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981.
Two major functions of the Golgi apparatus (GA) are formation of complex glycans and sorting of proteins destined for various
subcellular compartments or secretion. To fulfill these tasks proper localization of the accessory proteins within the different
sub-compartments of the GA is crucial. Here we investigate structural determinants mediating transition of the two glycosyltransferases
β-1,4- galactosyltransferase 1 (gal-T1) and the α-1,3-fucosyltransferase 6 (fuc-T6) from the trans-Golgi cisterna to the trans-Golgi network (TGN). Upon treatment with the ionophore monensin both glycosyltransferases are found in TGN-derived swollen
vesicles, as determined by confocal fluorescence microscopy and density gradient fractionation. Both enzymes carry a signal
consisting of the amino acids E5P6 in gal-T1 and D2P3 in fuc-T6 necessary for the transition of these glycosyltransferases from the trans-Golgi cisterna to the TGN, but not for their steady state localization in the trans-Golgi cisterna.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 30 July 2008; received after revision 17 September 2008; accepted 29 September 2008 相似文献
982.
Olfactory receptors typically exhibit poor plasma membrane localization and functionality when heterologously expressed in
most cell types. It has therefore proven difficult to effectively study olfactory receptor pharmacology and signaling mechanisms
using traditional cell culture systems. Over the past few years, a variety of distinct proteins have been reported to interact
with olfactory receptors and facilitate olfactory receptor trafficking to the plasma membrane in heterologous cells. Advances
in this area have shed significant light on the fundamental factors governing the cell-specific control of olfactory receptor
trafficking. 相似文献
983.
A. F. Vanin L. M. Bevers A. Slama-Schwok E. E. van Faassen 《Cellular and molecular life sciences : CMLS》2008,65(24):4066-4069
Announcement
Announcement 相似文献984.
Taylor DM Maxwell MM Luthi-Carter R Kazantsev AG 《Cellular and molecular life sciences : CMLS》2008,65(24):4000-4018
Sirtuins comprise a unique class of nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases that target multiple protein substrates to execute diverse biological functions. These enzymes are
key regulators of clinically important cellular and organismal processes, including metabolism, cell division and aging. The
desire to understand the important determinants of human health and lifespan has resulted in a firestorm of work on the seven
mammalian sirtuins in less than a decade. The implication of sirtuins in medically important areas such as diabetes, cancer,
cardiovascular dysfunction and neurodegenerative disease has further catapulted them to a prominent status as potential targets
for nutritional and therapeutic development. Here, we present a review of published results on sirtuin biology and its relevance
to human disease.
Received 25 June 2008; received after revision 20 August 2008; accepted 29 August 2008 相似文献
985.
It is generally thought that microtubule-associated motors insure long-range movements of the secretory vesicles from the center of the cell to its periphery, while myosins insure short-range movements at the cell periphery. However, several of the myosins that have been reported during the last decade to be involved in the exocytic pathway are not processive, meaning that they do not have the ability to move cargos along actin polymers. We will review here the possible mechanisms by which these myosins could contribute to the traffic of secretory proteins from the Golgi complex to the plasma membrane. 相似文献
986.
Zinc binding to peptide analogs of the structural zinc site in alcohol dehydrogenase: Implications for an entatic state 总被引:1,自引:0,他引:1
Bergman T Zhang K Palmberg C Jörnvall H Auld DS 《Cellular and molecular life sciences : CMLS》2008,65(24):4019-4027
Zinc binding to the peptide replica and analogs to residues 93–115 of horse liver alcohol dehydrogenase (ADH) was examined
by competition of the peptides and the chromophoric chelator 4-(2- pyridylazo)resorcinol for zinc and X-ray absorption fine
structure analysis of the zinc ligands. In the enzyme, zinc is coordinated by four Cys residues. In the peptide replica, zinc
is bound to three Cys and one His residue. A four-Cys zinc coordination is observed only when His is removed, leading to increased
zinc stability. ADH crystal structures reveal that the ε-amino group of the conserved residue Lys323 is within H-bond distance
of the backbone amide oxygens of residues 103, 105 and 108, likely stabilizing the zinc coordination in the enzyme. The peptide
data thus indicate structural strain and increased energy in the zinc-binding site in the protein, characteristic of an entatic
state, implying a functional nature for this zinc site.
Received 3 July 2008; received after revision 11 August 2008; accepted 1 September 2008 相似文献
987.
Cardiolipin, the heart of mitochondrial metabolism 总被引:5,自引:0,他引:5
Cardiolipin is a unique phospholipid, which is almost exclusively localized in the mitochondrial inner membrane where it is
synthesized from phosphatidylglycerol and cytidinediphosphate-diacylglycerol. After primary synthesis, the mature acyl chain
composition of cardiolipin is achieved by at least two remodeling mechanisms. In the mitochondrial membrane cardiolipin plays
an important role in energy metabolism, mainly by providing stability for the individual enzymes and enzyme complexes involved
in energy production. Moreover, cardiolipin is involved in different stages of the mitochondrial apoptotic process and in
mitochondrial membrane dynamics. Cardiolipin alterations have been described in various pathological conditions. Patients
suffering from Barth syndrome have an altered cardiolipin homeostasis caused by a primary deficiency in cardiolipin remodeling.
Alterations in cardiolipin content or composition have also been reported in more frequent diseases such as diabetes and heart
failure. In this review we provide an overview of cardiolipin metabolism, function and its role in different pathological
states.
Received 16 January 2008; received after revision 26 February 2008; accepted 26 March 2008 相似文献
988.
Galat A 《Cellular and molecular life sciences : CMLS》2008,65(21):3481-3493
Extracellular domains of some cellular receptors expressed in the organisms at different levels of development belong to three-fingered
protein (TFP) fold. The Homo sapiens genome encodes at least 45 genes containing from one to three TFP domains (TFPDs), namely diverse paralogues of the Ly6 gene,
CD59 and the receptors of activins, bone morphogenetic proteins, Mullerian inhibiting substance and transforming growth factor-β.
C4.4a and urokinase/plasminogen activatory receptor contain two and three TFPD repeats, respectively. These diverse proteins
have a low overall sequence similarity with each other and their hydrophobicity levels vary to a considerable degree. It is
suggested that sequence differentiation within the TFPD led to distinct groups of proteins whose attributes were optimized
to fit both the physicochemical properties specific to their functional microenvironment and selective targeting of their
highly diversified extracellular cofactors.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 7 August 2008; accepted 29 August 2008 相似文献
989.
计算机网络系统正常工作模式和故障模式分析 总被引:1,自引:0,他引:1
提出了考虑网络节点可靠性时,计算机网络系统正常工作模式和故障模式分析方法.通过比较不考虑节点可靠性和考虑节点可靠性条件下,计算机网络系统正常工作模式和故障模式变化,说明在计算机网络系统可靠性与安全性分析时,考虑节点可靠性的必要性. 相似文献
990.
脱硫催化剂的酸法制备及性能研究 总被引:4,自引:0,他引:4
对用酸法进行催化剂制备,酸法制备的最佳镁铝比,分散介质的优化,引入对脱催化剂的氧化性能和还原性能的影响。以及实验室的还原温度等诸方面进行了研究。 相似文献