Molecular mechanism for distinct neurological phenotypes conveyed by allelic truncating mutations.
The molecular mechanisms by which different mutations in the same gene can result in distinct disease phenotypes remain largely unknown. Truncating mutations of SOX10 cause either a complex neurocristopathy designated PCWH or a more restricted phenotype known as Waardenburg-Shah syndrome (WS4; OMIM 277580). Here we report that although all nonsense and frameshift mutations that cause premature termination of translation generate truncated SOX10 proteins with potent dominant-negative activity, the more severe disease phenotype, PCWH, is realized only when the mutant mRNAs escape the nonsense-mediated decay (NMD) pathway. We observe similar results for truncating mutations of MPZ that convey distinct myelinopathies. Our experiments show that triggering NMD and escaping NMD may cause distinct neurological phenotypes.
Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Room 604B, Houston, Texas 77030, USA.
Ken
K
Inoue
Mehrdad
M
Khajavi
Tomoko
T
Ohyama
Shin-ichi
S
Hirabayashi
John
J
Wilson
James D
JD
Reggin
Pedro
P
Mancias
Ian J
IJ
Butler
Miles F
MF
Wilkinson
Michael
M
Wegner
James R
JR
Lupski
D000483:Alleles; D004268:DNA-Binding Proteins / Q000235:genetics; D015536:Down-Regulation; D006609:High Mobility Group Proteins / Q000235:genetics; D006801:Humans; D009154:Mutation; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics; D055757:SOXE Transcription Factors; D014157:Transcription Factors
D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; D012333:RNA, Messenger; C527923:SOX10 protein, human; D055757:SOXE Transcription Factors; D014157:Transcription Factors