Abstract：
:To examine the internal structure of chromatin fibers, we have developed procedures for partial denaturation of small chromatin fragments (8-30 nucleosomes) from chicken erythrocytes. Electron micrographs of samples prepared under conditions that cause nucleosome dissociation show rods and loops projecting from short compact fibers fixed by glutaraldehyde in 1.7 mM Mg2+. According to previous studies in our laboratory, these images correspond to the top view of partially denatured fibers. Our results indicate that rods and loops consist of extended duplex DNA of different lengths. DNA in loops is nicked, as demonstrated by experiments performed in the presence of high concentrations of ethidium bromide. Length measurements indicate that the radial projections of DNA are produced by unfolding of nucleosomal units. Loops are formed by DNA from denatured nucleosomes in internal positions of the fiber; DNA from denatured nucleosomes in terminal positions form rods. Our micrographs show clearly a radial distribution of DNA loops and rods projecting from fibers. Rods are orthogonal to the surface of the chromatin fragments. Considering that the high ionic strength used in this study (0.8-2.0 M NaCl) neutralizes the electrostatic repulsions between rods and fiber, this observation suggests that rods are extensions of nucleosomes radially organized inside the fiber. The position of the entry points of DNA loops into the fiber could be influenced by constraint on loops, but our results showing that the arc that separates these points in dinucleosome loops is relatively short suggest that consecutive nucleosomes are relatively close to each other in the folded fiber.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Bermúdez A,Bartolomé S,Daban JRsubject
Has Abstractpub_date
1998-06-01 00:00:00pages
1707-15eissn
0021-9533issn
1477-9137journal_volume
111 ( Pt 12)pub_type
杂志文章abstract：:The structure of a late endosomal compartment, which contains the bulk of the cation-independent mannose 6-phosphate receptor (MPR) in NRK cells, is documented using immunocytochemistry and cryo-sections, as well as conventional Epon sections. This compartment, which we refer to as the prelysosomal compartment (PLC), ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：:Chloroquine resistance in the human malaria parasite, Plasmodium falciparum, arises from decreased accumulation of the drug in the ;digestive vacuole' of the parasite, an acidic compartment in which chloroquine exerts its primary toxic effect. It has been proposed that changes in the pH of the digestive vacuole might ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02795
更新日期：2006-03-15 00:00:00
abstract：:The E-cadherin-catenin complex regulates Ca(2+)-dependent cell-cell adhesion and is localized to the basolateral membrane of polarized epithelial cells. Uncoupling beta-catenin from E-cadherin by deletion or substitution mutations causes accumulation of these proteins in intracellular compartments, including the trans...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03489
更新日期：2007-12-15 00:00:00
abstract：:Naegleria gruberi is a single-celled eukaryote best known for its remarkable ability to form an entire microtubule cytoskeleton de novo during its metamorphosis from an amoeba into a flagellate, including basal bodies (equivalent to centrioles), flagella and a cytoplasmic microtubule array. Our publicly available full...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.077453
更新日期：2010-12-01 00:00:00
abstract：:The Birt-Hogg-Dubé (BHD) syndrome related protein FLCN has recently been implicated in the vesicular trafficking processes by interacting with several Rab family GTPases. In the previous studies, we have shown that FLCN could inhibit the binding of overexpressed PAT1, which is a membrane-bound amino acid transporter, ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.218792
更新日期：2018-12-19 00:00:00
abstract：:Hepatocyte growth factor, also known as scatter factor, is a pleiotropic cytokine, which stimulates cell motility, invasion, proliferation, survival and morphogenesis, and induces the expression of specific genes by activating its receptor tyrosine kinase. In this work we have isolated, characterized and used as agoni...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1998-01-01 00:00:00
abstract：:Loss of tissue organization is a hallmark of the early stages of cancer, and there is considerable interest in proteins that maintain normal tissue architecture. Prostate epithelial cells cultured in Matrigel form three-dimensional acini that mimic aspects of prostate gland development. The organization of these struc...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.119388
更新日期：2013-04-15 00:00:00
abstract：:Hemidesmosomes are epithelial-specific attachment structures that maintain tissue integrity and resist tension. Despite their importance, how hemidesmosomes are regulated at the post-transcriptional level is poorly understood. Caenorhabditiselegans hemidesmosomes (CeHDs) have a similar structure and composition to the...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.214379
更新日期：2018-06-11 00:00:00
abstract：:We have previously demonstrated that the subcellular distribution of the adhesion plaque protein, talin, changes dramatically in human platelets in response to platelet activation (Beckerle et al., J. Cell Biol. 109, 3333-3346, 1989). Talin is uniformly distributed throughout the cytoplasm of resting platelets. Howeve...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1993-12-01 00:00:00
abstract：:The mucolipin (TRPML) subfamily of transient receptor potential (TRP) cation channels consists of three members that play various roles in the regulation of membrane and protein sorting along endo-lysosomal pathways. Loss-of-function mutations in TRPML1 cause the neurodegenerative lysosomal storage disorder, mucolipid...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.067330
更新日期：2010-09-15 00:00:00
abstract：:In the fission yeast Schizosaccharomyces pombe, the protein kinase Chk1 has an essential role in transducing a delay signal to the cell cycle machinery in the presence of DNA damage. Fission yeast cells lacking the chk1 gene do not delay progression of the cell cycle in response to damage and are thus sensitive to DNA...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00133
更新日期：2002-12-01 00:00:00
abstract：:We have investigated the role in macrophage lysosomal enzyme release of arachidonate metabolites, extracellular divalent cations and cyclic AMP (cAMP) which modulate secretion in other cell types. Lysosomal enzyme secretion induced by zymosan was accompanied by release of malondialdehyde (MDA), which is derived from a...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1980-08-01 00:00:00
abstract：:A complex network of interactions between the stroma, the extracellular matrix and the epithelium drives mammary gland development and function. Two main assumptions in chemical carcinogenesis of the mammary gland have been that carcinogens induce neoplasia by causing mutations in the DNA of the epithelial cells and t...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01000
更新日期：2004-03-15 00:00:00
abstract：:Cofilin has emerged as a key regulator of actin dynamics at the leading edge of motile cells. Through its actin-severing activity, it creates new actin barbed ends for polymerization and also depolymerizes old actin filaments. Its function is tightly regulated in the cell. Spatially, its activity is restricted by othe...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01631
更新日期：2005-01-01 00:00:00
abstract：:Increases in cytosolic Ca(2+) concentration ([Ca(2+)](c)) mediated by inositol (1,4,5)-trisphosphate [Ins(1,4,5)P(3), hereafter InsP(3)] regulate activities that include division, contraction and cell death. InsP(3)-evoked Ca(2+) release often begins at a single site, then regeneratively propagates through the cell as...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.105163
更新日期：2012-11-15 00:00:00
abstract：:Studies of cellular function in the respiratory tract lining have traditionally been limited by the small tissue mass and functional diversity of the epithelium. Recent improvements in culture conditions have permitted long-term maintenance of epithelial cells derived from the upper respiratory tract of rats. The pres...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1978-08-01 00:00:00
abstract：:Eggs of Urechis caupo are surrounded by a congruent to 0.9 micrometer thick egg envelope and, attached to that, a peripheral jelly layer about 3 micrometers thick. Before fertilization, the sperm undergoes the acrosome reaction and binds to the egg envelope. As part of a study of the induction of the acrosome reaction...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1985-03-01 00:00:00
abstract：:Mammalian Delta9 stearoyl-CoA desaturase 1 (SCD1) is a key enzyme in the biosynthesis of mono-unsaturated fatty acids in the endoplasmic reticulum (ER). It is a short-lived multispanning ER membrane protein, reported to be degraded by the ubiquitin-proteasome-independent pathway. We have examined SCD1 protein degradat...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02951
更新日期：2006-06-01 00:00:00
abstract：:The actin-dependent sensory and response elements of stromal cells that are involved in mechanical signal transduction are poorly understood. To study mechanotransduction we have described previously a collagen-magnetic bead model in which application of well-defined forces to integrins induces an immediate (< 1 secon...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1997-01-01 00:00:00
abstract：:Coronins are conserved F-actin-binding proteins that are important for motility and actin dynamics. Unlike type I coronins, coronin 2A localizes to stress fibers and some focal adhesions, and is excluded from the leading edge. Depletion of coronin 2A in MTLn3 cells decreases cell motility and turnover of focal adhesio...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.051482
更新日期：2009-09-01 00:00:00
abstract：:Pin1/Ess1p is a highly conserved WW domain-containing peptidyl-prolyl isomerase (PPIase); its WW domain binds specifically to phospho-Ser/Thr-Pro sequences and its catalytic domain isomerizes phospho-Ser/Thr-Pro bonds. Pin1 PPIase activity can alter protein conformation in a phosphorylation-dependent manner and/or pro...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2001-10-01 00:00:00
abstract：:Mitosis involves considerable membrane remodelling and vesicular trafficking to generate two independent cells. Consequently, endocytosis and endocytic proteins are required for efficient mitotic progression and completion. Several endocytic proteins also participate in mitosis in an endocytosis-independent manner. He...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.105981
更新日期：2012-09-15 00:00:00
abstract：:Multinucleated giant cells, characteristic of granulomatous infections, originate from the fusion of macrophages. Using an antibody screening strategy we found that the scavenger receptor CD36 participates in macrophage fusion induced by the cytokines IL-4 and GM-CSF. Our results demonstrate that exposure of phosphati...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.037200
更新日期：2009-02-15 00:00:00
abstract：:The C terminus of the tubulin alpha-subunit of most eukaryotic cells undergoes a cycle of tyrosination and detyrosination using two specific enzymes, a tubulin tyrosine ligase (TTL) and a tubulin carboxypeptidase. Although this enzyme cycle is conserved in evolution and exhibits rapid turnover, the meaning of this mod...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1998-01-01 00:00:00
abstract：:The process of regulated exocytosis is defined by the Ca2+-triggered fusion of two apposed membranes, enabling the release of vesicular contents. This fusion step involves a number of energetically complex steps and requires both protein and lipid membrane components. The role of cholesterol has been investigated usin...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02601
更新日期：2005-10-15 00:00:00
abstract：:Hybrid cell lines between normal rat embryo fibroblasts and TA3B mouse tumour cells, or between TA3B and BI hamster sarcoma cells, have been examined for the expression of the cell surface large external-transformation-sensitive (LETS) protein and the organization of microfilament bundles. LETS protein was detected by...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1978-10-01 00:00:00
abstract：:The mitotic spindle has long been recognized to play an essential role in determining the position of the cleavage furrow during cell division, however little is known about the mechanisms involved in this process. One attractive hypothesis is that signals from the spindle may function to induce reorganization of cort...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1996-08-01 00:00:00
abstract：:Position-effect variegation results from mosaic silencing by chromosomal rearrangements juxtaposing euchromatin genes next to pericentric heterochromatin. An increase in the amounts of the heterochromatin-associated Su(var)3-7 and HP1 proteins augments silencing. Using the yeast two-hybrid protein interaction trap sys...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2000-12-01 00:00:00
abstract：:The family of integrin transmembrane receptors is essential for the normal function of multicellular organisms by facilitating cell-extracellular matrix adhesion. The vitronectin-binding integrin αVβ5 localizes to focal adhesions (FAs) as well as poorly characterized flat clathrin lattices (FCLs). Here, we show that, ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.221317
更新日期：2018-11-05 00:00:00
abstract：:By an improved freeze-fracture device, a number of double replicas were obtained from the rod disk membranes of the carp retina for investigation of complementary, continuing, and transitional relationships between fracture faces. Some separate particles found along the smooth edge bordering on the adjacent interdisk ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1980-04-01 00:00:00
