The Experts below are selected from a list of 10725 Experts worldwide ranked by ideXlab platform
Julia Majewska - One of the best experts on this subject based on the ideXlab platform.
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overlapping binding sites of the frataxin homologue assembly factor and the heat shock protein 70 transfer factor on the isu iron sulfur cluster scaffold protein
Journal of Biological Chemistry, 2014Co-Authors: Mateusz Manicki, Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A CraigAbstract:In mitochondria FeS clusters, prosthetic groups critical for the activity of many proteins, are first assembled on Isu, a 14-kDa scaffold protein, and then transferred to recipient apoproteins. The assembly process involves interaction of Isu with both Nfs1, the cysteine desulfurase serving as a sulfur donor, and the yeast frataxin homolog (Yfh1) serving as a regulator of desulfurase activity and/or iron donor. Here, based on the results of biochemical experiments with purified wild-type and variant proteins, we report that interaction of Yfh1 with both Nfs1 and Isu are required for formation of a stable tripartite assembly complex. Disruption of either Yfh1-Isu or Nfs1-Isu interactions destabilizes the complex. Cluster transfer to recipient apoprotein is known to require the interaction of Isu with the J-protein/Hsp70 molecular chaperone pair, Jac1 and Ssq1. Here we show that the Yfh1 interaction with Isu involves the PVK sequence motif, which is also the site key for the interaction of Isu with Hsp70 Ssq1. Coupled with our previous observation that Nfs1 and Jac1 binding to Isu is mutually exclusive due to partially overlapping binding sites, we propose that such mutual exclusivity of cluster assembly factor (Nfs1/Yfh1) and cluster transfer factor (Jac1/Ssq1) binding to Isu has functional consequences for the transition from the assembly process to the transfer process, and thus regulation of the biogenesis of FeS cluster proteins.
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overlapping binding sites of the frataxin homologue assembly factor and the heat shock protein 70 transfer factor on the isu iron sulfur cluster scaffold protein
Journal of Biological Chemistry, 2014Co-Authors: Mateusz Manicki, Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A Craig, Rafal DutkiewiczAbstract:Abstract In mitochondria Fe-S clusters, prosthetic groups critical for the activity of many proteins, are first assembled on Isu, a 14 kDa scaffold protein, and then transferred to recipient apo-proteins. The assembly process involves interaction of Isu with both Nfs1, the cysteine desulfurase serving as a sulfur donor, and the yeast frataxin homolog (Yfh1) serving as a regulator of desulfurase activity and/or iron donor. Here, based on the results of biochemical experiments with purified wild-type and variant proteins, we report that interaction of Yfh1 with both Nfs1 and Isu are required for formation of a stable tripartite assembly complex. Disruption of either the Yfh1-Isu or the Nfs1-Isu interaction destabilizes the complex. Cluster transfer to recipient apo-protein is known to require the interaction of Isu with the J-protein/Hsp70 molecular chaperone pair, Jac1 and Ssq1. Here we show that Yfh1 interaction with Isu involves the PVK sequence motif, which is also the site key for the interaction of Isu with Hsp70 Ssq1. Coupled with our previous observation that Nfs1 and Jac1 binding to Isu is mutually exclusive due to partially overlapping binding sites, we propose that such mutual exclusivity of cluster assembly factor (Nfs1/Yfh1) and cluster transfer factor (Jac1/Ssq1) binding to Isu has functional consequences for the transition from the assembly process to the transfer process, and thus regulation of the biogenesis of Fe-S cluster proteins.
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binding of the chaperone jac1 protein and cysteine desulfurase nfs1 to the iron sulfur cluster scaffold isu protein is mutually exclusive
Journal of Biological Chemistry, 2013Co-Authors: Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A Craig, Wojciech Delewski, Jiyoon Song, Rafal DutkiewiczAbstract:Biogenesis of mitochondrial iron-sulfur (Fe/S) cluster proteins requires the interaction of multiple proteins with the highly conserved 14-kDa scaffold protein Isu, on which clusters are built prior to their transfer to recipient proteins. For example, the assembly process requires the cysteine desulfurase Nfs1, which serves as the sulfur donor for cluster assembly. The transfer process requires Jac1, a J-protein Hsp70 cochaperone. We recently identified three residues on the surface of Jac1 that form a hydrophobic patch critical for interaction with Isu. The results of molecular modeling of the Isu1-Jac1 interaction, which was guided by these experimental data and structural/biophysical information available for bacterial homologs, predicted the importance of three hydrophobic residues forming a patch on the surface of Isu1 for interaction with Jac1. Using Isu variants having alterations in residues that form the hydrophobic patch on the surface of Isu, this prediction was experimentally validated by in vitro binding assays. In addition, Nfs1 was found to require the same hydrophobic residues of Isu for binding, as does Jac1, suggesting that Jac1 and Nfs1 binding is mutually exclusive. In support of this conclusion, Jac1 and Nfs1 compete for binding to Isu. Evolutionary analysis revealed that residues involved in these interactions are conserved and that they are critical residues for the biogenesis of Fe/S cluster protein in vivo. We propose that competition between Jac1 and Nfs1 for Isu binding plays an important role in transitioning the Fe/S cluster biogenesis machinery from the cluster assembly step to the Hsp70-mediated transfer of the Fe/S cluster to recipient proteins.
Elizabeth A Craig - One of the best experts on this subject based on the ideXlab platform.
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overlapping binding sites of the frataxin homologue assembly factor and the heat shock protein 70 transfer factor on the isu iron sulfur cluster scaffold protein
Journal of Biological Chemistry, 2014Co-Authors: Mateusz Manicki, Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A CraigAbstract:In mitochondria FeS clusters, prosthetic groups critical for the activity of many proteins, are first assembled on Isu, a 14-kDa scaffold protein, and then transferred to recipient apoproteins. The assembly process involves interaction of Isu with both Nfs1, the cysteine desulfurase serving as a sulfur donor, and the yeast frataxin homolog (Yfh1) serving as a regulator of desulfurase activity and/or iron donor. Here, based on the results of biochemical experiments with purified wild-type and variant proteins, we report that interaction of Yfh1 with both Nfs1 and Isu are required for formation of a stable tripartite assembly complex. Disruption of either Yfh1-Isu or Nfs1-Isu interactions destabilizes the complex. Cluster transfer to recipient apoprotein is known to require the interaction of Isu with the J-protein/Hsp70 molecular chaperone pair, Jac1 and Ssq1. Here we show that the Yfh1 interaction with Isu involves the PVK sequence motif, which is also the site key for the interaction of Isu with Hsp70 Ssq1. Coupled with our previous observation that Nfs1 and Jac1 binding to Isu is mutually exclusive due to partially overlapping binding sites, we propose that such mutual exclusivity of cluster assembly factor (Nfs1/Yfh1) and cluster transfer factor (Jac1/Ssq1) binding to Isu has functional consequences for the transition from the assembly process to the transfer process, and thus regulation of the biogenesis of FeS cluster proteins.
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overlapping binding sites of the frataxin homologue assembly factor and the heat shock protein 70 transfer factor on the isu iron sulfur cluster scaffold protein
Journal of Biological Chemistry, 2014Co-Authors: Mateusz Manicki, Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A Craig, Rafal DutkiewiczAbstract:Abstract In mitochondria Fe-S clusters, prosthetic groups critical for the activity of many proteins, are first assembled on Isu, a 14 kDa scaffold protein, and then transferred to recipient apo-proteins. The assembly process involves interaction of Isu with both Nfs1, the cysteine desulfurase serving as a sulfur donor, and the yeast frataxin homolog (Yfh1) serving as a regulator of desulfurase activity and/or iron donor. Here, based on the results of biochemical experiments with purified wild-type and variant proteins, we report that interaction of Yfh1 with both Nfs1 and Isu are required for formation of a stable tripartite assembly complex. Disruption of either the Yfh1-Isu or the Nfs1-Isu interaction destabilizes the complex. Cluster transfer to recipient apo-protein is known to require the interaction of Isu with the J-protein/Hsp70 molecular chaperone pair, Jac1 and Ssq1. Here we show that Yfh1 interaction with Isu involves the PVK sequence motif, which is also the site key for the interaction of Isu with Hsp70 Ssq1. Coupled with our previous observation that Nfs1 and Jac1 binding to Isu is mutually exclusive due to partially overlapping binding sites, we propose that such mutual exclusivity of cluster assembly factor (Nfs1/Yfh1) and cluster transfer factor (Jac1/Ssq1) binding to Isu has functional consequences for the transition from the assembly process to the transfer process, and thus regulation of the biogenesis of Fe-S cluster proteins.
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binding of the chaperone jac1 protein and cysteine desulfurase nfs1 to the iron sulfur cluster scaffold isu protein is mutually exclusive
Journal of Biological Chemistry, 2013Co-Authors: Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A Craig, Wojciech Delewski, Jiyoon Song, Rafal DutkiewiczAbstract:Biogenesis of mitochondrial iron-sulfur (Fe/S) cluster proteins requires the interaction of multiple proteins with the highly conserved 14-kDa scaffold protein Isu, on which clusters are built prior to their transfer to recipient proteins. For example, the assembly process requires the cysteine desulfurase Nfs1, which serves as the sulfur donor for cluster assembly. The transfer process requires Jac1, a J-protein Hsp70 cochaperone. We recently identified three residues on the surface of Jac1 that form a hydrophobic patch critical for interaction with Isu. The results of molecular modeling of the Isu1-Jac1 interaction, which was guided by these experimental data and structural/biophysical information available for bacterial homologs, predicted the importance of three hydrophobic residues forming a patch on the surface of Isu1 for interaction with Jac1. Using Isu variants having alterations in residues that form the hydrophobic patch on the surface of Isu, this prediction was experimentally validated by in vitro binding assays. In addition, Nfs1 was found to require the same hydrophobic residues of Isu for binding, as does Jac1, suggesting that Jac1 and Nfs1 binding is mutually exclusive. In support of this conclusion, Jac1 and Nfs1 compete for binding to Isu. Evolutionary analysis revealed that residues involved in these interactions are conserved and that they are critical residues for the biogenesis of Fe/S cluster protein in vivo. We propose that competition between Jac1 and Nfs1 for Isu binding plays an important role in transitioning the Fe/S cluster biogenesis machinery from the cluster assembly step to the Hsp70-mediated transfer of the Fe/S cluster to recipient proteins.
Hongwei Ren - One of the best experts on this subject based on the ideXlab platform.
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isotope geochemistry of mercury and its relation to earthquake in the wenchuan earthquake fault scientific drilling project hole 1 wfsd 1
Tectonophysics, 2014Co-Authors: Lei Zhang, Zhen Fang, Yaowei Liu, Duoxing Yang, Lishuang Guo, Tao Chen, Hongwei RenAbstract:Abstract Based on the Wenchuan Earthquake Fault Scientific Drilling Project (WFSD), we first investigated the distribution of the total mercury (THg) from 600 m to 1035 m of WFSD Hole-1 core (WFSD-1). The concentrations of THg in the fault gouge are significantly higher than in the sandstone, shale, siltstone, and cataclasite in WFSD-1. The THg concentrations in the main seismic fault zone range from 9.9 to 73.5 ng/g while those under the main fault range from 20.5 to 36 ng/g. To determine the source of Hg, typical rocks from different depths were chosen for Hg isotope analysis. The results show that δ202Hg in the main seismic fault zone range from − 0.11‰ to − 2.68‰, and, below the seismic fault zone, δ202Hg are from − 0.64‰ to − 1.33‰. The seismic fault rocks are more enriched in THg and have a larger variation of δ202Hg compared to the other rocks. Mercury has different isotopic compositions and fractionation mechanisms in the fault zone, which are mainly affected by the earthquake and the fluid. The mercury isotope compositions reflect the fluid activities at the main fault zone. We demonstrate that mercury stable isotope ratios could serve as an effective tool for tracing mercury sources and monitoring and predicting earthquakes.
Jaroslaw Marszalek - One of the best experts on this subject based on the ideXlab platform.
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overlapping binding sites of the frataxin homologue assembly factor and the heat shock protein 70 transfer factor on the isu iron sulfur cluster scaffold protein
Journal of Biological Chemistry, 2014Co-Authors: Mateusz Manicki, Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A CraigAbstract:In mitochondria FeS clusters, prosthetic groups critical for the activity of many proteins, are first assembled on Isu, a 14-kDa scaffold protein, and then transferred to recipient apoproteins. The assembly process involves interaction of Isu with both Nfs1, the cysteine desulfurase serving as a sulfur donor, and the yeast frataxin homolog (Yfh1) serving as a regulator of desulfurase activity and/or iron donor. Here, based on the results of biochemical experiments with purified wild-type and variant proteins, we report that interaction of Yfh1 with both Nfs1 and Isu are required for formation of a stable tripartite assembly complex. Disruption of either Yfh1-Isu or Nfs1-Isu interactions destabilizes the complex. Cluster transfer to recipient apoprotein is known to require the interaction of Isu with the J-protein/Hsp70 molecular chaperone pair, Jac1 and Ssq1. Here we show that the Yfh1 interaction with Isu involves the PVK sequence motif, which is also the site key for the interaction of Isu with Hsp70 Ssq1. Coupled with our previous observation that Nfs1 and Jac1 binding to Isu is mutually exclusive due to partially overlapping binding sites, we propose that such mutual exclusivity of cluster assembly factor (Nfs1/Yfh1) and cluster transfer factor (Jac1/Ssq1) binding to Isu has functional consequences for the transition from the assembly process to the transfer process, and thus regulation of the biogenesis of FeS cluster proteins.
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overlapping binding sites of the frataxin homologue assembly factor and the heat shock protein 70 transfer factor on the isu iron sulfur cluster scaffold protein
Journal of Biological Chemistry, 2014Co-Authors: Mateusz Manicki, Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A Craig, Rafal DutkiewiczAbstract:Abstract In mitochondria Fe-S clusters, prosthetic groups critical for the activity of many proteins, are first assembled on Isu, a 14 kDa scaffold protein, and then transferred to recipient apo-proteins. The assembly process involves interaction of Isu with both Nfs1, the cysteine desulfurase serving as a sulfur donor, and the yeast frataxin homolog (Yfh1) serving as a regulator of desulfurase activity and/or iron donor. Here, based on the results of biochemical experiments with purified wild-type and variant proteins, we report that interaction of Yfh1 with both Nfs1 and Isu are required for formation of a stable tripartite assembly complex. Disruption of either the Yfh1-Isu or the Nfs1-Isu interaction destabilizes the complex. Cluster transfer to recipient apo-protein is known to require the interaction of Isu with the J-protein/Hsp70 molecular chaperone pair, Jac1 and Ssq1. Here we show that Yfh1 interaction with Isu involves the PVK sequence motif, which is also the site key for the interaction of Isu with Hsp70 Ssq1. Coupled with our previous observation that Nfs1 and Jac1 binding to Isu is mutually exclusive due to partially overlapping binding sites, we propose that such mutual exclusivity of cluster assembly factor (Nfs1/Yfh1) and cluster transfer factor (Jac1/Ssq1) binding to Isu has functional consequences for the transition from the assembly process to the transfer process, and thus regulation of the biogenesis of Fe-S cluster proteins.
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binding of the chaperone jac1 protein and cysteine desulfurase nfs1 to the iron sulfur cluster scaffold isu protein is mutually exclusive
Journal of Biological Chemistry, 2013Co-Authors: Julia Majewska, Szymon J Ciesielski, Brenda Schilke, Anna Blenska, Jacek Kominek, Jaroslaw Marszalek, Elizabeth A Craig, Wojciech Delewski, Jiyoon Song, Rafal DutkiewiczAbstract:Biogenesis of mitochondrial iron-sulfur (Fe/S) cluster proteins requires the interaction of multiple proteins with the highly conserved 14-kDa scaffold protein Isu, on which clusters are built prior to their transfer to recipient proteins. For example, the assembly process requires the cysteine desulfurase Nfs1, which serves as the sulfur donor for cluster assembly. The transfer process requires Jac1, a J-protein Hsp70 cochaperone. We recently identified three residues on the surface of Jac1 that form a hydrophobic patch critical for interaction with Isu. The results of molecular modeling of the Isu1-Jac1 interaction, which was guided by these experimental data and structural/biophysical information available for bacterial homologs, predicted the importance of three hydrophobic residues forming a patch on the surface of Isu1 for interaction with Jac1. Using Isu variants having alterations in residues that form the hydrophobic patch on the surface of Isu, this prediction was experimentally validated by in vitro binding assays. In addition, Nfs1 was found to require the same hydrophobic residues of Isu for binding, as does Jac1, suggesting that Jac1 and Nfs1 binding is mutually exclusive. In support of this conclusion, Jac1 and Nfs1 compete for binding to Isu. Evolutionary analysis revealed that residues involved in these interactions are conserved and that they are critical residues for the biogenesis of Fe/S cluster protein in vivo. We propose that competition between Jac1 and Nfs1 for Isu binding plays an important role in transitioning the Fe/S cluster biogenesis machinery from the cluster assembly step to the Hsp70-mediated transfer of the Fe/S cluster to recipient proteins.
Dongliang Liu - One of the best experts on this subject based on the ideXlab platform.
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structural and physical property characterization in the wenchuan earthquake fault scientific drilling project hole 1 wfsd 1
Tectonophysics, 2014Co-Authors: Yixiong Niu, Guangsheng Kong, Yao Huang, Huan Wang, Zhiming Sun, Junling Pei, Zheng Gong, Marieluce Chevalier, Dongliang LiuAbstract:Abstract The Wenchuan earthquake Fault Scientific Drilling project (WFSD) started right after the 2008 Mw 7.9 Wenchuan earthquake to investigate its faulting mechanism. Hole 1 (WFSD-1) reached the Yingxiu–Beichuan fault (YBF), and core samples were recovered from 32 to 1201.15 m-depth. Core investigation and a suite of geophysical downhole logs (including P-wave velocity, natural gamma ray, self-potential, resistivity, density, porosity, temperature, magnetic susceptibility and ultrasound borehole images) were acquired in WFSD-1. Integrated studies of cores and logs facilitate qualitative and quantitative comparison of the structures and physical properties of rocks. Logging data revealed that the geothermal gradient of the volcanic Pengguan complex (above 585.75 m) is 1.85 °C/100 m, while that of the sedimentary Xujiahe Formation (below 585.75 m) is 2.15 °C/100 m. In general, natural gamma ray, resistivity, density, porosity, P-wave velocity and magnetic susceptibility primarily depend on the rock lithology. All major fault zones are characterized by high magnetic susceptibility, low density and high porosity, with mostly low resistivity, high natural gamma ray and sound wave velocity. The high magnetic susceptibility values most likely result from the transformation of magnetic minerals by frictional heating due to the earthquake. The YBF exposed in WFSD-1 can be subdivided into five different parts based on different logging responses, each of them corresponding to certain fault-rocks. The high gamma radiation, porosity and P-wave velocity, as well as low resistivity and temperature anomalies indicate that the Wenchuan earthquake fault zone is located at 585.75–594.5 m-depth, with an average inclination and dip angle of N305° and 71°, respectively. The fact that the fracture directions in the hanging wall and footwall are different suggests that their stress field direction is completely different, implying that the upper Pengguan complex may not be local.
