Abstract:
:Lens fiber cells are transparent, highly elongated, epithelial cells. Because of their unusual length these cells represent a novel model system to investigate aspects of epithelial cell polarity. In this study, we examined the fiber cell basal membrane complex (BMC). The BMC anchors fiber cells to the lens capsule and facilitates their migration across the capsule. Confocal microscopy revealed that bundled actin filaments converge beneath the center of each BMC and insert into the lateral membrane at points enriched in N-cadherin. Two other contractile proteins, caldesmon and myosin, were enriched in the BMC, co-localizing with f-actin bundles. The actin/N-cadherin complex formed a hexagonal lattice, cradling the posterior face of the lens. Removal of the capsule caused the tips of the fiber cells to break off, remaining attached to the stripped capsule. This provided a method for assaying cell adhesion and purifying BMC components. Fiber cell adhesion required Mg2+ and/or Ca2+ and was disrupted by incubation with beta1 integrin antibody. BMC proteins were compared with samples from the neighboring lateral membrane. Although some components were common to both samples, others were unique to the BMC. Furthermore, some lateral membrane proteins, most notably lens major intrinsic protein (MIP), were excluded from the BMC. Western blotting of BMC preparations identified several structural proteins originally found in focal adhesions and two kinases, FAK and MLCK, previously undescribed in the lens. These data suggest that the BMC constitutes a distinct membrane domain in the lens. The structural organization of the BMC suggests a role in shaping the posterior lens face and hence the refractive properties of the eye.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Bassnett S,Missey H,Vucemilo Isubject
Has Abstractpub_date
1999-07-01 00:00:00pages
2155-65eissn
0021-9533issn
1477-9137journal_volume
112 ( Pt 13)pub_type
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journal_title:Journal of cell science
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journal_title:Journal of cell science
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abstract::Hypoxia-inducible factor-1 (HIF-1) is a master regulator of mammalian oxygen homeostasis. HIF-1 consists of two subunits, HIF-1alpha and the aryl hydrocarbon receptor nuclear translocator (ARNT). Whereas hypoxia prevents proteasomal degradation of HIF-1alpha, ARNT expression is thought to be oxygen-independent. We and...
journal_title:Journal of cell science
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abstract::Circus movements, which involve the circumferential rotation of a hyaline cytoplasmic protrusion, occur in cells obtained by EDTA dissociation of gastrula-stage Xenopus laevis embryos. Only a few dissociated blastula-stage cells show circus movements, more early gastrula-stage cells show them, and nearly all late gast...
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abstract::When subjected to uni-axial cyclic stretch (120% in length, 1 Hz), fibroblasts (3Y1) aligned perpendicular to the stretch axis in a couple of hours. Concomitantly with this orienting response, protein tyrosine phosphorylation of cellular proteins (molecular masses of approximately 70 kDa and 120-130 kDa) increased and...
journal_title:Journal of cell science
pub_type: 杂志文章
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更新日期:1999-05-01 00:00:00
abstract::The mammary epithelium is composed of a luminal epithelium and a basal layer containing myoepithelial cells and undifferentiated precursors. Basal cells express specific protein markers, such as keratin 14 (K14) and P-cadherin. To study the factors that regulate the basal mammary epithelial cell phenotype, we have est...
journal_title:Journal of cell science
pub_type: 杂志文章
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更新日期:1999-04-01 00:00:00
abstract::Asymmetric distribution of messenger RNAs is a widespread mechanism to localize synthesis of specific protein to distinct sites in the cell. Although not proven yet there is considerable evidence that mRNA localisation is an active process that depends on the activity of cytoskeletal motor proteins. To date, the only ...
journal_title:Journal of cell science
pub_type: 杂志文章
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更新日期:1999-05-01 00:00:00
abstract::The cadherin/catenin complex mediates Ca2+-dependent cell-cell interactions that are essential for normal developmental processes. It has been proposed that sorting of cells during embryonic development is due, at least in part, to expression of different cadherin family members or to expression of differing levels of...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-05-01 00:00:00
abstract::ErbB2 (HER2, Neu), a member of the epidermal growth factor (EGF) receptor tyrosine kinase family, is often overexpressed in breast cancer and other malignancies. ErbB2 homodimerizes but also presents as a common auxiliary subunit of the EGF and heregulin receptors (erbB1 or EGFR; and erbB3-4, respectively), with which...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-06-01 00:00:00
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journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-06-01 00:00:00
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journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-06-01 00:00:00
abstract::PECAM-1 (CD31) is a highly abundant cell surface glycoprotein expressed on haemopoietic and endothelial cells. As well as mediating homophilic (PECAM-1/PECAM-1) adhesion, PECAM-1 can also bind the integrin alphavbeta3. Both PECAM-1 and alphavbeta3 have been shown to have roles in regulating angiogenesis, endothelial t...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-06-01 00:00:00
abstract::Nuclear pore complexes (NPCs) are extremely elaborate structures that mediate the bidirectional movement of macromolecules between the nucleus and cytoplasm. With a mass of about 125 MDa, NPCs are thought to be composed of 50 or more distinct protein subunits, each present in multiple copies. During mitosis in higher ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-07-01 00:00:00
abstract::Transfer of passive immunity from mother to the fetus or newborn involves the transport of IgG across several epithelia. Depending on the species, IgG is transported prenatally across the placenta and yolk sac or is absorbed from colostrum and milk by the small intestine of the suckling newborn. In both cases apical t...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-07-01 00:00:00
abstract::Abnormal proliferation signals, driven by cellular or viral oncogenes, can result in the induction of apoptosis under sub-optimal cell growth conditions. The tumor suppressor p53 plays a central role in mediating oncogene-induced apoptosis, therefore transformed cells lacking p53 are generally resistant to apoptosis-p...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-07-01 00:00:00
abstract::The monoclonal antibody MPM-2 recognizes a subset of M phase phosphoproteins in a phosphorylation-dependent manner. It is believed that phosphorylation at MPM-2 antigenic sites could regulate mitotic events since most of the MPM-2 antigens identified to date have M phase functions. In addition, many of these proteins ...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::Downstream signaling triggered by the binding of fibroblast growth factor-2 (FGF2) to its tyrosine-kinase receptors involves the activation of mitogen-activated protein kinase kinase (MEK) with consequent phosphorylation of extracellular signal-regulated kinases (ERKs). Here we demonstrate that FGF2 induces ERK1/2 act...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::The L1 adhesion molecule is an approx. 200-220 kDa type I membrane glycoprotein belonging to the immunoglobulin (Ig) superfamily. L1 can bind in a homotypic fashion and was shown to support integrin-mediated binding via RGDs in the 6th Ig-like domain. In addition to its cell-surface expression, L1 can occur in the ext...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::Beta1,4-Galactosyltransferase I (GalT I) is localized on the leading lamellipodia of migrating cells, where it associates with the cytoskeleton and facilitates cell spreading and migration on basal lamina matrices. It has previously been reported that a variety of highly metastatic murine and human cell lines are char...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::The discovery of glycosylphosphatidylinositol (GPI) membrane anchors has had a significant impact on several areas of eukaryote cell biology. Studies of the African trypanosome, which expresses a dense surface coat of GPI-anchored variant surface glycoprotein, have played important roles in establishing the general st...
journal_title:Journal of cell science
pub_type: 杂志文章,评审
doi:
更新日期:1999-09-01 00:00:00
abstract::Single, murine embryonic stem cell-derived early stage cardiomyocytes dissociated from embryoid bodies expressed two inward rectifier K(+) channels, I(K1) and the ATP dependent K(+) current. I(K1) exhibited low density in early stage cardiomyocytes, but increased significantly in late stage cells. In contrast, the ATP...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-09-01 00:00:00
abstract::The flagellar pocket of African trypanosomes is a critical sorting station for protein and membrane trafficking, and is considered to be an Achilles' heel of this deadly pathogen. Although several proteins, including receptors for host-derived growth factors, are targeted specifically to the flagellar pocket, the sign...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-09-01 00:00:00
abstract::The behavior of chimeric proteins consisting of A-type lamins and green fluorescent protein (GFP) was studied to investigate the localization and dynamics of nuclear lamins in living cells. Cell line CHO-K1 was transfected with cDNA constructs encoding fusion proteins of lamin A-GFP, lamin Adelta10-GFP, or lamin C-GFP...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract::Schizosaccharomyces pombe rho1(+) is required for maintenance of cell integrity and polarization of the actin cytoskeleton. However, no other effector besides the (1,3)beta-D-glucan synthase enzyme has been identified in S. pombe. We have further investigated if rho1(+ )signalling could be also mediated by the two pro...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract::The CAP (cyclase-associated protein) homologue of Dictyostelium discoideum is a phosphatidylinositol 4,5-bisphosphate (PIP(2)) regulated G-actin sequestering protein which is present in the cytosol and shows enrichment at plasma membrane regions. It is composed of two domains separated by a proline rich stretch. The s...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract::PTP-BL is a cytosolic multidomain protein tyrosine phosphatase that shares homologies with several submembranous and tumor suppressor proteins. Here we show, by transient expression of modular protein domains of PTP-BL in epithelial MDCK cells, that the presence of a FERM domain in the protein is both necessary and su...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract::Ribonucleoprotein particles (RNPs) are thought to be key players in somato-dendritic sorting of mRNAs in CNS neurons and are implicated in activity-directed neuronal remodeling. Here, we use reporter constructs and gel mobility shift assays to show that the testis brain RNA-binding protein (TB-RBP) associates with mRN...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract::We examined cytoskeleton-associated forms of NF proteins during axonal neuritogenesis in cultured dorsal root ganglion (DRG) neurons and NB2a/d1 neuroblastoma. In addition to filamentous immunoreactivity, we observed punctate NF immunoreactivity throughout perikarya and neurites. Immuno-electron microscopy revealed th...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract::We reported recently on the intracellular localisation of the hyaluronan receptor RHAMM/IHABP in human cancer cells. Here we describe the colocalisation of RHAMM/IHABP proteins with microtubules, both in interphase and dividing cells, suggesting that RHAMM/IHABP represents a novel member of the family of microtubule-a...
journal_title:Journal of cell science
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00