Skip to main content

Juan S. Bonifacino, Ph.D.

NIH Distinguished Investigator

Section on Intracellular Protein Trafficking


Building 35A, Room 2F-226
9000 Rockville Pike
Bethesda, MD 20892


Research Topics

Protein Sorting in the Endosomal-Lysosomal System

We investigate the molecular mechanisms by which transmembrane proteins are sorted to different compartments of the endomembrane system such as endosomes, lysosomes, and a group of cell type–specific organelles known as lysosome-related organelles (e.g., melanosomes and platelet dense bodies). Sorting is mediated by recognition of signals present in the cytosolic domains of the transmembrane proteins by adaptor proteins that are components of membrane coats (e.g., clathrin coats). Among these adaptor proteins are the heterotetrameric AP-1, AP-2, AP-3, and AP-4 complexes, the monomeric GGA proteins, and the heteropentameric retromer complex. Proper sorting requires the function of additional components of the trafficking machinery that mediate vesicle tethering and fusion. Current work in our laboratory is aimed at elucidating the structure, regulation, and physiological roles of coat proteins and vesicle-tethering factors and investigating human diseases that result from genetic defects (e.g., Hermansky-Pudlak syndrome and neurodegenerative and neurodevelopmental disorders) in these proteins.


Dr. Juan Bonifacino received his doctoral degree in biochemistry from the University of Buenos Aires, Argentina, in 1981. He then moved to the NIH, where he pursued postdoctoral studies with Dr. Richard D. Klausner. He rose through the ranks, eventually becoming the Head of the Cell Biology and Metabolism Program. In 2008, he was appointed NIH Distinguished Investigator. Since the early 1990s, Dr. Bonifacino's group has conducted research on signals and adaptor proteins that mediate protein sorting to endosomes and lysosomes. His group discovered new sorting signals and adaptor proteins, and applied this knowledge to the elucidation of the causes of various human diseases including the Hermansky-Pudlak syndrome type 2 and autosomal dominant polycystic liver disease. Dr. Bonifacino has served in various editorial capacities for journals including Developmental Cell, Molecular Cell, Molecular Biology of the Cell, Journal of Cell Biology, Journal of Biological Chemistry and Traffic. He is also the co-editor of the books Current Protocols in Cell Biology and Short Protocols in Cell Biology. He has served as a member of the Council of the American Society for Cell Biology and chaired various scientific conferences. He has delivered the Alex Novikoff, Leonardo Satz, George Connell and G. Burroughs Mider lectures, and is an Honorary Professor of Biological Chemistry at the University of Buenos Aires and a Sackler Lecturer at Tel Aviv University, Israel. His lab has trained over 70 postdoctoral fellows and students, most of whom have pursued careers in academic research.

Selected Publications

  1. Farías GG, Cuitino L, Guo X, Ren X, Jarnik M, Mattera R, Bonifacino JS. Signal-mediated, AP-1/clathrin-dependent sorting of transmembrane receptors to the somatodendritic domain of hippocampal neurons. Neuron. 2012;75(5):810-23.
  2. Schindler C, Chen Y, Pu J, Guo X, Bonifacino JS. EARP is a multisubunit tethering complex involved in endocytic recycling. Nat Cell Biol. 2015;17(5):639-50.
  3. Mattera R, Farías GG, Mardones GA, Bonifacino JS. Co-assembly of viral envelope glycoproteins regulates their polarized sorting in neurons. PLoS Pathog. 2014;10(5):e1004107.
  4. Pu J, Schindler C, Jia R, Jarnik M, Backlund P, Bonifacino JS. BORC, a multisubunit complex that regulates lysosome positioning. Dev Cell. 2015;33(2):176-88.
This page was last updated on October 18th, 2011