POWRE: The Evolving Function of the Basolateral Membrane Ca Pump in Exchange Epithelia of a Continuum of Aquatic to Semi-Terrestrial Brazilian Crabs

点击翻译按钮获取中文摘要

Wheatly 9870374 The grant will allow the PIs to assess how calcium transporting proteins evolved. The PIs will study the physiological function and molecular characterization of the calcium pump in transporting epithelia (gills, kidney, gut) of an evolutionary continuum of related aquatic to semi-terrestrial crabs available in Brazil. Crustaceans are used as a non-mammalian model system for the study of calcium balance due to the mineralization/demineralization processes that accompany their natural molting cycle. The hypothesis is that during evolution from water onto land aquatic modes of Calcium uptake (across gills) become superseded by terrestrial modes (dietary intake across gut). The specific objectives are to examine the Ca uptake proteins in the membrane of gill, kidney and gut in each crab as a function of (a) stage in the molting cycle and (b) CA availability (water or dietary). Methods will include making membrane vesicles (analogous to water filled balloons) to study Ca uptake in vitro as well as using molecular biology to clone and sequence tissue-specific genes. Expression of the genes will be quantified during molting and as a function of Ca availability. The Ca pump is fundamental to Ca homeostasis in all eukaryotic cells. This research will delineate the evolution of this critical molecule over the past 600 million years.