Fish liver protein synthesis during cold acclimatization: seasonal changes of the ultrastructure of the carp hepatocyte [Cyprinus carpio]

A cell‐free system, active in protein synthesis, was constructed using ribosomes and supernatant factors isolated from the livers of winteracclimatized carps. Upon seasonal adaptation, the hepatocytes of these fishes exhibited distinctive morphological features that were not sex dependent. The cytoarchitecture of the liver cell from summer carps is consistent with the cellular arrangements found when the rate of gene expression is high. During winter, several morphological features reveal that macromolecular synthetic activity may be clearly diminished.