The Experts below are selected from a list of 42 Experts worldwide ranked by ideXlab platform
Jacques Chomilier - One of the best experts on this subject based on the ideXlab platform.
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Sequence analyses reveal that a TPR–DP module, surrounded by recombinable flanking introns, could be at the origin of eukaryotic Hop and Hip TPR–DP domains and prokaryotic GerD Proteins
Cell Stress and Chaperones, 2009Co-Authors: Jorge Hernández Torres, Nikolaos Papandreou, Jacques ChomilierAbstract:The co-chaperone Hop [heat shock Protein (HSP) organising Protein] is known to bind both Hsp70 and Hsp90. Hop comprises three repeats of a tetratricopeptide repeat (TPR) domain, each consisting of three TPR motifs. The first and last TPR domains are followed by a domain containing several dipeptide (DP) repeats called the DP domain. These analyses suggest that the Hop genes result from successive recombination events of an ancestral TPR–DP module. From a hydrophobic cluster analysis of homologous Hop Protein sequences derived from gene families, we can postulate that shifts in the open reading frames are at the origin of the present sequences. Moreover, these shifts can be related to the presence or absence of biological function. We propose to extend the family of Hop co-chaperons into the kingdom of bacteria, as several structurally related genes have been identified by hydrophobic cluster analysis. We also provide evidence of common structural characteristics between Hop and hip genes, suggesting a shared precursor of ancestral TPR–DP domains.
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Sequence analyses reveal that a TPR-DP module, surrounded by recombinable flanking introns, could be at the origin of eukaryotic Hop and Hip TPR-DP domains and prokaryotic GerD Proteins.
Cell Stress & Chaperones, 2008Co-Authors: Jorge Hernández Torres, Nikolaos Papandreou, Jacques ChomilierAbstract:The co-chaperone Hop [heat shock Protein (HSP) organising Protein] is known to bind both Hsp70 and Hsp90. Hop comprises three repeats of a tetratricopeptide repeat (TPR) domain, each consisting of three TPR motifs. The first and last TPR domains are followed by a domain containing several dipeptide (DP) repeats called the DP domain. These analyses suggest that the Hop genes result from successive recombination events of an ancestral TPR–DP module. From a hydrophobic cluster analysis of homologous Hop Protein sequences derived from gene families, we can postulate that shifts in the open reading frames are at the origin of the present sequences. Moreover, these shifts can be related to the presence or absence of biological function. We propose to extend the family of Hop co-chaperons into the kingdom of bacteria, as several structurally related genes have been identified by hydrophobic cluster analysis. We also provide evidence of common structural characteristics between Hop and hip genes, suggesting a shared precursor of ancestral TPR–DP domains.
Jorge Hernández Torres - One of the best experts on this subject based on the ideXlab platform.
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Sequence analyses reveal that a TPR–DP module, surrounded by recombinable flanking introns, could be at the origin of eukaryotic Hop and Hip TPR–DP domains and prokaryotic GerD Proteins
Cell Stress and Chaperones, 2009Co-Authors: Jorge Hernández Torres, Nikolaos Papandreou, Jacques ChomilierAbstract:The co-chaperone Hop [heat shock Protein (HSP) organising Protein] is known to bind both Hsp70 and Hsp90. Hop comprises three repeats of a tetratricopeptide repeat (TPR) domain, each consisting of three TPR motifs. The first and last TPR domains are followed by a domain containing several dipeptide (DP) repeats called the DP domain. These analyses suggest that the Hop genes result from successive recombination events of an ancestral TPR–DP module. From a hydrophobic cluster analysis of homologous Hop Protein sequences derived from gene families, we can postulate that shifts in the open reading frames are at the origin of the present sequences. Moreover, these shifts can be related to the presence or absence of biological function. We propose to extend the family of Hop co-chaperons into the kingdom of bacteria, as several structurally related genes have been identified by hydrophobic cluster analysis. We also provide evidence of common structural characteristics between Hop and hip genes, suggesting a shared precursor of ancestral TPR–DP domains.
Nikolaos Papandreou - One of the best experts on this subject based on the ideXlab platform.
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Sequence analyses reveal that a TPR–DP module, surrounded by recombinable flanking introns, could be at the origin of eukaryotic Hop and Hip TPR–DP domains and prokaryotic GerD Proteins
Cell Stress and Chaperones, 2009Co-Authors: Jorge Hernández Torres, Nikolaos Papandreou, Jacques ChomilierAbstract:The co-chaperone Hop [heat shock Protein (HSP) organising Protein] is known to bind both Hsp70 and Hsp90. Hop comprises three repeats of a tetratricopeptide repeat (TPR) domain, each consisting of three TPR motifs. The first and last TPR domains are followed by a domain containing several dipeptide (DP) repeats called the DP domain. These analyses suggest that the Hop genes result from successive recombination events of an ancestral TPR–DP module. From a hydrophobic cluster analysis of homologous Hop Protein sequences derived from gene families, we can postulate that shifts in the open reading frames are at the origin of the present sequences. Moreover, these shifts can be related to the presence or absence of biological function. We propose to extend the family of Hop co-chaperons into the kingdom of bacteria, as several structurally related genes have been identified by hydrophobic cluster analysis. We also provide evidence of common structural characteristics between Hop and hip genes, suggesting a shared precursor of ancestral TPR–DP domains.
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Sequence analyses reveal that a TPR-DP module, surrounded by recombinable flanking introns, could be at the origin of eukaryotic Hop and Hip TPR-DP domains and prokaryotic GerD Proteins.
Cell Stress & Chaperones, 2008Co-Authors: Jorge Hernández Torres, Nikolaos Papandreou, Jacques ChomilierAbstract:The co-chaperone Hop [heat shock Protein (HSP) organising Protein] is known to bind both Hsp70 and Hsp90. Hop comprises three repeats of a tetratricopeptide repeat (TPR) domain, each consisting of three TPR motifs. The first and last TPR domains are followed by a domain containing several dipeptide (DP) repeats called the DP domain. These analyses suggest that the Hop genes result from successive recombination events of an ancestral TPR–DP module. From a hydrophobic cluster analysis of homologous Hop Protein sequences derived from gene families, we can postulate that shifts in the open reading frames are at the origin of the present sequences. Moreover, these shifts can be related to the presence or absence of biological function. We propose to extend the family of Hop co-chaperons into the kingdom of bacteria, as several structurally related genes have been identified by hydrophobic cluster analysis. We also provide evidence of common structural characteristics between Hop and hip genes, suggesting a shared precursor of ancestral TPR–DP domains.
Klaus Richter - One of the best experts on this subject based on the ideXlab platform.
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the non canonical Hop Protein from caenorhabditis elegans exerts essential functions and forms binary complexes with either hsc70 or hsp90
Journal of Molecular Biology, 2009Co-Authors: Andreas Gaiser, Florian Brandt, Klaus RichterAbstract:Heat shock Protein (Hsp) 70/Hsp90-organizing Proteins (Hop/Sti1) are thought to function as adaptor Proteins to link the two chaperone machineries Hsp70 and Hsp90 during the processing of substrate Proteins in eukaryotes. Hop (Hsp70/Hsp90-organizing Protein) is composed of three tetratricopeptide repeat (TPR) domains, of which the first (TPR1) binds to Hsp70, the second (TPR2A) binds to Hsp90, and the third (TPR2B) is of unknown function. Contrary to most other eukaryotes, the homologue closest to the Caenorhabditis elegans Hop homologue R09E12.3 (CeHop) lacks the TPR1 domain and the short linker region connecting it to TPR2A, questioning the reported function as an Hsp90/Hsp70 adaptor in vitro and in vivo. We observed high constitutive expression levels of CeHop and detected significant phenotypes upon knockdown, linking the Protein to functions in gonad development. Interestingly, we observed physical interactions with both chaperones Hsp70 and Hsp90, albeit only the interaction with Hsp90 is strong and inhibition of the Hsp90 ATPase activity can be observed upon binding of CeHop. However, the formation of ternary complexes with both chaperone machineries is impaired, as Hsp70 and Hsp90 compete for CeHop interaction sites, in particular as Hsp90 binds to both TPR domains simultaneously and requires both TPR domains for ATPase regulation. These results imply that, at least in C. elegans, essential functions of Hop exist which apparently do not depend on the simultaneous binding of Hsp90 and Hsp70 to Hop.
Jorge Hernández Torres - One of the best experts on this subject based on the ideXlab platform.
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Sequence analyses reveal that a TPR-DP module, surrounded by recombinable flanking introns, could be at the origin of eukaryotic Hop and Hip TPR-DP domains and prokaryotic GerD Proteins.
Cell Stress & Chaperones, 2008Co-Authors: Jorge Hernández Torres, Nikolaos Papandreou, Jacques ChomilierAbstract:The co-chaperone Hop [heat shock Protein (HSP) organising Protein] is known to bind both Hsp70 and Hsp90. Hop comprises three repeats of a tetratricopeptide repeat (TPR) domain, each consisting of three TPR motifs. The first and last TPR domains are followed by a domain containing several dipeptide (DP) repeats called the DP domain. These analyses suggest that the Hop genes result from successive recombination events of an ancestral TPR–DP module. From a hydrophobic cluster analysis of homologous Hop Protein sequences derived from gene families, we can postulate that shifts in the open reading frames are at the origin of the present sequences. Moreover, these shifts can be related to the presence or absence of biological function. We propose to extend the family of Hop co-chaperons into the kingdom of bacteria, as several structurally related genes have been identified by hydrophobic cluster analysis. We also provide evidence of common structural characteristics between Hop and hip genes, suggesting a shared precursor of ancestral TPR–DP domains.