Current Lab Members

Dr. Michael S. Marks

Professor of Pathology and Laboratory Medicine • Cornell University (B.S.), Duke University (Ph.D.)
 marksm@pennmedicine.upenn.edu
 Publications

My lab focuses on molecular mechanisms controlling membrane trafficking and morphogenesis during the formation of lysosome-related organelles in several cell types, and how these mechanisms are disrupted in disease. We have largely focused particularly on the biogenesis of melanosomes – lysosome-related organelles in which melanin is synthesized and stored in skin melanocytes and in choroid melanocytes, retinal pigment epithelia, and iris pigment epithelia in the eye. Defects in melanosome biogenesis result in ocular or oculocutaneous albinism either in isolation (non-syndromic albinism) or as part of a broader disease of lysosome-related organelle biogenesis (syndromic albinism, e.g. the Hermansky-Pudlak syndromes). We have also worked with collaborators to extend our findings on melanosomes into other systems, including the formation of dense granules in platelets (required for optimal blood clotting), the formation of lamellar bodies in lung epithelial cells (required for surfactant secretion in the lung), and the maturation of phagosomes in dendritic cells (required for innate immunity and antigen presentation in the immune system). These systems are related through their disruption in rare diseases of membrane trafficking components such as the Hermansky-Pudlak syndromes. More recently, we have collaborated with others to investigate the mechanisms by which genes that control natural pigment variation in human populations function in melanocytes. This has led us to investigate other rare diseases, including ciliopathies such as Joubert syndrome and Bardet-Biedl syndrome.

Dawn Harper

Research Associate • West Chester University of Pennsylvania (B.S.) • University of Pennsylvania (M.S.)
 sabine1913@gmail.com
 Publications

My work is focused on understanding how specific proteins and protein complexes are assembled and sorted to the appropriate compartments within the late secretory and endocytic pathways, and how sorting and assembly contributes to the biogenesis of lysosome-related organelles (LROs) and the diseases resulting from malformation of LROs in specialized cells. 

Roseanne Davila-Rivera

BBCB Graduate Group PhD Candidate • Universidad de Puerto Rico (B.S., 2014)
 rdavilar@pennmedicine.upenn.edu
 Publications

Dr. Brice Magne

Postdoctoral Researcher • Paris-Sud University (Ph.D., 2019)
 magneb@chop.edu
 Publications

Rachel Welles

CAMB Graduate Group, Ph.D. Candidate • Haverford College (B.S., 2021)
 rachel.welles@pennmedicine.upenn.edu
 Publications

My work explores the function of BLOC-2 in melanosome motility in biogenesis primarily through live-cell microscopy and particle tracking.