Our goal is to understand the processes that generate compartments of the secretory pathway, including ER exit sites (ERES; also known as transitional ER or tER sites) and the cisternae of the Golgi apparatus. Self-organization models provide the conceptual framework. Specifically, we postulate that ERES are generated together with early Golgi cisternae by an integrated self-organization pathway, and that early cisternae progressively mature into late cisternae.
For exploring these ideas, our main experimental system is a pair of budding yeasts. In Saccharomyces cerevisiae, Golgi cisternae are dispersed throughout the cytoplasm and the ER contains multiple small ERES, whereas in Pichia pastoris, ordered Golgi stacks are located next to large, stable ERES. These two yeasts have complementary advantages for testing specific hypotheses about the secretory pathway. We use a combination of genetics, molecular biology, 4D confocal microscopy, and electron tomography. This work is revealing evolutionarily conserved principles of cellular organization.
A second project in the lab involves optimizing fluorescent proteins, including the red fluorescent protein DsRed. Wild-type DsRed matures very slowly. We overcame this problem by using directed evolution to create the first rapidly maturing DsRed variants, one of which is marketed commercially as DsRed-Express. More recent work yielded a noncytotoxic variant called DsRed-Express2, as well as a far-red variant called E2-Crimson. These engineering efforts inspired a basic research project in which we clarified the pathway of DsRed chromophore formation. Current efforts are focused on creating improved monomeric green and red fluorescent proteins.
Biozentrum, University of Basel
Basel, Switzerland
(postdoc) - Cell Biology
1994
Stanford University
Stanford, CA
PhD - Biochemistry
1988
Amherst College
Amherst, MA
BA - Neuroscience / Mathematics
1983
Functional assignment of Golgi-associated vesicle tethers to specific membrane recycling pathways.
Functional assignment of Golgi-associated vesicle tethers to specific membrane recycling pathways. bioRxiv. 2026 May 21.
PMID: 42239406
COPI-dependent intra-Golgi recycling at an intermediate stage of cisternal maturation.
COPI-dependent intra-Golgi recycling at an intermediate stage of cisternal maturation. J Cell Biol. 2026 Jun 01; 225(6).
PMID: 41996256
Rethinking the Yeast Endomembrane System.
Rethinking the Yeast Endomembrane System. Subcell Biochem. 2026; 110:313-333.
PMID: 41240317
COPI-dependent intra-Golgi recycling at an intermediate stage of cisternal maturation.
COPI-dependent intra-Golgi recycling at an intermediate stage of cisternal maturation. bioRxiv. 2025 Sep 21.
PMID: 41000804
Yellow and oxidation-resistant derivatives of a monomeric superfolder GFP.
Yellow and oxidation-resistant derivatives of a monomeric superfolder GFP. Mol Biol Cell. 2024 Oct 01; 35(10):mr8.
PMID: 39141403
Yellow and oxidation-resistant derivatives of a monomeric superfolder GFP.
Yellow and oxidation-resistant derivatives of a monomeric superfolder GFP. bioRxiv. 2024 Jan 26.
PMID: 38328041
Editorial overview: Membranes in perpetual motion.
Editorial overview: Membranes in perpetual motion. Curr Opin Cell Biol. 2022 10; 78:102128.
PMID: 36103730
Clathrin adaptors mediate two sequential pathways of intra-Golgi recycling.
Clathrin adaptors mediate two sequential pathways of intra-Golgi recycling. J Cell Biol. 2022 01 03; 221(1).
PMID: 34739034
Activity-dependent Golgi satellite formation in dendrites reshapes the neuronal surface glycoproteome.
Activity-dependent Golgi satellite formation in dendrites reshapes the neuronal surface glycoproteome. Elife. 2021 09 21; 10.
PMID: 34545811
TRAPP structures reveal the big picture.
TRAPP structures reveal the big picture. EMBO J. 2021 06 15; 40(12):e108537.
PMID: 34018213