@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}

}

@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}

}

@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}

}

@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: 278; Open Access},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@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: 192; Open Access},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{SCOPUS_ID:0038270170,

title = {Connexin 26 35delG does not represent a mutational hotspot},

author = {Caryn R. Rothrock and Alessandra Murgia and Edi L. Sartorato and Emanuela Leonardi and Sainan Wei and Sarah L. Lebeis and Laura E. Yu and Jill L. Elfenbein and Rachel A. Fisher and Karen H. Friderici},

url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-0038270170&origin=inward},

doi = {10.1007/s00439-003-0944-2},

year  = {2003},

date = {2003-01-01},

journal = {Human Genetics},

volume = {113},

number = {1},

pages = {18-23},

publisher = {Springer Verlag},

abstract = {Non-syndromic hearing impairment (NSHI) is the most common form of deafness and presents with no other symptoms or sensory defects. Mutations in the gap junction gene GJB2 account for a high proportion of recessive NSHI. The GJB2 gene encodes connexin 26, which forms plasma membrane channels between cochlear cells. In Caucasian populations a single mutation, 35delG, accounts for most cases of NSHI. This mutation appears to be most prevalent in individuals of Mediterranean European descent, with carrier frequencies estimated as being as high as one in thirty. The 35delG region may be a mutational hotspot. The mutation arises from the deletion of a guanine from a six-guanine stretch and nearby microsatellite markers show little evidence for linkage disequilibrium. We believe that 35delG is an old mutation in a chromosomal region of high recombination. The genetic context of the 35delG mutation was examined to distinguish between an old or a recurring mutation. We identified two single-nucleotide polymorphisms (SNPs) immediately upstream of the first exon of GJB2. Polymerase chain reaction/restriction fragment length polymorphism analysis determined the SNP genotype of 35delG containing chromosomes from various populations, including Italy, Brazil, and North America. We found the same, relatively rare, polymorphism associated with the 35delG mutation in all populations studied. We have also examined microsatellite markers D13S175, which is 80kb telomeric to GJB2, and D13S1316, which is 80kb centromeric to GJB2. D13S175 appears to be in weak linkage disequilibrium with 35delG, while D13S1316 is less so. SNPs located between the 35delG mutation and the microsatellite markers show strong evidence of linkage disequilibrium. Taken together, these results indicate there has been substantial recombination near the 35delG mutation; however, we present evidence that the 35delG mutation arose in European and Middle Eastern populations from a single mutational event on a founder chromosome. © Springer-Verlag 2003.},

note = {Cited by: 48},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{SCOPUS_ID:0032727332,

title = {Cx26 deafness: Mutation analysis and clinical variability},

author = {Murgia and Orzan and Polli and Martella and Vinanzi and Leonardi and Arslan and Zacchello},

url = {https://www.scopus.com/record/display.uri?eid=2-s2.0-0032727332&origin=inward},

doi = {10.1136/jmg.36.11.829},

year  = {1999},

date = {1999-01-01},

journal = {Journal of Medical Genetics},

volume = {36},

number = {11},

pages = {829-832},

publisher = {BMJ Publishing Group},

abstract = {Mutations in the gap junction protein connexin 26 (Cx26) gene (GJB2) seem to account for many cases of congenital sensorineural hearing impairment, the reported prevalence being 34-50% in autosomal recessive cases and 10-37% in sporadic cases. The hearing impairment in these patients has been described as severe or profound. We have studied 53 unrelated subjects with congenital non-syndromic sensorineural hearing impairment in order to evaluate the prevalence and type of Cx26 mutations and establish better genotype-phenotype correlation. Mutations in the Cx26 gene were found in 53% of the subjects tested, 35.3% of the autosomal recessive and 60% of the sporadic cases in our series. Three new mutations were identified. The hearing deficit varied from mild to profound even in 35delG homozygotes within the same family. No evidence of progression of the impairment was found. Alterations of the Cx26 gene account for a large proportion of cases of congenital non-syndromic sensorineural deafness, so it seems appropriate to extend the molecular analysis even to subjects with mild or moderate prelingual hearing impairment of unknown cause.},

note = {Cited by: 127; Open Access},

keywords = {},

pubstate = {published},

tppubtype = {article}

}