Project description:An 8X15k oligonucleotide microarray was developed consisting of 2334 E. glacialis probes and 2166 Tursiops truncatus probes and used to measure the transcriptome level effects of right whale kidney fibroblast cells exposed to cadmium. Cells were exposed to three concentrations of cadmium chloride (CdCl2) for three exposure times. Cells exposed to 10-6M CdCl2 for 4 hours and 24 hours showed upregulated genes involved in protection from metal toxicity, oxidative stress, protein renaturation, apoptosis inhibition, and several regulators of cellular processes. Downregulated genes represented a suite of functions including cell proliferation, transcription regulation, actin polymerization, and stress fiber synthesis. The collection of differentially expressed genes in this study support proposed mechanisms of cadmium-induced apoptosis such as mitochondrial membrane potential collapse, reactive oxygen species (ROS) influx, and cell cycle arrest. The results confirm the right whale microarray as a reproducible tool in measuring differentiated gene expression and should be a valuable asset for transcriptome analysis of other baleen whales and potential health assessment protocols.
Project description:An 8X15k oligonucleotide microarray was developed consisting of 2334 E. glacialis probes and 2166 Tursiops truncatus probes and used to measure the transcriptome level effects of right whale kidney fibroblast cells exposed to cadmium. Cells were exposed to three concentrations of cadmium chloride (CdCl2) for three exposure times. Cells exposed to 10-6M CdCl2 for 4 hours and 24 hours showed upregulated genes involved in protection from metal toxicity, oxidative stress, protein renaturation, apoptosis inhibition, and several regulators of cellular processes. Downregulated genes represented a suite of functions including cell proliferation, transcription regulation, actin polymerization, and stress fiber synthesis. The collection of differentially expressed genes in this study support proposed mechanisms of cadmium-induced apoptosis such as mitochondrial membrane potential collapse, reactive oxygen species (ROS) influx, and cell cycle arrest. The results confirm the right whale microarray as a reproducible tool in measuring differentiated gene expression and should be a valuable asset for transcriptome analysis of other baleen whales and potential health assessment protocols. 35 Samples were analyzed representing 3 biological replicates for each treatment and corresponding controls except treatment 4hour_0.01uMCdCl2 had only two biological replicates due to spot intensity values. There are 3 spot replicates/probe on the array, along with Agilent control grid specific for 8X15K arrays, and 4 Karenia brevis sequences used as a negative control (K.brevis.chlorophyllA/Bbindingprotein, K.brevis.flavodoxin,K.brevis.photolyase,K.brevis.photosystemcoreprotein).
Project description:North Atlantic right whales (Eubalaena glacialis) feed during the spring and early summer in marine waters off the northeast coast of North America. Their food primarily consists of planktonic copepods, Calanus finmarchicus, which they consume in large numbers by ram filter feeding. The coastal waters where these whales forage are turbid, but they successfully locate copepod swarms during the day at depths exceeding 100 m, where light is very dim and copepod patches may be difficult to see. Using models of E. glacialis visual sensitivity together with measurements of light in waters near Cape Cod where they feed and of light attenuation by living copepods in seawater, we evaluated the potential for visual foraging by these whales. Our results suggest that vision may be useful for finding copepod patches, particularly if E. glacialis searches overhead for silhouetted masses or layers of copepods. This should permit the whales to locate C. finmarchicus visually throughout most daylight hours at depths throughout their foraging range. Looking laterally, the whales might also be able to see copepod patches at short range near the surface.This article is part of the themed issue 'Vision in dim light'.