Abstract：
:A plasmalemmal Na(+)-Ca2+ exchange mechanism is an important electrogenic determinant of contractility in cardiac cells. As in other cell types, calcium influx by Na(+)-Ca2+ exchange is secondarily activated by cytoplasmic calcium and probably ATP, but these modulatory mechanisms are either absent or altered in isolated cardiac sarcolemmal vesicles. Involvement of a calcium-dependent protein kinase in exchange regulation has been suggested but not verified. Here I describe measurements of outward Na(+)-Ca2+ exchange current, corresponding to calcium influx, in giant excised sarcolemmal patches from guinea pig myocytes. The exchange current is stimulated by both calcium and Mg-ATP from the cytoplasmic face, evidently through separate mechanisms. Activation by cytoplasmic calcium takes place within seconds, is reversible, and does not require ATP. Stimulation by Mg-ATP reverses only slowly over greater than 10 min, or not at all. Unexpectedly, a substantial decrease in exchange current occurs during activation by cytoplasmic sodium, which seems to reflect an inactivation process rather than ion concentration changes or a 'first pass' exchange cycle. This apparent inactivation, and the modulations by cytoplasmic calcium and Mg-ATP, are all abolished by brief treatment of the cytoplasmic surface with chymotrypsin, leaving the exchanger in a maintained state of high activity. Therefore, limited proteolysis deregulates Na(+)-Ca2+ exchange and could contribute to the loss of secondary regulation of the exchange in isolated sarcolemmal vesicles.
journal_name
Naturejournal_title
Natureauthors
Hilgemann DWdoi
10.1038/344242a0subject
Has Abstractpub_date
1990-03-15 00:00:00pages
242-5issue
6263eissn
0028-0836issn
1476-4687journal_volume
344pub_type
杂志文章相关文献
NATURE文献大全abstract：:The Earth's mantle is isotopically heterogeneous on length scales ranging from centimetres to more than 10(4) kilometres. This heterogeneity originates from partial melt extraction and plate tectonic recycling, whereas stirring during mantle convection tends to reduce it. Here we show that mid-ocean ridge basalts from...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature04582
更新日期：2006-03-09 00:00:00
abstract：:Wild-type p53 protein has many properties consistent with its being the product of a tumour suppressor gene. Although the normal roles of tumour suppressor genes are still largely unknown, it seems that they could be involved in promoting cell differentiation as well as in mediating growth arrest by growth-inhibitory ...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/352345a0
更新日期：1991-07-25 00:00:00
abstract：:Graphene, or single-layered graphite, with its high crystallinity and interesting semimetal electronic properties, has emerged as an exciting two-dimensional material showing great promise for the fabrication of nanoscale devices. Thin, elongated strips of graphene that possess straight edges, termed graphene ribbons,...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature07872
更新日期：2009-04-16 00:00:00
abstract：:For the past couple of centuries the penchant for prediction has been prevalent at century turns. How much have evaluations of scientific discovery and predictions for future advancement changed since those of the science commentators at the end of the last century? ...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/35011581
更新日期：1999-12-02 00:00:00
abstract：:Sudden, large-scale and diffuse human migration can amplify localized outbreaks of disease into widespread epidemics1-4. Rapid and accurate tracking of aggregate population flows may therefore be epidemiologically informative. Here we use 11,478,484 counts of mobile phone data from individuals leaving or transiting th...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/s41586-020-2284-y
更新日期：2020-06-01 00:00:00
abstract：:Thewissen et al. describe new fossils from India that apparently support a phylogeny that places Cetacea (that is, whales, dolphins, porpoises) as the sister group to the extinct family Raoellidae, and Hippopotamidae as more closely related to pigs and peccaries (that is, Suina) than to cetaceans. However, our reanaly...
journal_title：Nature
pub_type： 评论,杂志文章
doi：10.1038/nature07776
更新日期：2009-03-19 00:00:00
abstract：:In this Review, the middle initial of author Kim M. Cobb was omitted. The original Review has been corrected online. ...
journal_title：Nature
pub_type： 杂志文章,已发布勘误
doi：10.1038/s41586-019-0994-9
更新日期：2019-03-01 00:00:00
abstract：:A mouse major histocompatibility antigen (H-2) gene, encoding a novel H-2Ld molecule lacking its intracytoplasmic domain, has been constructed and introduced into mouse L-cells. The novel H-2 molecule is found on the surface of the transfected cells at the same level as L-cells transfected with the native H-2Ld gene. ...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/307432a0
更新日期：1984-02-02 00:00:00
abstract：:A brief account is provided of a meeting between federal officials and representatives of the Industrial Biotechnology Association (IBA), a consortium of companies concerned about the regulatory outlook for their industry. Current regulatory interest is focused on the Environmental Protection Agency, which has declar...
journal_title：Nature
pub_type： 新闻
doi：10.1038/305755a0
更新日期：1983-10-27 00:00:00
abstract：:This corrects the article DOI: 10.1038/nature22794. ...
journal_title：Nature
pub_type： 杂志文章,已发布勘误
doi：10.1038/nature25162
更新日期：2018-03-08 00:00:00
abstract：:An observer moving forwards through the environment experiences a radial pattern of image motion on each retina. Such patterns of optic flow are a potential source of information about the observer's rate of progress, direction of heading and time to reach objects that lie ahead. As the viewing distance changes there ...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/37359
更新日期：1997-12-04 00:00:00
abstract：:Hereditary persistance of fetal haemoglobin (HPFH) is a benign condition characterized by the production in adulthood of more than 1% fetal haemoglobin (HbF, alpha 2 gamma 2) in the absence of erythropoietic stress. Several genetic types have been discerned based on the level of HbF produced, the relative contribution...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/313325a0
更新日期：1985-01-24 00:00:00
abstract：:Macroscopic mechanical objects and electromagnetic degrees of freedom can couple to each other through radiation pressure. Optomechanical systems in which this coupling is sufficiently strong are predicted to show quantum effects and are a topic of considerable interest. Devices in this regime would offer new types of...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature06715
更新日期：2008-03-06 00:00:00
abstract：:The skin of mice contains dendritic epidermal cells carrying the Thy-1 antigen (Thy-1+ dEC) which express antigen receptors composed of the T-cell antigen receptor (TCR) gamma- and delta-chains. Although the role of the thymus in the generation of most T cells is well established, the involvement of the thymus in the ...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/344068a0
更新日期：1990-03-01 00:00:00
abstract：:The mechanism whereby eukaryotic pre-messenger RNAs are polyadenylated is unknown. Most models for polyadenylation invoke cleavage of precursor transcripts at the site of poly(A) addition followed by polymerization of A residues by poly(A) polymerase. Analysis of the sequences surrounding poly(A) addition sites has id...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/309179a0
更新日期：1984-05-10 00:00:00
abstract：:The Amazon rainforest plays a crucial role in the climate system, helping to drive atmospheric circulations in the tropics by absorbing energy and recycling about half of the rainfall that falls on it. This region (Amazonia) is also estimated to contain about one-tenth of the total carbon stored in land ecosystems, an...
journal_title：Nature
pub_type： 历史文章,杂志文章
doi：10.1038/nature06960
更新日期：2008-05-08 00:00:00
abstract：:The gene IL2RG encodes the gamma-chain of the interleukin-2 receptor and is mutated in patients with X-linked severe combined immune deficiency (X-SCID). Woods et al. report the development of thymus tumours in a mouse model of X-SCID after correction by lentiviral overexpression of IL2RG and claim that these were cau...
journal_title：Nature
pub_type： 评论,杂志文章
doi：10.1038/nature05218
更新日期：2006-09-21 00:00:00
abstract：:Retinal nerve fibres form an orderly map of visual space in several centres in the vertebrate brain. Such topographic maps are a common feature of central nervous system organization, yet the way in which they develop is poorly understood. Early nerve projections in the fetal and neonatal mammalian brain have been fou...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/301150a0
更新日期：1983-01-13 00:00:00
abstract：:Understanding the physical mechanisms behind the generation of ocean waves by wind has been a longstanding challenge. Previous studies have assumed that ocean waves induce fluctuations in velocity and pressure of the overlying air that are synchronized with the waves, and numerical models have supported this assumptio...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature01382
更新日期：2003-03-06 00:00:00
abstract：:Many galaxies are thought to have supermassive black holes at their centres-more than a million times the mass of the Sun. Measurements of stellar velocities and the discovery of variable X-ray emission have provided strong evidence in favour of such a black hole at the centre of the Milky Way, but have hitherto been ...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature01121
更新日期：2002-10-17 00:00:00
abstract：:The midbrain region periaqueductal grey (PAG) is rich in opioid receptors and endogenous opioids and is a major target of analgesic action in the central nervous system. It has been proposed that the analgesic effect of opioids on the PAG works by suppressing the inhibitory influence of the neurotransmitter GABA (gamm...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/37610
更新日期：1997-12-11 00:00:00
abstract：:In the fasted state, increases in circulating glucagon promote hepatic glucose production through induction of the gluconeogenic program. Triggering of the cyclic AMP pathway increases gluconeogenic gene expression via the de-phosphorylation of the CREB co-activator CRTC2 (ref. 1). Glucagon promotes CRTC2 dephosphoryl...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature10988
更新日期：2012-04-08 00:00:00
abstract：:The Tasmanian devil, a large carnivorous Australian marsupial, is under threat from a widespread fatal disease in which a malignant oral-facial tumour obstructs the animal's ability to feed. Here we show that the chromosomes in these tumours have undergone a complex rearrangement that is identical for every animal stu...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/439549a
更新日期：2006-02-02 00:00:00
abstract：:In mammals, one of the most pronounced consequences of viral infection is the induction of type I interferons, cytokines with potent antiviral activity. Schlafen (Slfn) genes are a subset of interferon-stimulated early response genes (ISGs) that are also induced directly by pathogens via the interferon regulatory fact...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature11433
更新日期：2012-11-01 00:00:00
abstract：:Conifers have dominated forests for more than 200 million years and are of huge ecological and economic importance. Here we present the draft assembly of the 20-gigabase genome of Norway spruce (Picea abies), the first available for any gymnosperm. The number of well-supported genes (28,354) is similar to the >100 tim...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature12211
更新日期：2013-05-30 00:00:00
abstract：:To achieve stereoscopic vision, the brain must search for corresponding image features on the two retinas. As long as the eyes stay still, corresponding features are confined to narrow bands called epipolar lines. But when the eyes change position, the epipolar lines migrate on the retinas. To find the matching featur...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/35071081
更新日期：2001-04-12 00:00:00
abstract：:Aquaporin (AQP) water-channel proteins are freely permeated by water but not by ions or charged solutes. Although mammalian aquaporins were believed to be located in plasma membranes, rat AQP6 is restricted to intracellular vesicles in renal epithelia. Here we show that AQP6 is functionally distinct from other known a...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/46045
更新日期：1999-11-11 00:00:00
abstract：:The identical structure of two racially distinct alpha 1-globin alleles and the high degree of homology between the alpha 1- and alpha 2-globin loci indicate that mechanisms exist for suppression of allelic polymorphisms and for exchange of genetic information within the alpha-globin gene complex. ...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/290026a0
更新日期：1981-03-05 00:00:00
abstract：:Diseases of the vascular system result from a complex mixture of genetic and environmental factors. Data sets, technologies and strategies emanating from the human genome programme have been applied to the analysis of both rare single-gene and common multigenic vascular disorders. Genomic approaches including inter- a...
journal_title：Nature
pub_type： 杂志文章,评审
doi：10.1038/35025236
更新日期：2000-09-14 00:00:00
abstract：:Cancer control by adaptive immunity involves a number of defined death and clearance mechanisms. However, efficient inhibition of exponential cancer growth by T cells and interferon-γ (IFN-γ) requires additional undefined mechanisms that arrest cancer cell proliferation. Here we show that the combined action of the T-...
journal_title：Nature
pub_type： 杂志文章
doi：10.1038/nature11824
更新日期：2013-02-21 00:00:00
