Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2004-8-31
pubmed:abstractText
Homozygous deletion or mutation in the survival motor neuron (SMN)1 gene causes proximal spinal muscular atrophy (SMA), whereas SMN2 acts as a modifying gene that can influence the severity of SMA. It has been suggested that restoration of the SMN protein level in neuronal cells may prevent cell loss and may be helpful for treatment of SMA. Recent studies indicate that the ubiquitin/proteasome pathway is a major system for proteolysis of intracellular proteins. In this study, we investigate whether SMN protein is degraded via the ubiquitin/proteasome pathway. Primary fibroblasts were established from the skin biopsies of SMA patients and the effect of a proteasome inhibitor MG132 and lysosome inhibitor NH(4)Cl on SMN protein level was examined. We found that MG132, but not NH(4)Cl, significantly increased the amount and nuclear accumulation of SMN protein in SMA patient's fibroblasts. Immunoprecipitation/western blot analysis indicated that SMN protein was ubiquitinated in cells. In vitro protein ubiquitination assay also demonstrated that SMN protein could be conjugated with ubiquitin. Taken together, we have provided clear evidences that degradation of SMN protein is mediated via the ubiquitin/proteasome pathway and suggest that proteasome inhibitors may up-regulate SMN protein level and may be useful for the treatment of SMA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Cyclic AMP Response..., http://linkedlifedata.com/resource/pubmed/chemical/Cysteine Endopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/Leupeptins, http://linkedlifedata.com/resource/pubmed/chemical/Multienzyme Complexes, http://linkedlifedata.com/resource/pubmed/chemical/Nerve Tissue Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Proteasome Endopeptidase Complex, http://linkedlifedata.com/resource/pubmed/chemical/RNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/SMN Complex Proteins, http://linkedlifedata.com/resource/pubmed/chemical/SMN2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Survival of Motor Neuron 2 Protein, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitin, http://linkedlifedata.com/resource/pubmed/chemical/benzyloxycarbonylleucyl-leucyl-leuci...
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0197-0186
pubmed:author
pubmed:issnType
Print
pubmed:volume
45
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1107-12
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Degradation of survival motor neuron (SMN) protein is mediated via the ubiquitin/proteasome pathway.
pubmed:affiliation
Department of Physiology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't