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Journal Articles
2011
51.
Leonardi E; Andreazza S; Vanin S; Busolin G; Nobile C; Tosatto S C E
A computational model of the LGI1 protein suggests a common binding site for ADAM proteins Journal Article
In: PLoS ONE, vol. 6, no. 3, 2011, (Cited by: 36; Open Access).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:79953202854,
title = {A computational model of the LGI1 protein suggests a common binding site for ADAM proteins},
author = {Emanuela Leonardi and Simonetta Andreazza and Stefano Vanin and Giorgia Busolin and Carlo Nobile and Silvio C. E. Tosatto},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-79953202854&origin=inward},
doi = {10.1371/journal.pone.0018142},
year = {2011},
date = {2011-01-01},
journal = {PLoS ONE},
volume = {6},
number = {3},
abstract = {Mutations of human leucine-rich glioma inactivated (LGI1) gene encoding the epitempin protein cause autosomal dominant temporal lateral epilepsy (ADTLE), a rare familial partial epileptic syndrome. The LGI1 gene seems to have a role on the transmission of neuronal messages but the exact molecular mechanism remains unclear. In contrast to other genes involved in epileptic disorders, epitempin shows no homology with known ion channel genes but contains two domains, composed of repeated structural units, known to mediate protein-protein interactions. A three dimensional in silico model of the two epitempin domains was built to predict the structure-function relationship and propose a functional model integrating previous experimental findings. Conserved and electrostatic charged regions of the model surface suggest a possible arrangement between the two domains and identifies a possible ADAM protein binding site in the β-propeller domain and another protein binding site in the leucine-rich repeat domain. The functional model indicates that epitempin could mediate the interaction between proteins localized to different synaptic sides in a static way, by forming a dimer, or in a dynamic way, by binding proteins at different times. The model was also used to predict effects of known disease-causing missense mutations. Most of the variants are predicted to alter protein folding while several other map to functional surface regions. In agreement with experimental evidence, this suggests that non-secreted LGI1 mutants could be retained within the cell by quality control mechanisms or by altering interactions required for the secretion process. © 2011 Leonardi et al.},
note = {Cited by: 36; Open Access},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Mutations of human leucine-rich glioma inactivated (LGI1) gene encoding the epitempin protein cause autosomal dominant temporal lateral epilepsy (ADTLE), a rare familial partial epileptic syndrome. The LGI1 gene seems to have a role on the transmission of neuronal messages but the exact molecular mechanism remains unclear. In contrast to other genes involved in epileptic disorders, epitempin shows no homology with known ion channel genes but contains two domains, composed of repeated structural units, known to mediate protein-protein interactions. A three dimensional in silico model of the two epitempin domains was built to predict the structure-function relationship and propose a functional model integrating previous experimental findings. Conserved and electrostatic charged regions of the model surface suggest a possible arrangement between the two domains and identifies a possible ADAM protein binding site in the β-propeller domain and another protein binding site in the leucine-rich repeat domain. The functional model indicates that epitempin could mediate the interaction between proteins localized to different synaptic sides in a static way, by forming a dimer, or in a dynamic way, by binding proteins at different times. The model was also used to predict effects of known disease-causing missense mutations. Most of the variants are predicted to alter protein folding while several other map to functional surface regions. In agreement with experimental evidence, this suggests that non-secreted LGI1 mutants could be retained within the cell by quality control mechanisms or by altering interactions required for the secretion process. © 2011 Leonardi et al.
52.
Leonardi E; Martella M; Tosatto S C E; Murgia A
Identification and In Silico Analysis of Novel von Hippel-Lindau (VHL) Gene Variants from a Large Population Journal Article
In: Annals of Human Genetics, vol. 75, no. 4, pp. 483-496, 2011, (Cited by: 21).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:79958845071,
title = {Identification and In Silico Analysis of Novel von Hippel-Lindau (VHL) Gene Variants from a Large Population},
author = {Emanuela Leonardi and Maddalena Martella and Silvio C. E. Tosatto and Alessandra Murgia},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-79958845071&origin=inward},
doi = {10.1111/j.1469-1809.2011.00647.x},
year = {2011},
date = {2011-01-01},
journal = {Annals of Human Genetics},
volume = {75},
number = {4},
pages = {483-496},
abstract = {Mutational inactivation of the VHL gene is the cause of von Hippel-Lindau (VHL) disease, an autosomal dominant hereditary cancer syndrome predisposing to haemangioblastomas, pheochromocytomas and clear-cell renal carcinomas. The gene product (pVHL) functions as an adapter in cellular processes including cell growth and apoptosis. VHL mutation analysis was carried out in 426 unrelated subjects with phenotypes ranging from VHL syndrome, to isolated VHL-related tumours that could represent the first manifestation of the disease. A total of 111 individuals were found to carry alterations, with large deletions representing 40% of the variants. Eighteen of the 95 detected variants were novel, seemingly disease-causing mutations; their pathogenic role has been evaluated in silico for effects on protein folding and interactions. Putative regions of interaction between pVHL and proteins involved in common pathways have been identified, assessing possible implications for the presence of mutations in these regions. All new variants predicted to truncate or cause complete pVHL loss of structure were associated with phenotypes consistent with VHL type 1. Seven of the new amino acid substitutions are disease-causing mutations, one is a neutral variant, whereas the results for two remain ambiguous. Our combined molecular and in silico approach for the evaluation of putative disease-causing mutations contributes to the interpretation of the potential pathogenicity of these novel variants. © 2011 The Authors Annals of Human Genetics © 2011 Blackwell Publishing Ltd/University College London.},
note = {Cited by: 21},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Mutational inactivation of the VHL gene is the cause of von Hippel-Lindau (VHL) disease, an autosomal dominant hereditary cancer syndrome predisposing to haemangioblastomas, pheochromocytomas and clear-cell renal carcinomas. The gene product (pVHL) functions as an adapter in cellular processes including cell growth and apoptosis. VHL mutation analysis was carried out in 426 unrelated subjects with phenotypes ranging from VHL syndrome, to isolated VHL-related tumours that could represent the first manifestation of the disease. A total of 111 individuals were found to carry alterations, with large deletions representing 40% of the variants. Eighteen of the 95 detected variants were novel, seemingly disease-causing mutations; their pathogenic role has been evaluated in silico for effects on protein folding and interactions. Putative regions of interaction between pVHL and proteins involved in common pathways have been identified, assessing possible implications for the presence of mutations in these regions. All new variants predicted to truncate or cause complete pVHL loss of structure were associated with phenotypes consistent with VHL type 1. Seven of the new amino acid substitutions are disease-causing mutations, one is a neutral variant, whereas the results for two remain ambiguous. Our combined molecular and in silico approach for the evaluation of putative disease-causing mutations contributes to the interpretation of the potential pathogenicity of these novel variants. © 2011 The Authors Annals of Human Genetics © 2011 Blackwell Publishing Ltd/University College London.
53.
Striano ; Busolin ; Santulli ; Leonardi ; Coppola ; Vitiello ; Rigon ; Michelucci ; Tosatto ; Striano ; Nobile
Familial temporal lobe epilepsy with psychic auras associated with a novel LGI1 mutation Journal Article
In: Neurology, vol. 76, no. 13, pp. 1173-1176, 2011, (Cited by: 44).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:79954525041,
title = {Familial temporal lobe epilepsy with psychic auras associated with a novel LGI1 mutation},
author = {Striano and Busolin and Santulli and Leonardi and Coppola and Vitiello and Rigon and Michelucci and Tosatto and Striano and Nobile},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-79954525041&origin=inward},
doi = {10.1212/WNL.0b013e318212ab2e},
year = {2011},
date = {2011-01-01},
journal = {Neurology},
volume = {76},
number = {13},
pages = {1173-1176},
publisher = {Lippincott Williams and Wilkins},
abstract = {Background: Autosomal dominant lateral temporal epilepsy (ADLTE) is characterized by focal seizures with auditory features or aphasia. Mutations in the LGI1 gene have been reported in up to 50% of ADLTE pedigrees. We report a family with temporal lobe epilepsy characterized by psychic symptoms associated with a novel LGI1 mutation. Methods: All participants were personally interviewed and underwent neurologic examination and video-EEG recordings. LGI1 exons were sequenced by standard methods. Mutant cDNA was transfected into human embryonic kidney 293 cells; both cell lysates and media were analyzed by Western blot. In silico modeling of the Lgi1 protein EPTP domain was carried out using the structure of WD repeat protein and manually refined. Results: Three affected family members were ascertained, 2 of whom had temporal epilepsy with psychic symptoms (déjà vu, fear) but no auditory or aphasic phenomena, while the third had complex partial seizures without any aura. In all patients, we found a novel LGI1 mutation, Arg407Cys, which did not hamper protein secretion in vitro. Mapping of the mutation on a 3-dimensional protein model showed that this mutation does not induce large structural rearrangements but could destabilize interactions of Lgi1 with target proteins. Conclusions: The Arg407Cys is the first mutation with no effect on Lgi1 protein secretion. The uncommon, isolated psychic symptoms associated with it suggests that ADLTE encompasses a wider range of auras of temporal origin than hitherto reported. © 2011 by AAN Enterprises, Inc. All rights reseved.},
note = {Cited by: 44},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: Autosomal dominant lateral temporal epilepsy (ADLTE) is characterized by focal seizures with auditory features or aphasia. Mutations in the LGI1 gene have been reported in up to 50% of ADLTE pedigrees. We report a family with temporal lobe epilepsy characterized by psychic symptoms associated with a novel LGI1 mutation. Methods: All participants were personally interviewed and underwent neurologic examination and video-EEG recordings. LGI1 exons were sequenced by standard methods. Mutant cDNA was transfected into human embryonic kidney 293 cells; both cell lysates and media were analyzed by Western blot. In silico modeling of the Lgi1 protein EPTP domain was carried out using the structure of WD repeat protein and manually refined. Results: Three affected family members were ascertained, 2 of whom had temporal epilepsy with psychic symptoms (déjà vu, fear) but no auditory or aphasic phenomena, while the third had complex partial seizures without any aura. In all patients, we found a novel LGI1 mutation, Arg407Cys, which did not hamper protein secretion in vitro. Mapping of the mutation on a 3-dimensional protein model showed that this mutation does not induce large structural rearrangements but could destabilize interactions of Lgi1 with target proteins. Conclusions: The Arg407Cys is the first mutation with no effect on Lgi1 protein secretion. The uncommon, isolated psychic symptoms associated with it suggests that ADLTE encompasses a wider range of auras of temporal origin than hitherto reported. © 2011 by AAN Enterprises, Inc. All rights reseved.
2010
54.
Benetti E; Caridi G; Malaventura C; Dagnino M; Leonardi E; Artifoni L; Ghiggeri G M; Tosatto S C E; Murer L
A novel WT1 gene mutation in a three-generation family with progressive isolated focal segmental glomerulosclerosis Journal Article
In: Clinical Journal of the American Society of Nephrology, vol. 5, no. 4, pp. 698-702, 2010, (Cited by: 35).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:77950937930,
title = {A novel WT1 gene mutation in a three-generation family with progressive isolated focal segmental glomerulosclerosis},
author = {Elisa Benetti and Gianluca Caridi and Cristina Malaventura and Monica Dagnino and Emanuela Leonardi and Lina Artifoni and Gian Marco Ghiggeri and Silvio C. E. Tosatto and Luisa Murer},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-77950937930&origin=inward},
doi = {10.2215/CJN.05670809},
year = {2010},
date = {2010-01-01},
journal = {Clinical Journal of the American Society of Nephrology},
volume = {5},
number = {4},
pages = {698-702},
abstract = {Background and objectives: Wilms tumor-suppressor gene-1 (WT1) plays a key role in kidney development and function. WT1 mutations usually occur in exons 8 and 9 and are associated with Denys-Drash, or in intron 9 and are associated with Frasier syndrome. However, overlapping clinical and molecular features have been reported. Few familial cases have been described, with intrafamilial variability. Sporadic cases of WT1 mutations in isolated diffuse mesangial sclerosis or focal segmental glomerulosclerosis have also been reported. Design, setting, participants, & measurements: Molecular analysis of WT1 exons 8 and 9 was carried out in five members on three generations of a family with late-onset isolated proteinuria. The effect of the detected amino acid substitution on WT1 protein's structure was studied by bioinformatics tools. Results: Three family members reached end-stage renal disease in full adulthood. None had genital abnormalities or Wilms tumor. Histologic analysis in two subjects revealed focal segmental glomerulosclerosis. The novel sequence variant c. 1208G > A in WT1 exon 9 was identified in all of the affected members of the family. Conclusions: The lack of Wilms tumor or other related phenotypes suggests the expansion of WT1 gene analysis in patients with focal segmental glomerulosclerosis, regardless of age or presence of typical Denys-Drash or Frasier syndrome clinical features. Structural analysis of the mutated protein revealed that the mutation hampers zinc finger-DNA interactions, impairing target gene transcription. This finding opens up new issues about WT1 function in the maintenance of the complex gene network that regulates normal podocyte function. copyright © 2010 by the American Society of Nephrology.},
note = {Cited by: 35},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background and objectives: Wilms tumor-suppressor gene-1 (WT1) plays a key role in kidney development and function. WT1 mutations usually occur in exons 8 and 9 and are associated with Denys-Drash, or in intron 9 and are associated with Frasier syndrome. However, overlapping clinical and molecular features have been reported. Few familial cases have been described, with intrafamilial variability. Sporadic cases of WT1 mutations in isolated diffuse mesangial sclerosis or focal segmental glomerulosclerosis have also been reported. Design, setting, participants, & measurements: Molecular analysis of WT1 exons 8 and 9 was carried out in five members on three generations of a family with late-onset isolated proteinuria. The effect of the detected amino acid substitution on WT1 protein’s structure was studied by bioinformatics tools. Results: Three family members reached end-stage renal disease in full adulthood. None had genital abnormalities or Wilms tumor. Histologic analysis in two subjects revealed focal segmental glomerulosclerosis. The novel sequence variant c. 1208G > A in WT1 exon 9 was identified in all of the affected members of the family. Conclusions: The lack of Wilms tumor or other related phenotypes suggests the expansion of WT1 gene analysis in patients with focal segmental glomerulosclerosis, regardless of age or presence of typical Denys-Drash or Frasier syndrome clinical features. Structural analysis of the mutated protein revealed that the mutation hampers zinc finger-DNA interactions, impairing target gene transcription. This finding opens up new issues about WT1 function in the maintenance of the complex gene network that regulates normal podocyte function. copyright © 2010 by the American Society of Nephrology.
55.
Pourová R; Janoušek P; Jurovčík M; Dvořáková M; Malíková M; Rašková D; Bendová O; Leonardi E; Murgia A; Kabelka Z; Astl J; Seeman P
Spectrum and frequency of SLC26A4 mutations among czech patients with early hearing loss with and without enlarged vestibular aqueduct (EVA) Journal Article
In: Annals of Human Genetics, vol. 74, no. 4, pp. 299-307, 2010, (Cited by: 37).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:77954780222,
title = {Spectrum and frequency of SLC26A4 mutations among czech patients with early hearing loss with and without enlarged vestibular aqueduct (EVA)},
author = {Radka Pourová and Petr Janoušek and Michal Jurovčík and Marcela Dvořáková and Marcela Malíková and Dagmar Rašková and Olga Bendová and Emanuela Leonardi and Alessandra Murgia and Zdenek Kabelka and Jaromír Astl and Pavel Seeman},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-77954780222&origin=inward},
doi = {10.1111/j.1469-1809.2010.00581.x},
year = {2010},
date = {2010-01-01},
journal = {Annals of Human Genetics},
volume = {74},
number = {4},
pages = {299-307},
abstract = {Summary: Mutations in SLC26A4 cause Pendred syndrome (PS) - hearing loss with goitre - or DFNB4 - non-syndromic hearing loss (NSHL) with inner ear abnormalities such as Enlarged Vestibular Aqueduct (EVA) or Mondini Dysplasia (MD). We tested 303 unrelated Czech patients with early hearing loss (298 with NSHL and 5 with PS), all GJB2-negative, for SLC26A4 mutations and evaluated their clinical and radiological phenotype. Among 115 available HRCT/MRI scans we detected three MD (2.6%), three Mondini-like affections (2.6%), 16 EVA (13 bilateral - 19.2% and 15.6% respectively) and 61 EVA/MD-negative scans (73.4%). We found mutation(s) in 26 patients (8.6%) and biallelic mutations in eight patients (2.7%) out of 303 tested. In 18 of 26 (69%) patients, no second mutation could be detected even using MLPA. The spectrum of SLC26A4 mutations in Czech patients is broad without any prevalent mutation. We detected 21 different mutations (four novel). The most frequent mutations were p.Val138Phe and p.Leu445Trp (18% and 8.9% of pathogenic alleles respectively). Among 13 patients with bilateral EVA, six patients (50%) carry biallelic mutations. In EVA -negative patients no biallelic mutations were found but 4.9% had monoallelic mutations. SLC26A4 mutations are present mostly in patients with EVA/MD and/or progressive HL and those with affected siblings. © 2010 The Authors Journal compilation.},
note = {Cited by: 37},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Summary: Mutations in SLC26A4 cause Pendred syndrome (PS) – hearing loss with goitre – or DFNB4 – non-syndromic hearing loss (NSHL) with inner ear abnormalities such as Enlarged Vestibular Aqueduct (EVA) or Mondini Dysplasia (MD). We tested 303 unrelated Czech patients with early hearing loss (298 with NSHL and 5 with PS), all GJB2-negative, for SLC26A4 mutations and evaluated their clinical and radiological phenotype. Among 115 available HRCT/MRI scans we detected three MD (2.6%), three Mondini-like affections (2.6%), 16 EVA (13 bilateral – 19.2% and 15.6% respectively) and 61 EVA/MD-negative scans (73.4%). We found mutation(s) in 26 patients (8.6%) and biallelic mutations in eight patients (2.7%) out of 303 tested. In 18 of 26 (69%) patients, no second mutation could be detected even using MLPA. The spectrum of SLC26A4 mutations in Czech patients is broad without any prevalent mutation. We detected 21 different mutations (four novel). The most frequent mutations were p.Val138Phe and p.Leu445Trp (18% and 8.9% of pathogenic alleles respectively). Among 13 patients with bilateral EVA, six patients (50%) carry biallelic mutations. In EVA -negative patients no biallelic mutations were found but 4.9% had monoallelic mutations. SLC26A4 mutations are present mostly in patients with EVA/MD and/or progressive HL and those with affected siblings. © 2010 The Authors Journal compilation.
56.
Brini M; Leva F D; Ortega C K; Domi T; Ottolini D; Leonardi E; Tosatto S C E; Carafoli E
Deletions and mutations in the acidic lipid-binding region of the plasma membrane Ca2+ pump: A study on different splicing variants of isoform 2 Journal Article
In: Journal of Biological Chemistry, vol. 285, no. 40, pp. 30779-30791, 2010, (Cited by: 22; Open Access).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:77957277448,
title = {Deletions and mutations in the acidic lipid-binding region of the plasma membrane Ca2+ pump: A study on different splicing variants of isoform 2},
author = {Marisa Brini and Francesca Di Leva and Claudia K. Ortega and Teuta Domi and Denis Ottolini and Emanuela Leonardi and Silvio C. E. Tosatto and Ernesto Carafoli},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-77957277448&origin=inward},
doi = {10.1074/jbc.M110.140475},
year = {2010},
date = {2010-01-01},
journal = {Journal of Biological Chemistry},
volume = {285},
number = {40},
pages = {30779-30791},
publisher = {American Society for Biochemistry and Molecular Biology Inc.9650 Rockville PikeBethesdaMD 20814},
abstract = {Acidic phospholipids increase the affinity of the plasma membrane Ca 2+-ATPase pump for Ca2+. They interact with the C-terminal region of the pump and with a domain in the loop connecting transmembrane domains 2 and 3 (AL region) next to site A of alternative splicing. The contribution of the two phospholipid-binding sites and the possible interference of splicing inserts at site A with the regulation of the ATPase activity of isoform 2 of the pump by phospholipids have been analyzed. The activity of the full-length z/b variant (no insert at site A), the w/b (with insert at site A), and the w/a variant, containing both the 45-amino acid A-site insert and a C-site insert that truncates the pump in the calmodulin binding domain, has been analyzed in microsomal membranes of overexpressing CHO cells. The A-site insertion did not modify the phospholipid sensitivity of the pump, but the doubly inserted w/a variant became insensitive to acidic phospholipids, even if containing the intact AL phospholipid binding domain. Pump mutants in which 12 amino acids had been deleted, or single lysine mutations introduced, in the AL region were studied by monitoring agonist-induced Ca2+ transients in overexpressing CHO cells. The 12-residue deletion completely abolished the ATPase activity of the w/a variant but only reduced that of the z/b variant, which was also affected by the single lysine substitutions in the same domain. A structural interpretation of the interplay of the pump with phospholipids, and of the mechanism of their activation, is proposed on the basis of molecular modeling studies. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.},
note = {Cited by: 22; Open Access},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Acidic phospholipids increase the affinity of the plasma membrane Ca 2+-ATPase pump for Ca2+. They interact with the C-terminal region of the pump and with a domain in the loop connecting transmembrane domains 2 and 3 (AL region) next to site A of alternative splicing. The contribution of the two phospholipid-binding sites and the possible interference of splicing inserts at site A with the regulation of the ATPase activity of isoform 2 of the pump by phospholipids have been analyzed. The activity of the full-length z/b variant (no insert at site A), the w/b (with insert at site A), and the w/a variant, containing both the 45-amino acid A-site insert and a C-site insert that truncates the pump in the calmodulin binding domain, has been analyzed in microsomal membranes of overexpressing CHO cells. The A-site insertion did not modify the phospholipid sensitivity of the pump, but the doubly inserted w/a variant became insensitive to acidic phospholipids, even if containing the intact AL phospholipid binding domain. Pump mutants in which 12 amino acids had been deleted, or single lysine mutations introduced, in the AL region were studied by monitoring agonist-induced Ca2+ transients in overexpressing CHO cells. The 12-residue deletion completely abolished the ATPase activity of the w/a variant but only reduced that of the z/b variant, which was also affected by the single lysine substitutions in the same domain. A structural interpretation of the interplay of the pump with phospholipids, and of the mechanism of their activation, is proposed on the basis of molecular modeling studies. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.
2009
57.
Leonardi ; Murgia ; Tosatto
Adding structural information to the von Hippel-Lindau (VHL) tumor suppressor interaction network Journal Article
In: FEBS Letters, vol. 583, no. 22, pp. 3704-3710, 2009, (Cited by: 22).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:71749098721,
title = {Adding structural information to the von Hippel-Lindau (VHL) tumor suppressor interaction network},
author = {Leonardi and Murgia and Tosatto},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-71749098721&origin=inward},
doi = {10.1016/j.febslet.2009.10.070},
year = {2009},
date = {2009-01-01},
journal = {FEBS Letters},
volume = {583},
number = {22},
pages = {3704-3710},
abstract = {The von Hippel-Lindau (VHL) tumor suppressor gene is a protein interaction hub, controlling numerous genes implicated in tumor progression. Here we focus on structural aspects of protein interactions for a list of 35 experimentally verified protein VHL (pVHL) interactors. Using structural information and computational analysis we have located three distinct interaction interfaces (A, B, and C). Interface B is the most versatile, recognizing a refined linear motif present in 17 otherwise non-related proteins. It has been possible to distinguish compatible and exclusive interactions by relating pVHL function to interaction interfaces and subcellular localization. A novel hypothesis is presented regarding the possible function of the N-terminus as an inhibitor of pVHL function. © 2009 Federation of European Biochemical Societies.},
note = {Cited by: 22},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The von Hippel-Lindau (VHL) tumor suppressor gene is a protein interaction hub, controlling numerous genes implicated in tumor progression. Here we focus on structural aspects of protein interactions for a list of 35 experimentally verified protein VHL (pVHL) interactors. Using structural information and computational analysis we have located three distinct interaction interfaces (A, B, and C). Interface B is the most versatile, recognizing a refined linear motif present in 17 otherwise non-related proteins. It has been possible to distinguish compatible and exclusive interactions by relating pVHL function to interaction interfaces and subcellular localization. A novel hypothesis is presented regarding the possible function of the N-terminus as an inhibitor of pVHL function. © 2009 Federation of European Biochemical Societies.
2006
58.
Casarin A; Martella M; Polli R; Leonardi E; Anesi L; Murgia A
In: Molecular Diagnosis and Therapy, vol. 10, no. 4, pp. 243-249, 2006, (Cited by: 24).
Abstract | Links | Altmetric | Dimensions | PlumX
@article{SCOPUS_ID:33747123661,
title = {Molecular characterization of large deletions in the von Hippel-Lindau (VHL) gene by quantitative real-time PCR: The hypothesis of an Alu-mediated mechanism underlying VHL gene rearrangements},
author = {Alberto Casarin and Maddalena Martella and Roberta Polli and Emanuela Leonardi and Laura Anesi and Alessandra Murgia},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-33747123661&origin=inward},
doi = {10.1007/BF03256463},
year = {2006},
date = {2006-01-01},
journal = {Molecular Diagnosis and Therapy},
volume = {10},
number = {4},
pages = {243-249},
publisher = {Adis International Ltd},
abstract = {Introduction: Mutations of the von Hippel-Lindau (VHL) gene are responsible for VHL disease. This is a familial autosomal-dominant syndrome, predisposing to the development of benign and malignant tumors, including CNS and retinal hemangioblastomas, pheochromocytomas, and clear cell renal carcinomas. At least 30% of the disease-causing mutations in the VHL gene involve large alterations. Identification of these mutations is not possible using PCR-based mutational scanning methods. Quantitative Southern blot analysis has been traditionally employed for the detection of complete or partial deletions and more complex rearrangements of the gene. Methods: An alternative quantitative method was developed using a combination of quantitative Southern blot analysis and real-time PCR. With this approach, we studied 24 large VHL gene alterations to determine the exact nature of the mutations and to possibly characterize the boundaries of the deleted regions. Results: This combined molecular approach showed that all the VHL alterations studied were due to deletions, from which the position in the gene could be more precisely mapped. One of the samples that was completely characterized was found to carry an intragenic 2.2kb deletion with both 5′ and 3′ breakpoints located within Alu-repeat sequences. Conclusion: This is the first report on the molecular analysis of large VHL alterations. The results of our study and the complete characterization of a large deletion lead to the hypothesis that an Alu-mediated mechanism may be responsible for the common occurrence of large alterations in the VHL gene. © 2006 Adis Data Information BV. All rights reserved.},
note = {Cited by: 24},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Introduction: Mutations of the von Hippel-Lindau (VHL) gene are responsible for VHL disease. This is a familial autosomal-dominant syndrome, predisposing to the development of benign and malignant tumors, including CNS and retinal hemangioblastomas, pheochromocytomas, and clear cell renal carcinomas. At least 30% of the disease-causing mutations in the VHL gene involve large alterations. Identification of these mutations is not possible using PCR-based mutational scanning methods. Quantitative Southern blot analysis has been traditionally employed for the detection of complete or partial deletions and more complex rearrangements of the gene. Methods: An alternative quantitative method was developed using a combination of quantitative Southern blot analysis and real-time PCR. With this approach, we studied 24 large VHL gene alterations to determine the exact nature of the mutations and to possibly characterize the boundaries of the deleted regions. Results: This combined molecular approach showed that all the VHL alterations studied were due to deletions, from which the position in the gene could be more precisely mapped. One of the samples that was completely characterized was found to carry an intragenic 2.2kb deletion with both 5′ and 3′ breakpoints located within Alu-repeat sequences. Conclusion: This is the first report on the molecular analysis of large VHL alterations. The results of our study and the complete characterization of a large deletion lead to the hypothesis that an Alu-mediated mechanism may be responsible for the common occurrence of large alterations in the VHL gene. © 2006 Adis Data Information BV. All rights reserved.
2005
59.
Castillo D; Rodríguez-Ballesteros ; Álvarez ; Hutchin ; Leonardi ; Oliveira D; Azaiez ; Brownstein ; Avenarius ; Marlin ; Pandya ; Shahin ; Siemering ; Weil ; Wuyts ; Aguirre ; Marlín ; Moreno-Pelayo ; Villamar ; Avraham ; Dahl ; Kanaan ; Nance ; Petit ; Smith ; Camp V; Sartorato ; Murgia ; Moreno ; Castillo I D
In: Journal of Medical Genetics, vol. 42, no. 7, pp. 588-594, 2005, (Cited by: 284; Open Access).
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@article{SCOPUS_ID:22244489070,
title = {A novel deletion involving the connexin-30 gene, del(GJB6-d13s1854), found in trans with mutations in the GJB2 gene (connexin-26) in subjects with DFNB1 non-syndromic hearing impairment},
author = {Del Castillo and Rodríguez-Ballesteros and Álvarez and Hutchin and Leonardi and De Oliveira and Azaiez and Brownstein and Avenarius and Marlin and Pandya and Shahin and Siemering and Weil and Wuyts and Aguirre and Marlín and Moreno-Pelayo and Villamar and Avraham and Dahl and Kanaan and Nance and Petit and Smith and Van Camp and Sartorato and Murgia and Moreno and Ignacio Del Castillo},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-22244489070&origin=inward},
doi = {10.1136/jmg.2004.028324},
year = {2005},
date = {2005-01-01},
journal = {Journal of Medical Genetics},
volume = {42},
number = {7},
pages = {588-594},
abstract = {DFNB1 deafness, caused by mutations in the gene encoding connexin-26 (GJB2), is the most frequent subtype of autosomal recessive non-syndromic hearing impairment. Molecular testing for GJB2 mutations has become a standard diagnostic approach for subjects with this disorder. However, 10-50% of affected subjects with GJB2 mutations carry only one mutant allele. A 309 kb deletion truncating the GJB6 gene (encoding connexin-30) was shown to be the accompanying mutation in up to 50% of deaf GJB2 heterozygotes in different populations. We report the molecular characterisation of the breakpoint junction of a novel 232 kb deletion in the DFNB1 locus, del(GJB6-D13S1854), which was also found in trans with pathogenic GJB2 mutations in affected subjects. The deletion arose by unequal homologous recombination, involving an AluY sequence inside GJB6 intron 2, a mechanism which might generate other deletions at DFNB1. We developed a novel diagnostic test for the combined detection of del(GJB6-D13S1830) and this new del(GJB6-D13S1854) in a single PCR assay. The del(GJB6-D13S1854) mutation accounts for 25.5% of the affected GJB2 heterozygotes which remained unresolved after screening for del(GJB6-D13S1830) in Spain, 22.2% in the UK, 6.3% in Brazil and 1.9% in northern Italy. It was not found in affected GJB2 heterozygotes from France, Belgium, Israel, the Palestinian Authority, USA, or Australia. Haplotype analysis revealed a common founder for the mutation in Spain, Italy, and the UK. Our data further support the complexity the genetic epidemiology of non-syndromic hearing impairment.},
note = {Cited by: 284; Open Access},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
DFNB1 deafness, caused by mutations in the gene encoding connexin-26 (GJB2), is the most frequent subtype of autosomal recessive non-syndromic hearing impairment. Molecular testing for GJB2 mutations has become a standard diagnostic approach for subjects with this disorder. However, 10-50% of affected subjects with GJB2 mutations carry only one mutant allele. A 309 kb deletion truncating the GJB6 gene (encoding connexin-30) was shown to be the accompanying mutation in up to 50% of deaf GJB2 heterozygotes in different populations. We report the molecular characterisation of the breakpoint junction of a novel 232 kb deletion in the DFNB1 locus, del(GJB6-D13S1854), which was also found in trans with pathogenic GJB2 mutations in affected subjects. The deletion arose by unequal homologous recombination, involving an AluY sequence inside GJB6 intron 2, a mechanism which might generate other deletions at DFNB1. We developed a novel diagnostic test for the combined detection of del(GJB6-D13S1830) and this new del(GJB6-D13S1854) in a single PCR assay. The del(GJB6-D13S1854) mutation accounts for 25.5% of the affected GJB2 heterozygotes which remained unresolved after screening for del(GJB6-D13S1830) in Spain, 22.2% in the UK, 6.3% in Brazil and 1.9% in northern Italy. It was not found in affected GJB2 heterozygotes from France, Belgium, Israel, the Palestinian Authority, USA, or Australia. Haplotype analysis revealed a common founder for the mutation in Spain, Italy, and the UK. Our data further support the complexity the genetic epidemiology of non-syndromic hearing impairment.
2004
60.
Cryns ; Orzan ; Murgia ; Huygen ; Moreno ; Castillo D; Chamberlin P; Azaiez ; Prasad ; Cucci ; Leonardi ; Snoeckx ; Govaerts ; Heyning V D; Heyning V D; Smith ; Camp V
A genotype-phenotype correlation for GJB2 (connexin 26) deafness Journal Article
In: Journal of Medical Genetics, vol. 41, no. 3, pp. 147-154, 2004, (Cited by: 194; Open Access).
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@article{SCOPUS_ID:12144287717,
title = {A genotype-phenotype correlation for GJB2 (connexin 26) deafness},
author = {Cryns and Orzan and Murgia and Huygen and Moreno and Del Castillo and Parker Chamberlin and Azaiez and Prasad and Cucci and Leonardi and Snoeckx and Govaerts and Van De Heyning and Van De Heyning and Smith and Van Camp},
url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-12144287717&origin=inward},
doi = {10.1136/jmg.2003.013896},
year = {2004},
date = {2004-01-01},
journal = {Journal of Medical Genetics},
volume = {41},
number = {3},
pages = {147-154},
publisher = {BMJ Publishing Group},
abstract = {Introduction: Mutations in GJB2 are the most common cause of non-syndromic autosomal recessive hearing impairment, ranging from mild to profound. Mutation analysis of this gene is widely available as a genetic diagnostic test. Objective: To assess a possible genotype-phenotype correlation for GJB2. Design: Retrospective analysis of audiometric data from people with hearing impairment, segregating two GJB2 mutations. Subjects: Two hundred and seventy seven unrelated patients with hearing impairment who were seen at the ENT departments of local and university hospitals from Italy, Belgium, Spain, and the United States, and who harboured bi-allelic GJB2 mutations. Results: We found that 35delG homozygotes have significantly more hearing impairment, compared with 35delG/non-35delG compound heterozygotes. People with two non-35delG mutations have even less hearing impairment. We observed a similar gradient of hearing impairment when we categorised mutations as inactivating (that is, stop mutations or frame shifts) or non-inactivating (that is, missense mutations). We demonstrated that certain mutation combinations (including the combination of 35delG with the missense mutations L90P, V37I, or the splice-site mutation IVS1+1G>A, and the V37I/V37I genotype) are associated with significantly less hearing impairment compared with 35delG homozygous genotypes. Conclusions: This study is the first large systematic analysis indicating that the GJB2 genotype has a major impact on the degree of hearing impairment, and identifying mild genotypes. Furthermore, this study shows that it will be possible to refine this correlation and extend it to additional genotypes. These data will be useful in evaluating habilitation options for people with GJB2 related deafness.},
note = {Cited by: 194; Open Access},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Introduction: Mutations in GJB2 are the most common cause of non-syndromic autosomal recessive hearing impairment, ranging from mild to profound. Mutation analysis of this gene is widely available as a genetic diagnostic test. Objective: To assess a possible genotype-phenotype correlation for GJB2. Design: Retrospective analysis of audiometric data from people with hearing impairment, segregating two GJB2 mutations. Subjects: Two hundred and seventy seven unrelated patients with hearing impairment who were seen at the ENT departments of local and university hospitals from Italy, Belgium, Spain, and the United States, and who harboured bi-allelic GJB2 mutations. Results: We found that 35delG homozygotes have significantly more hearing impairment, compared with 35delG/non-35delG compound heterozygotes. People with two non-35delG mutations have even less hearing impairment. We observed a similar gradient of hearing impairment when we categorised mutations as inactivating (that is, stop mutations or frame shifts) or non-inactivating (that is, missense mutations). We demonstrated that certain mutation combinations (including the combination of 35delG with the missense mutations L90P, V37I, or the splice-site mutation IVS1+1G>A, and the V37I/V37I genotype) are associated with significantly less hearing impairment compared with 35delG homozygous genotypes. Conclusions: This study is the first large systematic analysis indicating that the GJB2 genotype has a major impact on the degree of hearing impairment, and identifying mild genotypes. Furthermore, this study shows that it will be possible to refine this correlation and extend it to additional genotypes. These data will be useful in evaluating habilitation options for people with GJB2 related deafness.