A5001730296- Advanced Fluorescence Microscopy Techniques
- Force Microscopy Techniques and Applications
- DNA and Nucleic Acid Chemistry
- Cellular Mechanics and Interactions
- DNA Repair Mechanisms
- Erythrocyte Function and Pathophysiology
- Advanced biosensing and bioanalysis techniques
- Mechanical and Optical Resonators
- Neuroscience and Neuropharmacology Research
- Bacterial Genetics and Biotechnology
- RNA Interference and Gene Delivery
- Lipid Membrane Structure and Behavior
- RNA and protein synthesis mechanisms
- Genomics and Chromatin Dynamics
- RNA Research and Splicing
- Molecular Junctions and Nanostructures
- Advanced Electron Microscopy Techniques and Applications
- Silk-based biomaterials and applications
- Bacteriophages and microbial interactions
- Advanced Biosensing Techniques and Applications
- Cell Image Analysis Techniques
- Near-Field Optical Microscopy
- Monoclonal and Polyclonal Antibodies Research
- Photosynthetic Processes and Mechanisms
- Epigenetics and DNA Methylation
Pennsylvania State University
2022-2023
Howard Hughes Medical Institute
2007-2022
Harvard University
2014-2022
University of Illinois Urbana-Champaign
2007-2019
University of Dundee
2007
Cancer Research UK
2007
Actin, spectrin, and associated molecules form a periodic sub-membrane lattice structure in axons. How this membrane skeleton is developed why it preferentially forms axons are unknown. Here, we studied the developmental mechanism of structure. We found that emerged early during axon development propagated from proximal regions to distal ends Components initial segment were recruited late development. Formation was regulated by local concentration βII which higher than dendrites. Increasing...
Despite the recent advances in single-molecule manipulation techniques, purely mechanical approaches cannot detect subtle conformational changes biologically important regime of weak forces. We developed a hybrid scheme combining force and fluorescence that allowed us to examine effect subpiconewton forces on nanometer scale motion Holliday junction (HJ) at 100-hertz bandwidth. The HJ is an exquisitely sensitive sensor whose response amplified with increase its arm lengths, demonstrating...
Significance Actin, spectrin, and associated molecules form a submembrane periodic skeleton structure in neurons. In this study, we demonstrate that membrane-associated (MPS) is present broad range of neuronal cell types cultured from the central peripheral nervous systems rodents. The MPS preferentially formed axons compared with dendrites differentially regulated at pre- postsynaptic sites Our data also suggest conserved across wide invertebrate vertebrate animal species.
Pif1 family helicases are conserved from bacteria to humans. Here, we report a novel DNA patrolling activity which may underlie Pif1's diverse functions: monomer preferentially anchors itself 3'-tailed junction and periodically reel in the 3' tail with step size of one nucleotide, extruding loop. This periodic is used unfold an intramolecular G-quadruplex (G4) structure on every encounter, sufficient unwind RNA-DNA heteroduplex but not duplex DNA. Instead leaving after G4 unwinding, allowing...
Significance Actin, spectrin, and associated molecules form a quasi-1D periodic membrane skeleton in neurons, which organizes proteins distributions provides mechanical stability for axons. Here, we provide detailed quantifications of this structure neurons show that it develops substantially more slowly dendrites than Moreover, observed 2D, polygonal lattice these the somatodendritic compartment. The diverse structural organizations different developmental courses neuronal compartments...
A dynamic signaling scaffold In neurons, many cellular processes are regulated by receptor tyrosine kinases (RTKs), cell surface receptors whose activation can depend on other pathways. Zhou et al. used super-resolution imaging to visualize colocalization of proteins the membrane-associated periodic skeleton (MPS) that is formed actin, spectrin, and related molecules in axons dendrites neurons. The different pathways leads transactivation RTK, which initiates intracellular signaling. a...
Significance This study describes the crystal structures of full-length PriA DNA helicase, a multifunctional enzyme that mediates essential process restarting prematurely terminated replication reactions in bacteria. Our findings reveal how is able to recognize restart substrates through structure-specific binding and interactions with ssDNA-binding protein it exposes ssDNA could be used reload replisome reinitiate replication. These observations shed light on physical mechanisms allow cells...
Recent development and applications of calibrated, fluorescence resonance energy transfer (FRET)-based tension sensors have led to a new understanding single molecule mechanotransduction in number biological systems. To expand the range accessible forces, we systematically measured FRET versus force trajectories for 25, 40, 50 amino acid peptide repeats derived from spider silk. Single fluorescence-force spectroscopy showed that peptides behaved as linear springs instead nonlinear behavior...
Significance Establishment and maintenance of long axonal projections are essential for brain development function the nervous system. Plasma membrane-associated structural proteins promote axon stability efficient organelle transport, which is thought to be critical in supporting elongation, while both activities long-term survival neurons. This study demonstrates that βII-spectrin axons enables bidirectional transport addition its previously established role forming a periodic...
Abstract Actin, spectrin, and associated molecules form a membrane-associated periodic skeleton (MPS) in neurons. The molecular composition functions of the MPS remain incompletely understood. Here, using co-immunoprecipitation mass spectrometry, we identified hundreds potential candidate MPS-interacting proteins that span diverse functional categories. We examined representative several these categories super-resolution imaging, including previously unknown structural components, as well...
Frequent collisions between cellular DNA replication complexes (replisomes) and obstacles such as damaged or frozen protein make fork progression surprisingly sporadic. These can lead to the ejection of replisomes prior completion replication, which, if left unrepaired, results in bacterial cell death. As such, bacteria have evolved restart mechanisms that function reload onto abandoned forks. Here, we define a direct interaction PriC, key Escherichia coli protein, single-stranded...
Single molecule detection is useful for characterizing nanoscale objects such as biological macromolecules, nanoparticles and nanodevices with nanometer spatial resolution. Fluorescence resonance energy transfer (FRET) widely used a single-molecule assay to monitor intramolecular dynamics in the distance range of 3–8 nm. Here we demonstrate that self-quenching two rhodamine derivatives can be detect small conformational corresponding subnanometer changes FRET-insensitive short-range at...
The telomere-ending binding protein complex CST (Cdc13-Stn1-Ten1) mediates critical functions in both telomere protection and replication. We devised a co-expression affinity purification strategy for isolating large quantities of the complete Candida glabrata complex. was found to exhibit 2∶4∶2 or 2∶6∶2 stoichiometry as judged by ratio subunits native size Stn1, but not Ten1 alone, can directly stably interact with Cdc13. In gel mobility shift assays, Cdc13 manifested high-affinity...
Single-stranded (ss) DNA binding (SSB) proteins play central roles in replication, recombination and repair all organisms. We previously showed that Escherichia coli (Eco) SSB, a homotetrameric bacterial undergoes not only rapid ssDNA-binding mode transitions but also one-dimensional diffusion (or migration) while remaining bound to ssDNA. Whereas the majority of SSB family members function as homotetramers, dimeric were recently discovered distinct lineage extremophiles, Thermus-Deinococcus...