Abstract：
:Earlier reports have indicated that the pollen of Eucalyptus is mechanically robust and unusually resistant to the osmotic stress imposed by immersion in water. We have investigated some of the features of the germination mechanism in the pollen of E. rhodantha with a view to clarifying the role of pollen-wall specializations in determining this resistance. Cultured in vitro, the pollen showed erratic germination, with a scatter of germination times up to 24 h. This was associated with variation between individual grains in the rate of hydration and dispersal of the pectins of the oncus, the thickened outer component of the intine present at each aperture. The oncus is itself differentiated, with a refractive outer layer lying within a sporopollenin operculum and itself overlying the protein-bearing layer of the intine. The outer layer, interpreted as a compacted pectin, undergoes only slow dissolution in aqueous media after the lifting of the operculum, and it is this that apparently protects the grain from the effects of short-term osmotic stress. The rate of dissolution varies between grains, possibly as a consequence of minor differences in developmental rate in the final stages of differentiation in the anther, and this contributes to the wider scatter of germination times. The dehydrated pollen gave one-third of the potential germination after 24 h exposure to 60 degrees C, and a small proportion survived 24 h at 70 degrees C. This degree of heat tolerance must primarily reflect properties of the protoplast of the vegetative cell, not examined in the present study; but the wall specializations may well provide a guard against extreme desiccation, and it is noteworthy that the function of the germination mechanism is not prejudiced by exposure to high temperatures.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Heslop-Harrison J,Heslop-Harrison Ysubject
Has Abstractpub_date
1985-02-01 00:00:00pages
135-57eissn
0021-9533issn
1477-9137journal_volume
73pub_type
杂志文章abstract：:Prox1 is a master regulator for the development of lymphatic vasculature and the induction of lymphangiogenesis. In this study, we identified Prox1 as a new target for small ubiquitin-like modifier 1 (SUMO-1). Lysine 556 (K556) was found to be the major sumoylation site for Prox1 in vitro and in vivo. Mutation of this...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.050005
更新日期：2009-09-15 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：:Nopp44/46 is a phosphoprotein of the protozoan parasite Trypanosoma brucei that is localized to the nucleolus. Based on the primary sequence, Nopp44/46 appears to be a protein composed of distinct domains. This communication describes the relationship of these domains to the known functional interactions of the molecu...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1998-09-01 00:00:00
abstract：:Histone proteins are essential for chromatin formation, and histone gene expression is coupled to DNA synthesis. In metazoans, the histone RNA binding protein HBP/SLBP is involved in post-transcriptional control of histone gene expression. In vitro assays have demonstrated that human HBP/SLBP is involved in histone mR...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01523
更新日期：2004-12-01 00:00:00
abstract：:BMP-dependent patterning in the Drosophila melanogaster wing imaginal disc serves as a paradigm to understand how morphogens specify cell fates. The observed profile of the transcriptional response to the graded signal of BMP relies upon two counter-active gradients of pMad and Brinker (Brk). This patterning model is ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.110569
更新日期：2012-12-01 00:00:00
abstract：:The atomic force microscope (AFM) was used to directly image hippocampal neurons and glia. Using chemically fixed and living cells it was possible to reconstruct three-dimensional cell structure and detect sub-cellular features such as the nucleus, mitochondria and filaments. By repeatedly scanning a single living cel...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1993-02-01 00:00:00
abstract：:Junctional adhesion molecules (JAMs) are members of an immunoglobulin subfamily expressed by leukocytes and platelets as well as by epithelial and endothelial cells, in which they localize to cell-cell contacts and are specifically enriched at tight junctions. The recent identification of extracellular ligands and int...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
doi：10.1242/jcs.00930
更新日期：2004-01-01 00:00:00
abstract：:Signalling by target-derived neurotrophins is essential for the correct development of the nervous system and its maintenance throughout life. Several aspects concerning the lifecycle of neurotrophins and their receptors have been characterised over the years, including the formation, endocytosis and trafficking of si...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.242412
更新日期：2020-03-30 00:00:00
abstract：:Tetrahymena thermophila swims by the coordinated beating of hundreds of cilia that cover its body. It has been proposed that the outer arm dyneins of the ciliary axoneme control beat frequency, whereas the inner arm dyneins control waveform. To test the role of one of these inner arms, dynein heavy chain 7 protein (Dy...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.007369
更新日期：2007-09-01 00:00:00
abstract：:Previously, we documented the role of the programmed death-1 (PD-1, also known as PDCD1) pathway in macrophage apoptosis and the downregulation of this signaling during infection by the intra-macrophage parasite Leishmania donovani However, we also found that, during the late phase of infection, PD-1 expression was si...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.226274
更新日期：2019-05-02 00:00:00
abstract：:Mitochondria are dynamic organelles that undergo regulated fission and fusion events that are essential to maintain metabolic stability. We previously demonstrated that the mitochondrial fission GTPase DRP1 is a substrate for SUMOylation. To further understand how SUMOylation impacts mitochondrial function, we searche...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03418
更新日期：2007-04-01 00:00:00
abstract：:MOR1, the Arabidopsis thaliana homologue of the Xenopus microtubule-associated protein MAP215, is required for spatial organization of the acentrosomal microtubule arrays of plant cells. To determine how loss of MOR1 function affects microtubule dynamics, we compared various parameters of microtubule dynamics in the t...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.039065
更新日期：2008-12-15 00:00:00
abstract：:HEK293 cells expressing wild-type CXCR2 recruit PH-Akt-GFP to the leading edge of the cell in response to chemokine. However, in cells expressing mutant CXCR2 defective in AP-2 and HIP binding, i.e. with a mutation in the LLKIL motif, PH-Akt-GFP does not localize to the leading edge in response to ligand. Inhibition o...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01398
更新日期：2004-11-01 00:00:00
abstract：:Recent evidence suggests that organization of the extracellular matrix (ECM) into aligned fibrils or fibril-like ECM topographies promotes rapid migration in fibroblasts. However, the mechanisms of cell migration that are altered by these changes in micro-environmental topography remain unknown. Here, using 1D fibrill...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.098806
更新日期：2012-05-01 00:00:00
abstract：:Gap junctions (GJs) assembled from connexin (Cx) proteins allow direct cell-cell communication. While phosphorylation is known to regulate multiple GJ functions, much less is known about the role of ubiquitin in these processes. Using ubiquitylation-type-specific antibodies and Cx43 lysine-to-arginine mutants we show ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.204321
更新日期：2018-08-09 00:00:00
abstract：:The neuroprotective role of carbon monoxide (CO) has been studied in a cell-autonomous mode. Herein, a new concept is disclosed - CO affects astrocyte-neuron communication in a paracrine manner to promote neuroprotection. Neuronal survival was assessed when co-cultured with astrocytes that had been pre-treated or not ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.187260
更新日期：2016-08-15 00:00:00
abstract：:MAP1B is a developmentally regulated microtubule-associated phosphoprotein that regulates microtubule dynamics in growing axons and growth cones. We used mass spectrometry to map 28 phosphorylation sites on MAP1B, and selected for further study a putative primed GSK3 beta site and compared it with two nonprimed GSK3 b...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.040162
更新日期：2009-07-15 00:00:00
abstract：:Ca2+ is a second messenger in many physiological and phytopathological processes. Peroxisomes are subcellular compartments with an active oxidative and nitrosative metabolism. Previous studies have demonstrated that peroxisomal nitric oxide (NO) generation is dependent on Ca2+ and calmodulin (CaM). Here, we used Arabi...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.201467
更新日期：2018-01-29 00:00:00
abstract：:The tumor suppressor p53 is activated in response to many forms of cellular stress leading to cell cycle arrest, senescence or apoptosis. Appropriate sub-cellular localization is essential for modulating p53 function. We recently showed that p53 localizes to the nucleolus after proteasome inhibition with MG132 and thi...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.030098
更新日期：2008-12-15 00:00:00
abstract：:U937 human promonocytic leukemia cells express PKC isozymes beta 1, beta 2, epsilon and zeta. Indirect immunocytofluorescence using affinity-purified PKC-specific antibodies indicates that each of the endogenous PKC isozymes in U937 cells display a unique compartmentalization within the intact cell. PKC-beta 1 is dist...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1995-03-01 00:00:00
abstract：:Ryanodine receptors (RyRs) are expressed on the endoplasmic reticulum of many cells, where they form intracellular Ca2+-release channels that participate in the generation of intracellular Ca2+ signals. Here we report studies on the intracellular localisation and functional properties of transfected RyR1 or RyR3 chann...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：2002-06-15 00:00:00
abstract：:Atomic force microscopy (AFM) was used to probe topology, conformational changes and initial substrate-carrier interactions of Na+-glucose co-transporter (SGLT1) in living cells on a single-molecule level. By scanning SGLT1-transfected Chinese hamster ovary (CHO) cells with AFM tips carrying an epitope-specific antibo...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03035
更新日期：2006-07-15 00:00:00
abstract：:Tau is a neuronal microtubule-associated protein that appears to function in the formation and maintenance of axons by influencing microtubule organisation. Tau is a phosphoprotein and is more heavily phosphorylated in fetal than in adult brain, and is also hyperphosphorylated in Alzheimer's disease where it forms the...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1996-06-01 00:00:00
abstract：:Long noncoding RNAs (lncRNAs) have emerged as important regulators of cancer progression. Abnormal sialylation leads to renal cell carcinoma (RCC) malignancy. However, the mechanism by which the lncRNA maternally expressed gene 3 (MEG3) mediates RCC progression by regulating ST3Gal1 transcription and EGFR sialylation ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.244020
更新日期：2020-08-25 00:00:00
abstract：:Motile eukaryotic flagella beat through coordinated activity of dynein motor proteins; however, the mechanisms of dynein coordination and regulation are incompletely understood. The inner dynein arm (IDA) f complex (also known as the I1 complex), and the tether and tether head (T/TH) complex are thought to be key regu...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.239855
更新日期：2020-01-23 00:00:00
abstract：:The serine/threonine protein phosphatase-1 (PP1) complex is a key regulator of the cell cycle. However, the redundancy of PP1 isoforms and the lack of specific inhibitors have hampered studies on the global role of PP1 in cell cycle progression in vertebrates. Here, we show that the overexpression of nuclear inhibitor...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.175588
更新日期：2015-12-15 00:00:00
abstract：:Endothelial cells (ECs) sense shear stress and transduce blood flow information into functional responses that play important roles in vascular homeostasis and pathophysiology. A unique feature of shear-stress-sensing is the involvement of many different types of membrane-bound molecules, including receptors, ion chan...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.119628
更新日期：2013-03-01 00:00:00
abstract：:Analysis by double-label indirect immunofluorescence of PtK1 and HeLa cells had previously demonstrated that prosome* antigens form networks that superimpose on those of the intermediate filaments of the cytokeratin type. We show here that in PtK1 cells various prosomal antigens also reside to a variable extent on int...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1994-03-01 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：:Trypsin digestion of demembranated fowl spermatozoa caused a longitudinal splitting of the distal part of the axoneme. The resulting strands, consisting of groups of doublet microtubules, formed left-handed helices. On the evidence of electron micrographs, the digestion had caused the loss of dynein arms from the oute...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
