Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2008-5-1
pubmed:abstractText
Missense mutations are not considered a common cause of type 3 von Willebrand's disease (VWD), the most severe defect of von Willebrand factor (VWF) characterized by undetectable levels of this protein in plasma and platelets. Nevertheless, several missense mutations have been identified in these patients. In this study, we report the cases of two Italian patients with type 3 VWD, both compound heterozygotes for different missense mutations and null alleles, p.D141Y/c.2016_2019del and p.C275S/p.W222X. We performed in vitro expression studies of the candidate missense mutations, both located in the D1 domain of VWF propeptide, to confirm their link with the disease and to understand the mechanisms of type 3 VWD responsible in these patients. Mutant and wild-type (WT) expression vectors were used for transient transfection and co-transfection studies in COS-7 cells. Single construct transfections of both missense mutations showed a strongly reduced but detectable secretion of recombinant (r)VWFs (approximately 15% of WT), with essentially only dimers being visualized on multimeric analysis. As expected, expression of a single construct of either mutation with the WT, showed mildly reduced secretion (approximately 40% of WT) and a full set of multimers. These expression studies indicate that the two amino acids D141 and C275 are key residues in the tertiary structure of the VWF propeptide. Their replacement with a tyrosine and a serine, respectively, might compromise propeptide folding, affecting both its intracellular survival and its capacity to mediate multimerization. Co-expression of hybrid rVWFs confirmed the recessive inheritance pattern of these missense mutations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1365-2516
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
549-55
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:18328061-Adult, pubmed-meshheading:18328061-Animals, pubmed-meshheading:18328061-Blood Platelets, pubmed-meshheading:18328061-COS Cells, pubmed-meshheading:18328061-Cercopithecus aethiops, pubmed-meshheading:18328061-DNA Mutational Analysis, pubmed-meshheading:18328061-Dimerization, pubmed-meshheading:18328061-Female, pubmed-meshheading:18328061-Gene Expression, pubmed-meshheading:18328061-Heterozygote, pubmed-meshheading:18328061-Humans, pubmed-meshheading:18328061-Middle Aged, pubmed-meshheading:18328061-Mutation, Missense, pubmed-meshheading:18328061-Phenotype, pubmed-meshheading:18328061-Polymerase Chain Reaction, pubmed-meshheading:18328061-Recombinant Proteins, pubmed-meshheading:18328061-Severity of Illness Index, pubmed-meshheading:18328061-Transfection, pubmed-meshheading:18328061-von Willebrand Diseases, pubmed-meshheading:18328061-von Willebrand Factor
pubmed:year
2008
pubmed:articleTitle
Expression studies of missense mutations p.D141Y, p.C275S located in the propeptide of von Willebrand factor in patients with type 3 von Willebrand disease.
pubmed:affiliation
Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Department of Internal Medicine and Medical Specialties, Foundation IRCCS Maggiore Policlinico Hospital, Mangiagalli, Regina Elena and University of Milan, Milan, Italy. luciano.baronciani@unimi.it
pubmed:publicationType
Journal Article, In Vitro, Case Reports