A5061614430- Cellular transport and secretion
- Lipid Membrane Structure and Behavior
- Genomics and Chromatin Dynamics
- Advanced Electron Microscopy Techniques and Applications
- Protist diversity and phylogeny
- Microtubule and mitosis dynamics
- Chromatin Remodeling and Cancer
- Ubiquitin and proteasome pathways
- Endoplasmic Reticulum Stress and Disease
- RNA Research and Splicing
- DNA and Nucleic Acid Chemistry
- Cancer Mechanisms and Therapy
- Antimicrobial Resistance in Staphylococcus
- Bacterial Genetics and Biotechnology
- RNA and protein synthesis mechanisms
- Photosynthetic Processes and Mechanisms
- Fungal and yeast genetics research
- Retinal Development and Disorders
- Membrane Separation Technologies
- Protein Degradation and Inhibitors
- Solid-state spectroscopy and crystallography
- Diffusion and Search Dynamics
- Agriculture and Rural Development Research
- Advanced Biosensing Techniques and Applications
- Cephalopods and Marine Biology
University of North Carolina at Chapel Hill
2010-2024
University of California, San Diego
2018-2023
UNC Lineberger Comprehensive Cancer Center
2020-2023
Communities In Schools of Orange County
2023
Princeton University
2013-2018
Colorado State University
1974
Unravelling the SM-SNARE conundrum So-called SNARE proteins mediate and lend specificity to fusion between different intracellular membranes. The SM are universally required for vesicle fusion, yet their mechanism of action has long been enigmatic. Baker et al. have solved a piece puzzle by “capturing” SNAREs in process assembling into fusogenic complexes on surface an protein. findings suggest exactly how why help vesicular during membrane trafficking. Science , this issue p. 1111
Sec1/Munc18-family (SM) proteins are required for SNARE-mediated membrane fusion, but their mechanism(s) of action remain controversial. Using single-molecule force spectroscopy, we found that the SM protein Munc18-1 catalyzes step-wise zippering three synaptic SNAREs (syntaxin, VAMP2, and SNAP-25) into a four-helix bundle. Catalysis requires formation an intermediate template complex in which juxtaposes N-terminal regions SNARE motifs syntaxin while keeping C-terminal separated. SNAP-25...
Abstract Staphylococcus aureus is a Gram-positive pathogen responsible for antibiotic-resistant infections. To identify vulnerabilities in cell envelope biogenesis that may overcome resistance, we enriched S. transposon mutants with defects surface integrity or division by sorting cells stain propidium iodide have increased light-scattering properties, respectively. Transposon sequencing of the sorted populations identified more than 20 previously uncharacterized factors impacting these...
The catalytic subunits of SWI/SNF-family and INO80-family chromatin remodelers bind actin actin-related proteins (Arps) through an N-terminal helicase/SANT-associated (HSA) domain. Between the HSA ATPase domains lies a conserved post-HSA (pHSA) domain Sth1, subunit yeast remodeler RSC, recruits Rtt102-Arp7/9 heterotrimer. regulates RSC function, but mechanism is unclear. We show that pHSA interacts directly with another region subunit, protrusion-1. binding to weakens this interaction...
Intracellular membrane fusion requires the regulated assembly of SNARE (soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein receptor) proteins anchored in apposed membranes. To exert force required to drive between lipid bilayers, juxtamembrane motifs zipper into four-helix bundles. Importantly, function is by additional factors, none more extensively studied than SM (Sec1/Munc18-like) proteins. interact with both individual SNAREs and complexes, likely chaperoning complex...
The exocyst imparts spatial control during exocytic vesicle tethering through its interactions with proteins and lipids on the plasma membrane. One such interaction is tether Sro7, although outcome of this poorly understood. Here, we describe how Sro7 binding to Exo84 subunit results in activation complex which leads an increase avidity for Rab GTPase Sec4 exocyst-mediated tethering. Gain-of-function (GOF) mutations that mimic replicate these biochemical changes result allosteric within...
The Cullin 5 (CUL5) Ring E3 ligase uses adaptors Elongins B and C (ELOB/C) to bind different SOCS-box-containing substrate receptors, determining the specificity of ligase. 18-member ankyrin SOCS box (ASB) family is largest receptor family. Here we report cryo-EM data for substrate, creatine kinase (CKB) bound ASB9-ELOB/C, full-length CUL5 RING protein, RBX2, which binds various E2s. To date, no full structures are available either a substrate-bound ASB nor CUL5. Hydrogen-deuterium exchange...
Adaptor protein complex-3 (AP-3) mediates cargo sorting from endosomes to lysosomes and lysosome-related organelles. Recently, it was shown that AP-3 adopts a constitutively open conformation compared the related AP-1 AP-2 coat complexes, which are inactive until undergoing large conformational changes upon membrane recruitment. How is regulated therefore an question. To understand mechanism of recruitment activation, we reconstituted human determined multiple structures in soluble...
Endocytosis of transmembrane proteins is orchestrated by the AP2 clathrin adaptor complex. dwells in a closed, inactive state cytosol, but adopts an open, active conformation on plasma membrane. Membrane-activated complexes are also phosphorylated, significance this mark debated. We recently proposed that NECAP negatively regulates binding open and phosphorylated (Beacham et al., 2018). Here, we report high-resolution cryo-EM structures bound to AP2. The site phosphorylation directly...
SUMMARY Staphylococcus aureus is a gram-positive pathogen responsible for life-threatening infections that are difficult to treat due antibiotic resistance. The identification of new vulnerabilities in essential processes like cell envelope biogenesis represents promising avenue towards the development anti-staphylococcal therapies overcome To this end, we performed sorting-based enrichments S. mutants with defects integrity and division. We identified many known factors as well large...
The C-terminal domain (CTD) of the largest subunit RNA polymerase II (RNAPII) is required to regulate transcription and integrate it with other essential cellular processes. In budding yeast
Abstract Cytoplasmic dynein-1 is a molecular motor that drives nearly all minus-end-directed microtubule-based transport in human cells, performing functions ranging from retrograde axonal to mitotic spindle assembly 1,2 . Activated dynein complexes consist of one or two dimers, the dynactin complex, and an “activating adaptor”, with maximal velocity seen dimers present (Fig. 1a) 3-6 Little known about how this massive ∼4MDa complex assembled. Using purified recombinant proteins, we...
Abstract Sec1/Munc18-family (SM) proteins are required for SNARE-mediated membrane fusion, but their mechanism(s) of action remain controversial. Using single-molecule force spectroscopy, we found that the SM protein Munc18-1 catalyzes step-wise zippering three synaptic SNAREs (syntaxin, VAMP2, and SNAP-25) into a four-helix bundle. Catalysis requires formation an intermediate template complex in which juxtaposes N-terminal regions SNARE motifs syntaxin while keeping C-terminal separated....