'To gain a molecular understanding of tumor angiogenesis, we compared gene expression patterns of endothelial cells derived from blood vessels of normal and malignant colorectal tissues. Of over 170 transcripts predominantly expressed in the endothelium, 79 were differentially expressed, including 46 that were specifically elevated in tumor-associated endothelium. Several of ... More
The initial events in myelin synthesis: orientation of proteolipid protein in the plasma membrane of cultured oligodendrocytes.
AuthorsHudson LD, Friedrich VL, Behar T, Dubois-Dalcq M, Lazzarini RA
JournalJ Cell Biol
PubMed ID2474554
'Proteolipid protein (PLP) is the most abundant transmembrane protein in myelin of the central nervous system. Conflicting models of PLP topology have been generated by computer predictions based on its primary sequence and experiments with purified myelin. We have examined the initial events in myelin synthesis, including the insertion and ... More
A Rab11-containing rapidly recycling compartment in macrophages that promotes phagocytosis.
AuthorsCox D, Lee DJ, Dale BM, Calafat J, Greenberg S
JournalProc Natl Acad Sci U S A
PubMed ID10639139
'Macrophages are specialized cells of the immune system that exhibit a prodigious capacity for phagocytosis. The ability of macrophages to internalize a substantial proportion of their plasma membrane during phagocytosis indicates that they possess a mechanism for the rapid renewal of plasma membrane. We examined the role of endocytic membrane ... More
Nuclear ferritin protects DNA from UV damage in corneal epithelial cells.
AuthorsCai CX, Birk DE, Linsenmayer TF
JournalMol Biol Cell
PubMed ID9571238
'Previously, we identified the heavy chain of ferritin as a developmentally regulated nuclear protein of embryonic chicken corneal epithelial cells. The nuclear ferritin is assembled into a supramolecular form indistinguishable from the cytoplasmic form of ferritin found in other cell types and thus most likely has iron-sequestering capabilities. Free iron, ... More
Altered cytochrome c display precedes apoptotic cell death in Drosophila.
AuthorsVarkey J, Chen P, Jemmerson R, Abrams JM
JournalJ Cell Biol
PubMed ID10037791
'Drosophila affords a genetically well-defined system to study apoptosis in vivo. It offers a powerful extension to in vitro models that have implicated a requirement for cytochrome c in caspase activation and apoptosis. We found that an overt alteration in cytochrome c anticipates programmed cell death (PCD) in Drosophila tissues, ... More
Single-molecule fluorescence observed with mercury lamp illumination.
AuthorsUnger M, Kartalov E, Chiu CS, Lester HA, Quake SR
JournalBiotechniques
PubMed ID10572649
We demonstrate that it is possible to observe single fluorescent molecules using a standard fluorescence microscope with mercury lamp excitation and an inexpensive cooled charge-coupled device (CCD) camera. With this equipment, we have been able to observe single molecules of tetramethyl-rhodamine, rhodamine 6G, fluorescein isothiocyanate and green fluorescent protein. Immobilized ... More
Enterocyte TLR4 mediates phagocytosis and translocation of bacteria across the intestinal barrier.
AuthorsNeal MD, Leaphart C, Levy R, Prince J, Billiar TR, Watkins S, Li J, Cetin S, Ford H, Schreiber A, Hackam DJ,
JournalJ Immunol
PubMed ID16493066
Translocation of bacteria across the intestinal barrier is important in the pathogenesis of systemic sepsis, although the mechanisms by which bacterial translocation occurs remain largely unknown. We hypothesized that bacterial translocation across the intact barrier occurs after internalization of the bacteria by enterocytes in a process resembling phagocytosis and that ... More
CD40, an extracellular receptor for binding and uptake of Hsp70-peptide complexes.
AuthorsBecker T, Hartl FU, Wieland F
JournalJ Cell Biol
PubMed ID12356871
Tumor and viral antigens elicit a potent immune response by heat shock protein-dependent uptake of antigenic peptide with subsequent presentation by MHC I. Receptors on antigen-presenting cells that specifically bind and internalize a heat shock protein-peptide complex have not yet been identified. Here, we show that cells expressing CD40, a ... More
Contacts and cooperation between cells depend on the hormone ouabain.
AuthorsLarre I, Ponce A, Fiorentino R, Shoshani L, Contreras RG, Cereijido M
JournalProc Natl Acad Sci U S A
PubMed ID16835298
Cell adhesion is a crucial step in proliferation, differentiation, migration, apoptosis, and metastasis. In previous works we have shown that cell adhesion is modulated by ouabain, a highly specific inhibitor of Na+,K+-ATPase, recently found to be a hormone. In the present work we pursue the investigation of the effect of ... More
A dominant-negative clathrin mutant differentially affects trafficking of molecules with distinct sorting motifs in the class II major histocompatibility complex (MHC) pathway.
AuthorsLiu SH, Marks MS, Brodsky FM
JournalJ Cell Biol
PubMed ID9490717
The role of clathrin in intracellular sorting was investigated by expression of a dominant-negative mutant form of clathrin, termed the hub fragment. Hub inhibition of clathrin-mediated membrane transport was established by demonstrating a block of transferrin internalization and an alteration in the intracellular distribution of the cation-independent mannose-6-phosphate receptor. Hubs ... More
Ii chain controls the transport of major histocompatibility complex class II molecules to and from lysosomes.
AuthorsBrachet V, Raposo G, Amigorena S, Mellman I
JournalJ Cell Biol
PubMed ID9105036
Major histocompatibility complex class II molecules are synthesized as a nonameric complex consisting of three alpha beta dimers associated with a trimer of invariant (Ii) chains. After exiting the TGN, a targeting signal in the Ii chain cytoplasmic domain directs the complex to endosomes where Ii chain is proteolytically processed ... More
Molecular and functional characterization of the non-isopeptide-selective ETB receptor in endothelial cells. Receptor coupling to nitric oxide synthase.
AuthorsTsukahara H, Ende H, Magazine HI, Bahou WF, Goligorsky MS
JournalJ Biol Chem
PubMed ID7520443
There is accumulating evidence that endothelial cells express a non-isopeptide-selective endothelin (ET) receptor, ETB, which may be responsible for ET-1-induced transient vasorelaxation. The purpose of the present study was to seek direct evidence for ETB receptor expression in human umbilical vein endothelial cells (HUVEC) and to characterize its functional role ... More
Intracellular distribution of transgenic bacterial beta-galactosidase in central nervous system neurons and neuroglia.
AuthorsFriedrich VL, Holstein GR, Li X, Gow A, Kelley KA, Lazzarini RA
JournalJ Neurosci Res
PubMed ID8230324
Bacterial beta-galactosidase is widely used as a marker for gene expression and in cell tracing experiments. In a survey of three transgenic mouse lines expressing beta-galactosidase in the central nervous system (CNS) under the control of different promoters, we find substantial variation in the intracellular distribution of the lacZ protein. ... More