'Interactions among Bcl-2 family proteins mediated by Bcl-2 homology (BH) regions transform apoptosis signals into actions. The interactions between BH3 region-only proteins and multi-BH region proteins such as Bax and Bcl-2 have been proposed to be the dominant interactions required for initiating apoptosis. Experimental evidence also suggests that both homo- ... More
Chemical-genetic inhibition of a sensitized mutant myosin Vb demonstrates a role in peripheral-pericentriolar membrane traffic.
AuthorsProvance DW, Gourley CR, Silan CM, Cameron LC, Shokat KM, Goldenring JR, Shah K, Gillespie PG, Mercer JA
JournalProc Natl Acad Sci U S A
PubMed ID14766983
'Selective, in situ inhibition of individual unconventional myosins is a powerful approach to determine their specific physiological functions. Here, we report the engineering of a myosin Vb mutant that still hydrolyzes ATP, yet is selectively sensitized to an N(6)-substituted ADP analog that inhibits its activity, causing it to remain tightly ... More
Visualizing formation and dynamics of vacuoles in living cells using contrasting dextran-bound indicator: endocytic and nonendocytic vacuoles.
'Here we describe a technique that allows us to visualize in real time the formation and dynamics (fusion, changes of shape, and translocation) of vacuoles in living cells. The technique involves infusion of a dextran-bound fluorescent probe into the cytosol of the cell via a patch pipette, using the whole-cell ... More
Subcellular positioning of small molecules.
AuthorsTakayama S, Ostuni E, LeDuc P, Naruse K, Ingber DE, Whitesides GM
JournalNature
PubMed ID11429594
Stabilization of exocytosis by dynamic F-actin coating of zymogen granules in pancreatic acini.
AuthorsNemoto T, Kojima T, Oshima A, Bito H, Kasai H
JournalJ Biol Chem
PubMed ID15184362
'Reorganization of F-actin in the apical region of mouse pancreatic acinar cells during Ca(2+)-dependent exocytosis of zymogen granules was investigated by two-photon excitation microscopy with intact acini. Granules were rapidly coated with F-actin in response to either agonist stimulation or photolysis of a caged-Ca(2+) compound. Such F-actin coating occurred exclusively ... More
Use of N-[5-(5,7-dimethyl boron dipyrromethene difluoride-sphingomyelin to study membrane traffic along the endocytic pathway.
AuthorsPagano RE, Watanabe R, Wheatley C, Chen CS
JournalChem Phys Lipids
PubMed ID11001561
We have used N-[5-(5,7-dimethyl boron dipyrromethene difluoride)-1-pentanoyl]-D-erythro-sphingosylphosphorylcholine (C5-DMB-SM or 'BODIPY-SM'), a fluorescent analog of sphingomyelin, to study lipid transport along the endocytic pathway of human skin fibroblasts. The unique spectral properties of the BODIPY fluorophore allow the investigator to distinguish various populations of labeled endosomes and lysosomes within the living ... More
Activation of endogenous Cdc42 visualized in living cells.
AuthorsNalbant P, Hodgson L, Kraynov V, Toutchkine A, Hahn KM
JournalScience
PubMed ID15361624
Signaling proteins are tightly regulated spatially and temporally to perform multiple functions. For Cdc42 and other guanosine triphosphatases, the subcellular location of activation is a critical determinant of cell behavior. However, current approaches are limited in their ability to examine the dynamics of Cdc42 activity in living cells. We report ... More
Endocytic trafficking from the small intestinal brush border probed with FM dye.
The small intestinal brush border functions as the body's main portal for uptake of dietary nutrients and simultaneously acts as the largest permeability barrier against pathogens. To enable this, the digestive enzymes of the brush border are organized in lipid raft microdomains stabilized by cross-linking galectins and intelectin, but little ... More
Dynein is required for receptor sorting and the morphogenesis of early endosomes.
AuthorsDriskell OJ, Mironov A, Allan VJ, Woodman PG
JournalNat Cell Biol
PubMed ID17173037
The early endosome is organised into domains to ensure the separation of cargo. Activated mitogenic receptors, such as epidermal growth factor (EGF) receptor, are concentrated into vacuoles enriched for the small GTPase Rab5, which progressively exclude nutrient receptors, such as transferrin receptor, into neighbouring tubules. These vacuoles become enlarged, increase ... More
The mechanism of inhibition of Ran-dependent nuclear transport by cellular ATP depletion.
AuthorsSchwoebel ED, Ho TH, Moore MS
JournalJ Cell Biol
PubMed ID12058015
Rran-dependent nuclear transport requires a nuclear pool of RanGTP both for the assembly of export complexes and the disassembly of import complexes. Accordingly, in order for these processes to proceed, Ran-dependent nuclear import and export assays in vitro require the addition of GTP to produce RanGTP. Notably, no ATP requirement ... More
Probing the cathepsin D using a BODIPY FL-pepstatin A: applications in fluorescence polarization and microscopy.
AuthorsChen CS, Chen WN, Zhou M, Arttamangkul S, Haugland RP
JournalJ Biochem Biophys Methods
PubMed ID10737220
Redistribution of cathepsin D, a major lysosomal aspartic endopeptidase, has been related to various pathological progressions during tumor formation and oxidation stress. We have synthesized a fluorescent probe for cathepsin D, where the pepstatin A was covalently conjugated with the BODIPY (Boron dipyrromethene difluoride) fluorophore. In vitro, BODIPY FL-pepstatin A ... More
Anomalous protein diffusion in living cells as seen by fluorescence correlation spectroscopy.
AuthorsWeiss M, Hashimoto H, Nilsson T
JournalBiophys J
PubMed ID12770908
We investigate the challenges and limitations that are encountered when studying membrane protein dynamics in vivo by means of fluorescence correlation spectroscopy (FCS). Based on theoretical arguments and computer simulations, we show that, in general, the fluctuating fluorescence has a fractal dimension D(0) >or= 1.5, which is determined by the ... More
Fluorescent tracers as potential candidates for double labeling of descending brain neurons in larval lamprey.
AuthorsZhang L, McClellan AD
JournalJ Neurosci Methods
PubMed ID9874141
In larval lamprey, seven fluorescent tracers were tested as potential candidates for retrograde double labeling of descending brain neurons: Fluoro Gold (FG); fluorescein dextran amine (FDA); True Blue (TB); cascade blue dextran amine (CBDA); Fast Blue (FB); Texas red dextran amine (TRDA); and tetramethylrhodamine dextran amine (RDA). The first tracer ... More
tBid elicits a conformational alteration in membrane-bound Bcl-2 such that it inhibits Bax pore formation.
AuthorsPeng J, Tan C, Roberts GJ, Nikolaeva O, Zhang Z, Lapolla SM, Primorac S, Andrews DW, Lin J
JournalJ Biol Chem
PubMed ID17005564
During initiation of apoptosis, Bcl-2 family proteins regulate the permeability of mitochondrial outer membrane. BH3-only protein, tBid, activates pro-apoptotic Bax to release cytochrome c from mitochondria. tBid also activates anti-apoptotic Bcl-2 in the mitochondrial outer membrane, changing it from a single-spanning to a multispanning conformation that binds the active Bax ... More
NMDA receptors mediate calcium accumulation in myelin during chemical ischaemia.
AuthorsMicu I, Jiang Q, Coderre E, Ridsdale A, Zhang L, Woulfe J, Yin X, Trapp BD, McRory JE, Rehak R, Zamponi GW, Wang W, Stys PK
JournalNature
PubMed ID16372019
Central nervous system myelin is a specialized structure produced by oligodendrocytes that ensheaths axons, allowing rapid and efficient saltatory conduction of action potentials. Many disorders promote damage to and eventual loss of the myelin sheath, which often results in significant neurological morbidity. However, little is known about the fundamental mechanisms ... More
Abnormal transport along the lysosomal pathway in mucolipidosis, type IV disease.
AuthorsChen CS, Bach G, Pagano RE
JournalProc Natl Acad Sci U S A
PubMed ID9600972
Mucolipidosis, type IV (ML-IV) is an autosomal recessive storage disease that is characterized by lysosomal accumulation of sphingolipids, phospholipids, and acid mucopolysaccharides. Unlike most other storage diseases, the lysosomal hydrolases participating in the catabolism of the stored molecules appear to be normal. In the present study, we examined the hypothesis ... More
Axonal regeneration and physiological activity following transection and immunological disruption of myelin within the hatchling chick spinal cord.
Transections of the chicken spinal cord after the developmental onset of myelination at embryonic day (E) 13 results in little or no functional regeneration. However, intraspinal injection of serum complement proteins with complement-binding GalC or 04 antibodies between E9-E12 results in a delay of the onset of myelination until E17. ... More
Diphtheria toxin forms pores of different sizes depending on its concentration in membranes: probable relationship to oligomerization.
AuthorsSharpe JC, London E
JournalJ Membr Biol
PubMed ID10501829
Diphtheria toxin forms pores in biological and model membranes upon exposure to low pH. These pores may play a critical role in the translocation of the A chain of the toxin into the cytoplasm. The effect of protein concentration on diphtheria toxin pore formation in model membrane systems was assayed ... More
Local retention of soluble antigen by potential antigen-presenting cells in the anterior segment of the eye.
AuthorsCamelo S, Voon AS, Bunt S, McMenamin PG
JournalInvest Ophthalmol Vis Sci
PubMed ID14638719
PURPOSE: To determine the capacity of bone marrow-derived cells in the anterior segment of the eye to capture a fluorescence-labeled antigen (Ag) injected into the anterior chamber (AC). METHODS: Uveal tract and corneoscleral tissues from Lewis rats were cultured in vitro, with or without FITC-dextran (4 microg/mL final concentration), for ... More
Live Imaging of Intracranial Lymphatics in the Zebrafish.
Authors
JournalCirc Res
PubMed ID33135960
Metformin rescues muscle function in BAG3 myofibrillar myopathy models.
Authors
JournalAutophagy
PubMed ID33030392
Structural and functional conservation of non-lumenized lymphatic endothelial cells in the mammalian leptomeninges.
Authors
JournalActa Neuropathol
PubMed ID31696318
Mitochondria-lysosome contacts regulate mitochondrial fission via RAB7 GTP hydrolysis.
Authors
JournalNature
PubMed ID29364868
Massive centriole production can occur in the absence of deuterosomes in multiciliated cells.
Authors
JournalNat Cell Biol
PubMed ID31792378
Integration of Nodal and BMP Signaling by Mutual Signaling Effector Antagonism.
Authors
JournalCell Rep
PubMed ID32268105
Hyperspectral multiphoton microscopy for in vivo visualization of multiple, spectrally overlapped fluorescent labels.
Authors
JournalOptica
PubMed ID33928182
Dynamic Recruitment of Single RNAs to Processing Bodies Depends on RNA Functionality.
Authors
JournalMol Cell
PubMed ID30952514
Lipid-gated monovalent ion fluxes regulate endocytic traffic and support immune surveillance.
Authors
JournalScience
PubMed ID31806695
Multicolor two-photon imaging of in vivo cellular pathophysiology upon influenza virus infection using the two-photon IMPRESS.