Abstract：
:Sea urchin coelomocytes undergo an inducible structural transformation from petalloid to filopodial form during the 'clotting' response in sea urchins. Using a petalloid coelomocyte model, stimulated coelomocytes exhibited bidirectional particle/vesicle motility with a broad distribution of velocities, ranging from 0.02 to 0.12 microns s-1 in the outward bound direction. Coelomocytes treated with the microtubule-disrupting drug, nocodazole, continued to exhibit outward particle/vesicle movements along linear paths with an average velocity of 0.028 +/- 0.006 microns s-1. We partially purified a 110 kDa polypeptide possessing K+EDTA-, Ca2(+)-, Mg2(+)- and F-actin-activated Mg(2+)-ATPase activities characteristic of myosin-like motor proteins. The 110 kDa protein immuno-crossreacted with both affinity-purified, anti-brush border unconventional myosin-I polyclonal antibodies and anti-Acanthamoeba myosin head monoclonal antibodies. By indirect immunofluorescence, the 110 kDa unconventional myosin was localized to clusters of particles/vesicles within the perinuclear region of unstimulated coelomocytes, an area containing numerous mitochondria, acidic, lysosomal and Golgi organelles. Indirect immunofluorescence of partially transformed and filopodial coelomocytes detected a diminution of perinuclear staining with a concomitant appearance of stained linear arrays of particles/vesicles, enhanced staining of peripheral lamellae, and staining of the entire length of the filopodia. Subfractionation of unstimulated coelomocyte homogenates on linear sucrose gradients identified distinct peaks of ATPase activity associated with fractions containing conventional and 110 kDa unconventional myosin. Unconventional myosin-containing fractions were found to have numerous particles that stained with anti-brush border unconventional myosin-I antibodies and the lipophilic dye, DiOC6. Thus, coelomocytes demonstrate activatable movements of particles/vesicles in cells devoid of microtubules and possess an unconventional myosin, which may be the motor protein driving particle/vesicle translocation.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
D'Andrea L,Danon MA,Sgourdas GP,Bonder EMsubject
Has Abstractpub_date
1994-08-01 00:00:00pages
2081-94eissn
0021-9533issn
1477-9137journal_volume
107 ( Pt 8)pub_type
杂志文章abstract：:Protein with tau-like repeats (PTL-1) is the sole Caenorhabditis elegans homolog of tau and MAP2, which are members of the mammalian family of microtubule-associated proteins (MAPs). In mammalian neurons, tau and MAP2 are segregated, with tau being mainly localised to the axon and MAP2 mainly to the dendrite. In parti...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.jcs124404
更新日期：2013-05-01 00:00:00
abstract：:The fate of concanavalin A (Con A) bound to normal and enucleated L cells was followed at the ultrastructural level over a 20-h period. In both enucleates and normal cells the Con A is seen to be distributed in a uniform manner over the entire cell surface following a 30-min pulse with a low concentration of Con A. In...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1976-12-01 00:00:00
abstract：:Elementary Ca(2+) signals, such as "Ca(2+) puffs", which arise from the activation of inositol 1,4,5-trisphosphate receptors, are building blocks for local and global Ca(2+) signalling. We characterized Ca(2+) puffs in six cell types that expressed differing ratios of the three inositol 1,4,5-trisphosphate receptor is...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2001-11-01 00:00:00
abstract：:The interaction of the non-receptor tyrosine kinase, Src, with the cytoskeleton of adhesion sites was studied in nerve growth cones isolated from fetal rat brain. Of particular interest was the role of protein tyrosine phosphatases in the regulation of Src-cytoskeleton binding. Growth cones were found to contain a hig...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1998-08-01 00:00:00
abstract：:Nascent transcripts in permeabilized HeLa cells were elongated by approximately 30-2,000 nucleotides in Br-UTP or biotin-14-CTP, before incorporation sites were immunolabelled either pre- or post-embedding, and visualized by light or electron microscopy. Analogues were concentrated in approximately 2,100 (range 2,000-...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1996-06-01 00:00:00
abstract：:To enhance our understanding of the function(s) of gamma-tubulin-complex proteins (GCPs), we identified and analyzed the functions of the Aspergillus nidulans homologs of GCP2-GCP6 (here designated GCPB-GCBF). The gamma-tubulin small complex (gamma-TuSC) components, gamma-tubulin, GCPB and GCPC, are essential for viab...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.059196
更新日期：2009-11-15 00:00:00
abstract：:The PX domain, which until recently was an orphan domain, has emerged as the latest member of the phosphoinositide-binding module superfamily. Structural studies have revealed that it has a novel fold and identified key residues that interact with the bound phosphoinositide, enabling some prediction of phosphoinositid...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：
更新日期：2002-03-15 00:00:00
abstract：:Here, we identify a role for the matrilin-2 (Matn2) extracellular matrix protein in controlling the early stages of myogenic differentiation. We observed Matn2 deposition around proliferating, differentiating and fusing myoblasts in culture and during muscle regeneration in vivo. Silencing of Matn2 delayed the express...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.141556
更新日期：2014-08-01 00:00:00
abstract：:Autophagy requires the formation of membrane vesicles, known as autophagosomes, that engulf cellular cargoes and subsequently recruit lysosomal hydrolases for the degradation of their contents. A number of autophagy-related proteins act to mediate the de novo biogenesis of autophagosomes and vesicular trafficking even...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.249227
更新日期：2020-10-30 00:00:00
abstract：:Directed cell migration results from the polarization of the cellular motile apparatus by integration of extracellular signals, which are presented in a three-dimensional, spatiotemporal manner in living organisms. To investigate the mechanism underlying the highly polarized and directional nature of migration in vivo...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03080
更新日期：2006-09-01 00:00:00
abstract：:Recent biochemical and molecular approaches have begun to establish the protein interactions that lead to desmosome assembly. To determine whether these associations occur in native desmosomes we have performed ultrastructural localisation of specific domains of the major desmosomal components and have used the result...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1999-12-01 00:00:00
abstract：:When human cells enter S-phase, overlapping differential inhibitory mechanisms downregulate the replication licensing factors ORC1, CDC6 and Cdt1. Such regulation prevents re-replication so that deregulation of any individual factor alone would not be expected to induce overt re-replication. However, this has been cha...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.041889
更新日期：2009-04-15 00:00:00
abstract：:The DNA content of isolated micronuclei, differentiating macronuclei (macronuclear Anlagen), and adult macronuclei of Loxodes magnus was measured cytofluorimetrically in preparations stained with a Schiff-type reagent, auramine-SO2, following hydrochloric acid hydrolysis. The DNA content of the youngest macronuclear 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：:Fas ligand (FasL), a potent mediator of apoptosis expressed by CTL and NK cells, is sorted into the inner vesicles of secretory lysosomes for release via exosome-like vesicles. Previous studies identified a proline-rich domain in the cytoplasmic tail required for sorting FasL to secretory lysosomes, but the mechanisms...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03315
更新日期：2007-01-01 00:00:00
abstract：:Fibroblast migration is an integral component of biological processes such as wound healing and embryogenesis. Previous experiments examining fibroblast locomotion from tissue explants have shown that migrating fibroblasts lack, or contain only transient, focal adhesions (focal contacts). Focal adhesions are specializ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1993-06-01 00:00:00
abstract：:In order to determine whether fibronexus morphogenesis is involved in the establishment of more normal cellular morphology and substrate adhesion patterns in Nil/HSV transformed fibroblasts induced by treatment with exogenous fibronectin (FN), this system was studied with electron microscopy (EM), immunocytochemistry,...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1982-08-01 00:00:00
abstract：:Rac1 has a crucial role in epidermal growth factor (EGF)-induced membrane ruffling, lamellipodial protrusion, and cell migration. Several guanine nucleotide exchange factors (GEFs) including Sos1, Sos2, Tiam1 and Vav2 have been shown to transduce the growth signal from the EGF receptor to Rac1. To clarify the role of ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.028647
更新日期：2008-08-15 00:00:00
abstract：:Cancer cells thrive when challenged with proteotoxic stress by inducing components of the protein folding, proteasome, autophagy and unfolded protein response (UPR) pathways. Consequently, specific molecular chaperones have been validated as targets for anti-cancer therapies. For example, inhibition of Hsp70 family pr...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.217760
更新日期：2018-09-05 00:00:00
abstract：:Cells are internally organized into compartmentalized organelles that execute specialized functions. To understand the functions of individual organelles and their regulations, it is critical to resolve the compositions of individual organelles, which relies on a rapid and efficient isolation method for specific organ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.235390
更新日期：2019-12-13 00:00:00
abstract：:Arf GTPases regulate both the morphological and protein sorting events that are essential for membrane trafficking. Guanine nucleotide exchange factors (GEFs) specific for Arf proteins determine when and where Arf GTPases will be activated in cells. The yeast Gea2p Arf GEF is a member of an evolutionarily conserved fa...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00896
更新日期：2004-02-15 00:00:00
abstract：:The Rho-family proteins make up a major branch of the Ras superfamily of small GTPases. To date, 22 human genes encoding at least 25 proteins have been described. The best known 'classical' members are RhoA, Rac1 and Cdc42. Highly related isoforms of these three proteins have not been studied as intensively, in part b...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.01118
更新日期：2004-03-15 00:00:00
abstract：:Cells undergo a variety of physiological processes, including division, migration and differentiation, under the influence of endogenous electrical cues, which are generated physiologically and pathologically in the extracellular and sometimes intracellular spaces. These signals are transduced to regulate cell behavio...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.023564
更新日期：2009-12-01 00:00:00
abstract：:Caveolins are membrane proteins that are the major coat proteins of caveolae, specialized lipid rafts in the plasma membrane that serve as scaffolding sites for many signaling complexes. Among the many signaling molecules associated with caveolins are the Src tyrosine kinases, whose activation regulates numerous cellu...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00806
更新日期：2003-12-01 00:00:00
abstract：:The cellular microenvironment, characterized by an extracellular matrix (ECM), played an essential role in the transition from unicellularity to multicellularity in animals (metazoans), and in the subsequent evolution of diverse animal tissues and organs. A major ECM component are members of the collagen superfamily -...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.203950
更新日期：2018-04-09 00:00:00
abstract：:Diploid yeast, like most eukaryotes, can undergo meiotic differentiation to form haploid gametes. Meiotic differentiation and cell growth (proliferation) are mutually exclusive programs, and in yeast the switch between growth and meiosis is controlled by nutritional signals. The signaling pathways that mediate nutriti...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.00460
更新日期：2003-06-01 00:00:00
abstract：:Members of the PKC superfamily have been implicated in various migratory models and in particular in spatially restricted processes. However, defining the precise local events that underlie the PKC-dependent processes is constrained by the unspecific nature of interventions. Here we address this problem in relation to...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.062299
更新日期：2010-08-15 00:00:00
abstract：:Euglena gracilis is a suitable model system to investigate the role of zinc in the process of cell division. In zinc-deficient organisms there is a characteristic arrest of cellular proliferation, the DNA content of the cells doubles, whereas RNA and protein contents decrease. The present investigations include the gr...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1975-01-01 00:00:00
abstract：:In metazoans, cyclin-dependent kinase 7 (CDK7) has essential roles in both the cell-division cycle and transcription, as a CDK-activating kinase (CAK) and as a component of the general transcription factor TFIIH, respectively. Controversy over its double duty has been resolved, but questions remain. First, how does CD...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.02718
更新日期：2005-11-15 00:00:00
abstract：:Vaccinia virus B1 kinase plays a key role in viral DNA replication. The homologous mammalian vaccinia-related kinases (VRKs) are also implicated in the regulation of DNA replication, although direct evidence remains elusive. Here we show that VRK1 regulates cell cycle progression in the DNA replication period by induc...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.026757
更新日期：2008-09-15 00:00:00
abstract：:p97 (CDC-48 in Caenorhabditis elegans) is a ubiquitin-selective AAA (ATPases associated with diverse cellular activities) chaperone and its key function is to disassemble protein complexes. p97 functions in diverse cellular processes including endoplasmic reticulum (ER)-associated degradation, membrane fusion, and mei...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.052415
更新日期：2009-10-15 00:00:00
