Long-term waterborne Cu exposure affects collagen metabolism in fish.

Copper pollution might have a negative effect on collagen metabolism in fish. To test this hypothesis, we exposed an important economical fish, silver pomfret (Pampus argenteus), to three concentrations of Cu for up to 21 days to simulate natural exposure to copper. With increasing copper exposure concentration and time, hematoxylin and eosin staining and picrosirius red staining revealed extensive vacuolization, cell necrosis, and tissue structure destruction, and a change of type and abnormal accumulation of collagen in the liver, intestine, and muscle tissues.

Selection of reference genes for quantitative real-time RT-PCR analysis in citrus.

Quantitative real-time reverse transcription polymerase chain reaction (qPCR) has become the preferred method for studying low-abundant mRNA expression. Appropriate application of qPCR in such studies requires the use of reference gene(s) as an internal control in order to normalize the mRNA levels between different samples for an exact comparison of gene expression levels. Expression of the reference gene should be independent from development stage, cell/tissue types, treatments and environmental conditions.