsulation and melanization of foreign organisms as well as sclerotization of the new exoskeleton after wound-repair or molting.

Crustacean hemocyanin gene family and microarray studies of expression change during eco-physiological stress.

Proteins in the arthropod hemocyanin gene family are involved in major physiological processes, including aerobic respiration, the innate immune response, and molting. Members of this family, hemocyanin, cryptocyanin, and phenoloxidase, are multisubunit molecules that assemble into hexamers and higher aggregates. The hemocyanin hexamers show species-specific subunit heterogeneity.

Functional and phylogenetic analyses of phenoloxidases from brachyuran (Cancer magister) and branchiopod (Artemia franciscana, Triops longicaudatus) crustaceans.

Arthropod phenoloxidases catalyze the melanization and sclerotization of the new postmolt exoskeleton, and they function in the immune response. Hemocyanin, phylogenetically related to phenoloxidase, can function as a phenoloxidase under certain conditions. We investigated the relative contributions of hemocyte phenoloxidase and hemocyanin in the brachyuran crab Cancer magister, using the physiological ratio at which they occur in the hemolymph, and found that hemocyte phenoloxidase has higher activity.