Santiago Di Pietro Professor and Associate Dean for Research


Phone: (970) 491-5302


  • Ph.D., University of Buenos Aires
  • Postdoctoral Fellow, University of California at Los Angeles Medical School


This cell biology laboratory focuses on fundamental aspects of intracellular protein transport.  We are particularly interested in clathrin mediated endocytosis and transport pathways to melanosomes, platelet granules and other lysosome related organelles (LROs).  The physiological significance of these pathways is manifold.  The endocytic pathway is required for nutrient uptake, down-regulation of signal transduction events, antigen presentation, and virus internalization, while the biosynthetic pathways to LROs are critical for the biogenesis and function of these organelles.  A wide range of diseases are caused by defects in these pathways including heart disease, bleading disorders and albinism.  We have gained a solid expertise in the integrated use of biochemistry, biophysics, microscopy, mammalian and yeast cell biology, and genetics. We are applying that experience to identify new components of the transport machinery, to study novel mechanisms regulating clathrin coat formation, and to understand the link between the transport machinery and the actin cytoskeleton. Our work has implications not only in basic cell biology but also in deciphering the pathogenesis of diseases associated with defects in protein transport pathways.


  • OCA7 is a melanosome membrane protein that defines pigmentation by regulating early stages of melanosome biogenesisBeyers W.C., Detry A.M., Di Pietro S.M.J. Biol. Chem., In Press, 2022
  • Syntaxin 12 and COMMD3 are new factors that function with VPS33B in the biogenesis of platelet alpha-granulesAmbrosio A.L., Febvre H.P., Di Pietro S.M.Blood, 139:922-935, 2022
  • The dynein light chain protein Tda2 functions as a dimerization engine to regulate actin capping protein during endocytosisLamb A.K., Fernandez A.N., Peersen O.B. and Di Pietro S.M.Mol. Biol. Cell, 32:1459-1473, 2021
  • Cargo-Mediated Recruitment of the Endocytic Adaptor Protein Sla1 in S. cerevisiaeTolsma T.O., Febvre H., Olson D.M., Di Pietro S.M. J. Cell Science. 133(19): jcs247684, 2020
  • Mechanism of platelet a-granule biogenesis: study of cargo transport and the VPS33B-VPS16B complex in a model systemAmbrosio A.L., Di Pietro S.M.Blood Advances 3(17): 2617-2626., 2019
  • The Sla1 adaptor-clathrin interaction regulates coat formation and progression of endocytosisTolsma T.O., Cuevas L.M., Di Pietro S.M. Traffic, 19:446-462, 2018
  • Novel function of a dynein light chain in actin assembly during clathrin mediated endocytosisFarrell K.B., McDonald S., Lamb A.K., Worcester C., Peersen O.B., Di Pietro S.M.The Journal of Cell Biology, 216:2565-2580, 2017
  • Storage pool diseases illuminate platelet dense granule biogenesisAmbrosio A.L., Di Pietro S.M.Platelets, 28:138-146, 2017
  • Reduce, reuse, recycle: a retrieval transport pathway for the membrane fusion machinery involved in melanosome biogenesisBultema J.J., Di Pietro S.M.Pigment Cell Melanoma Res. 30:10-12, 2017
  • TPC2 controls pigmentation by regulating melanosome pH and sizeAmbrosio A.L., Boyle J.A., Aradi A., Christian K.A., Di Pietro S.M. Proc. Natl. Acad. Sci. USA. 113:5622-5627, 2016