Molecular aspects of chloride cell formation in Oncorhynchus. I. Isolation and characterization of ribosomes involved in protein synthesis

Abstract

The present investigation has developed techniques for the reproducible isolation of polyribosomes from gill filaments of Oncorhynchus nerka, O. kisutch, O. tshawytscha, and Salmo gairdneri. A basic pattern of aggregated complexes was resolved in microsomal and deoxycholate-treated fractions that was consistent with the ultrastructural observations made by electron microscopy. The relative amino acid incorporating activity was assessed in vivo and the association with particular polyribosomal classes was made. Gill filaments undergoing active salt secretion have smaller polysomes involved in protein synthesis than non-secreting gill filaments. Increased protein synthesis appears correlated with development of chloride cells.