SALINITY VARIATION AS A PHYSIOLOGICAL LIMIT CONTROL

SYNOPSIS. The molecular processes by which estuarine organisms adjust to salin-ity change are the central focus of this review, with emphasis on identifying the relevant mechanisms in euryhaline crustaceans using the techniques of molecular biology. This review is not intended to be complete with respect to ecological and physiological aspects but rather is an attempt to outline a molecular approach which other investigators may find useful as they address their own specific ques-tions. Membrane transporters of sodium ions serve as the major focus, beginning with an examination of candidate transport systems in gill epithelial cells. Partic-ular emphasis is placed on the recent identification and sequencing of a putative Na+/H+ antiporter cDNA from gills of the green shore crab Carcinus maenas