The Renal Section of the American Physiological Society is pleased to announce that the 2002 recipient of the AstraZeneca Young Investigator Award for Excellence in Renal Physiology is Dr. Jonathan Barasch, Assistant Professor of Medicine, Columbia College of Physicians and Surgeons of Columbia University. The purpose of this award is to recognize an outstanding young investigator working in any area of renal physiology or hypertension. Dr. Barasch presented his keynote lecture, “Formation of Epithelia in the Embryonic Kidney,” in the Featured Topic session “Development of the Kidney from Mesenchyme and Ureteric Bud” at the Experimental Biology 2002 meeting held in New Orleans, Louisiana, April 20–24, 2002. He received his AstraZeneca Young Investigator Award during the Renal Dinner on Tuesday, April 23, 2002. This award is presented annually at the Experimental Biology meeting and is made possible by the generous support of the AstraZeneca, PLC, Wilmington, Delaware.
Dr. Barasch's interest in research began in high school while working in the laboratory of R. Bressler at Mt. Sinai Hospital, New York, NY. This work culminated in publication of his first paper, a study that described the postnatal development of the male reproductive tract. He went on to receive a BA in Biochemistry, Magna Cum Laude, from Dartmouth College in 1980.
Dr. Barasch continued his biomedical research in the laboratories of Michael Gershon, Eladio Nunez, and Hadassah Tamir while a student in the MD, PhD Program at Columbia College of Physicians and Surgeons of Columbia University. His work as a graduate student led to a model system for the study of serotonergic neurons. He demonstrated that the thyroid parafollicular cell, an endocrine cell that synthesizes serotonin, could be converted into a serotonergic neuron. He then went on to study the mechanism of the storage of this neurotransmitter in subcellular organelles in these cells. He isolated their dense cored vesicles, showed that they actively take up serotonin, and then showed that, unlike most other intracellular organelles, they failed to acidify their interior. In collaboration with Qais Al-Awqati, Dr. Barasch found that acidification was regulated by a vesicular chloride channel that varied its activity depending on cell stimulation by secretogogues. The work was the first to demonstrate regulation of the pH of a subcellular organelle by signaling molecules. The role of this signaling pathway in cystic fibrosis was explored during his postdoctoral fellowship in the laboratory of Qais Al-Awati.
After completion of his fellowship, Dr. Barasch joined the faculty in the Division of Nephrology at Columbia College of Physicians and Surgeons of Columbia University. At that time, his work turned to the study of the developing kidney. In the developing kidney, epithelia are created from the metanephric mesenchyme after a signal from an adjacent structure called the ureteric bud. These signaling events had not been defined, however, in part because of the complexity of demonstrating a signaling pathway in a system of reciprocating interactions between mesenchyme and ureteric bud. Thus cell lines from the ureteric bud were developed, and a series of molecules secreted from these cells were identified to cause either growth of mesenchymal cells or their conversion into epithelia. They observed that combinations of these molecules can produce over 100 early nephrons, replete with glomeruli and proximal and distal tubules. Dr. Barasch's laboratory is the first group to convert mesenchyme to epithelia using purified molecules. They anticipate purification of six distinct inducing factors.
There are a number of consequences of this work, including the identification of different subsets of epithelial precursors. One of these subsets was visible in the mesenchyme and could be easily isolated from surrounding cells. This new work is revealing the role of signaling between cell types within the metanephric mesenchyme, including an inhibitory signaling pathway from stroma to epithelial precursor.
The APS Renal Section AstraZeneca Young Investigator Award Selection Committee, a subcommittee of the Renal Section Steering Committee, included Susan Wall, Joseph Handler, Michael Caplan and Jurgen Schnermann. The Renal Section wishes to express its sincere appreciation to the Scientific Commercialization Skill Center of AstraZeneca, PLC, for its generous support of biomedical education.
- Copyright © 2002 the American Physiological Society