Calcium signaling and regulation of ecdysteroidogenesis in crustacean Y-organs.

Crustacean Y-organs secrete ecdysteroid molting hormones. Ecdysteroids are released in increased amount during premolt, circulate in hemolymph, and stimulate the events in target cells that lead to molting. During much of the molting cycle, ecdysteroid production is suppressed by molt-inhibiting hormone (MIH), a peptide neurohormone produced in the eyestalks.

Effect of a chemical dispersant (Corexit 9500A) on the structure and ion transport function of blue crab (Callinectes sapidus) gills.

Chemical dispersants are commercially available mixtures of surfactants and solvents that have become important tools in the remediation of spilled oil. Given the importance of oil to the world economy, the recurring nature of spills, and the prevalence of dispersant use in remediation, there is a critical need to understand potential toxic impacts of dispersants on invertebrate and vertebrate animals. Blue crabs (Callinectes sapidus) play ecologically important roles in the environments they inhabit and support economically important fisheries along the Atlantic Coast and in the Gulf of Mexico.

De novo transcriptome assembly and functional annotation for Y-organs of the blue crab (Callinectes sapidus), and analysis of differentially expressed genes during pre-molt.

Blue crabs (Callinectes sapidus) undergo incremental growth involving the shedding (molting) of the old exoskeleton, and subsequent expansion and re-calcification of the newly synthesized one. The cellular events that lead to molting are triggered by steroid hormones termed ecdysteroids released from Y-organs, paired endocrine glands located in the anterior cephalothorax. The regulatory pathways leading to increased synthesis and release of ecdysteroids are not fully understood, and no transcriptome has yet been published for blue crab Y-organs.

Sarco/endoplasmic reticulum Ca ATPase (SERCA) transcript abundance in Y-organs and ecdysteroid titer in hemolymph during a molting cycle of the Blue Crab, Callinectes sapidus.

Crustacean growth is characterized by molting, whereby the old exoskeleton is shed and replaced by a new and larger version. The cellular events that lead to molting are driven by steroid hormones (ecdysteroids) secreted by paired endocrine glands (Y-organs). Between molts, ecdysteroid production is suppressed by a polypeptide molt-inhibiting hormone (MIH) released from neurosecretory cells in the eyestalks.

Molecular cloning and characterization of a sarco/endoplasmic reticulum Ca ATPase (SERCA) from Y-organs of the blue crab (Callinectes sapidus).

Existing data indicate that a Ca signal stimulates ecdysteroid hormone production by crustacean molting glands (Y-organs). Ca signaling is dependent on a tightly regulated Ca gradient, with intracellular free Ca maintained at a low basal level (typically sub-micromolar). This is achieved through the action of proteins intrinsic to the plasma membrane and the membranes of organelles.