Sequestosome 1 mutations in Paget's disease of bone in Australia: Prevalence, genotype/phenotype correlation and a novel non-UBA domain mutation (P364S) associated with increased NF-κB signalling without loss of ubiquitin-binding

Mutations affecting the UBA (ubiquitin-associated) domain of SQSTM1 (Sequestosome 1) (p62) are a common cause of Paget's disease of bone. The missense mutations resolve into those which retain [P392L (Pro392→Leu), G411S] or abolish (M404V, G425R) the ability of the isolated UBA domain to bind Lys-48-linked polyubiquitin. These effects can be rationalized with reference to the solution structure of the UBA domain, which we have determined by NMR spectroscopy. The UBA domain forms a characteristic compact three-helix bundle, with a hydrophobic patch equivalent to that previously implicated in ubiquitin binding by other UBA domains. None of the mutations affect overall folding of the UBA domain, but both M404V and G425R involve residues in the hydrophobic patch, whereas Pro-392 and Gly-411 are more remote. A simple model assuming the isolated UBA domain is functioning as a compact monomer can explain the effects of the mutations on polyubiquitin binding. The P392L and G411S mutations do however have subtle local effects on secondary structure, which may become more relevant in full-length SQSTM1. Identification of the in vivo ubiquitylated substrates of SQSTM1 will be most informative in determining the functional significance of the SQSTM1–ubiquitin interaction, and consequences of the disease-associated mutations.

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Functional and structural studies of two UBA domain missense mutations of sequestosome 1 (SQSTM1) in Paget's disease of bone

Bone ◽

10.1016/j.bone.2012.02.522 ◽

2012 ◽

Vol 50 ◽

pp. S166

Author(s):

A.J. Goode⁎ ◽

J. Long ◽

B. Shaw ◽

H. Williams ◽

S. Ralston ◽

...

Keyword(s):

Paget’S Disease ◽

Paget's Disease ◽

Paget’S Disease Of Bone ◽

Missense Mutations ◽

Paget's Disease Of Bone ◽

Structural Studies ◽

Sequestosome 1 ◽

Uba Domain

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p62 mutations, ubiquitin recognition and Paget's disease of bone

Biochemical Society Transactions ◽

10.1042/bst0340735 ◽

2006 ◽

Vol 34 (5) ◽

pp. 735-737 ◽

Cited By ~ 20

Author(s):

R. Layfield ◽

J.R. Cavey ◽

D. Najat ◽

J. Long ◽

P.W. Sheppard ◽

...

Keyword(s):

Paget’S Disease ◽

Adaptor Protein ◽

Paget's Disease ◽

Paget’S Disease Of Bone ◽

Host Protein ◽

Paget's Disease Of Bone ◽

Disease Mechanism ◽

Binding Function ◽

Ubiquitin Binding ◽

Uba Domain

Functional analyses of PDB (Paget's disease of bone)-associated mutants of the p62 [also known as SQSTM1 (sequestosome 1)] signalling adaptor protein represent an interesting paradigm for understanding not only the disease mechanism in this skeletal disorder, but also the critical determinants of ubiquitin recognition by an ubiquitin-binding protein. The 11 separate PDB mutations identified to date all affect the C-terminal region of p62 containing the UBA domain (ubiquitin-associated domain), a ubiquitin-binding element. All of these mutations have deleterious effects on ubiquitin binding by p62 in vitro, and there is evidence of an inverse relationship between ubiquitin-binding function and disease severity. The effects on ubiquitin-binding function of most of the mutations can be attributed to either reduced UBA domain stability, and/or the mutations affecting the presumed ubiquitin-binding interface of the UBA domain. However, a subset of the mutations are more difficult to rationalize; several of these affect sequences of p62 outside of the minimal ubiquitin-binding region, providing insights into non-UBA domain sequences within the host protein which mediate ubiquitin-binding affinity. The p62 mutations are presumed to result in activation of (osteoclast) NF-κB (nuclear factor κB) signalling. Understanding how loss of ubiquitin-binding function of p62 impacts on signal transduction events in osteoclasts will undoubtedly further our understanding of the disease mechanism in PDB at the molecular level.

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Pattern of SQSTM1 Gene Variants in a Hungarian Cohort of Paget’s Disease of Bone

Calcified Tissue International ◽

10.1007/s00223-020-00758-4 ◽

2020 ◽

Author(s):

Judit Donáth ◽

Bernadett Balla ◽

Márton Pálinkás ◽

Rita Rásonyi ◽

Gyula Vastag ◽

...

Keyword(s):

Mutation Screening ◽

Paget’S Disease ◽

Paget's Disease ◽

Paget’S Disease Of Bone ◽

Gene Variants ◽

Eastern European ◽

Paget's Disease Of Bone ◽

Genetic Studies ◽

Mutation Status ◽

Sequestosome 1

Abstract Paget’s disease of bone (PDB) is characterized by focal or multifocal increase in bone turnover. One of the most well-established candidate genes for susceptibility to PDB is Sequestosome 1 (SQSTM1). Mutations in SQSTM1 have been documented among Western-European, British and American patients with PDB. However, there is no information on SQSTM1 mutation status in PDB patients from the Central- and Eastern-European regions. In this study, we conducted a mutation screening for SQSTM1 gene variants in 82 PDB patients and 100 control participants in Hungary. Mutations of SQSTM1 were detected in 18 PDB patients (21.95%); associations between genotype and clinical characteristics were also analyzed. Altogether, six different exonic alterations, including two types of UTR variants in the SQSTM1 gene, were observed in our PDB patients. Similarly, to previous genetic studies on Paget’s disease, our most commonly detected variant was the c.1175C > T (p.Pro392Leu) in nine cases (four in monostotic and five in polyostotic form). We have surveyed the germline SQSTM1 variant distribution among Hungarian patients with PDB. We also highlighted that the pattern of the analyzed disease-associated pathophysiological parameters could partially discriminate PDB patients with normal or mutant SQSTM1 genotype. However, our findings also underline and strengthen that not solely SQSTM1 stands in the background of the complex PDB etiology.

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Loss of Ubiquitin-Binding Associated With Paget's Disease of Bone p62 (SQSTM1) Mutations

Journal of Bone and Mineral Research ◽

10.1359/jbmr.041205 ◽

2004 ◽

Vol 20 (4) ◽

pp. 619-624 ◽

Cited By ~ 78

Author(s):

James R Cavey ◽

Stuart H Ralston ◽

Lynne J Hocking ◽

Paul W Sheppard ◽

Barbara Ciani ◽

...

Keyword(s):

Paget’S Disease ◽

Paget's Disease ◽

Paget’S Disease Of Bone ◽

Paget's Disease Of Bone ◽

Ubiquitin Binding

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Molecular insights into an ancient form of Paget’s disease of bone

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1820556116 ◽

2019 ◽

Vol 116 (21) ◽

pp. 10463-10472 ◽

Cited By ~ 7

Author(s):

Barry Shaw ◽

Carla L. Burrell ◽

Darrell Green ◽

Ana Navarro-Martinez ◽

Daniel Scott ◽

...

Keyword(s):

Direct Sequencing ◽

Paget’S Disease ◽

Paget's Disease ◽

Paget’S Disease Of Bone ◽

Paget's Disease Of Bone ◽

North West ◽

Sequestosome 1 ◽

The North ◽

History Of ◽

Skeletal Samples

Paget’s disease of bone (PDB) is a chronic skeletal disorder that can affect one or several bones in individuals older than 55 y of age. PDB-like changes have been reported in archaeological remains as old as Roman, although accurate diagnosis and natural history of the disease is lacking. Six skeletons from a collection of 130 excavated at Norton Priory in the North West of England, which dates to medieval times, show atypical and extensive pathological changes resembling contemporary PDB affecting as many as 75% of individual skeletons. Disease prevalence in the remaining collection is high, at least 16% of adults, with age at death estimations as low as 35 y. Despite these atypical features, paleoproteomic analysis identified sequestosome 1 (SQSTM1) or p62, a protein central to the pathological milieu of PDB, as one of the few noncollagenous human sequences preserved in skeletal samples. Targeted proteomic analysis detected >60% of the ancient p62 primary sequence, with Western blotting indicating p62 abnormalities, including in dentition. Direct sequencing of ancient DNA excluded contemporary PDB-associated SQSTM1 mutations. Our observations indicate that the ancient p62 protein is likely modified within its C-terminal ubiquitin-associated domain. Ancient miRNAs were remarkably preserved in an osteosarcoma from a skeleton with extensive disease, with miR-16 expression consistent with that reported in contemporary PDB-associated bone tumors. Our work displays the use of proteomics to inform diagnosis of ancient diseases such as atypical PDB, which has unusual features presumably potentiated by yet-unidentified environmental or genetic factors.

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