Abstract: The kidney plays a central role in maintaining the systemic fluid and electrolyte homeostasis in the body through epithelial reabsorption and urinary excretion. The transepithelial transport of fluid and solutes in the kidney depends on a series of membrane channels and transporters specifically expressed in the apical and/or basolateral membrane of different segments of renal tubules. The SoLute Carrier family 4 (SLC4) represents a major HCO3– transporter family that includes five Na+-dependent HCO3– transporters (NBCs) and three Na+-independent Cl−/HCO3– exchangers. The SLC4 family HCO3– transporters are widely expressed in the epithelia along different segments of the renal tubule and play an essential role in the transport of acid-base and NaCl in the kidney. Genetic studies have demonstrated that dysfunction of the SLC4 family transporters are associated with the development of severe renal tubular metabolic acidosis, hypertension, mental disrorders, migraine etc. In the past decade, enormous progresses have been made in understanding the physological roles of the SLC4 family HCO3– transporters in the kidney. These progresses have greatly advanced our knowledge about the pathophysiological mechanism underlying the diseases associated with the SLC4 family genes. In the presentation, I will talk about our latest findings about the physiological roles of the SLC4 family transporters for the transport of acid-base equivalents and NaCl in the kidney, as well as new molecuar mechanism underlying the functional regulation of these transporters.

Keywords: Membrane transporter; Renal reabsorption; Hypertension; Metabolic acidosis; Protein interaction; Ion transport; Epithelium.

Biography: Dr. Liming Chen is a professor of physiology and biophysics at Huazhong University of Science and Technology. He took his undergraduate study and then PhD study in biochemistry at Peking University. After receiving his PhD in 2002, Dr. Chen turned his research interest to biophysics and physiology during his postdoctoral study with Dr. Walter F. Boron at Yale University. He joined the faculty at Huazhong University of Science and Technology in 2009.
The research in Dr. Chen’s lab focuses on a fundamental biological problem, i.e., the movement of ions across cell membranes. Specifically, he is interested in a group of secondary active transporters, namely, the Na+-coupled HCO3– transporters of the SLC4 family. The studies in his lab aim to understand the biophysical and physiological aspects of these transporters on the molecular level by using multidisciplinary approaches, including electrophysiology, biochemistry, cell biology, structural biology, animal models, etc. These studies fall into three major areas: (1) Structure and function of acid-base transporters; (2) Protein-protein interaction and functional regulation of acid-base transporters; (3) Physiological and pathophysiological roles of acid-base transporters in the kidney.