title: Characterization of a novel missense mutation on murine Pax3 through ENU mutagenesis.
abstract: N-ethyl-N-nitrosourea (ENU) mutagenesis has led to the elucidation of several regulator genes for melanocyte and skin development. Here we characterized a mutant from ENU mutagenesis with similar phenotype as that of Splotch mutant, including exencephaly, spina bifida and abnormal limbs in homozygotes as well as white belly spotting and occasionally loop-tail in heterozygotes. This novel mutant was named as Sp(xG). Through genome-wide linkage analysis in backcross progenies with microsatellite markers, the Sp(xG) was confined to a region between D1MIT415 and D1MIT7 on chromosome 1, where notable Pax3 gene was located. Direct sequencing revealed that Sp(xG) carried a nucleotide A894G missense transition in exon 6 of Pax3 gene that resulted in Asn to Asp substitution at amino acid 269 within the highly-conserved homeodomain (HD) DNA recognition module, which was the first point mutation found in this domain in mice. This N269D mutation impaired the transactivation capacity of Pax3 protein, but exerted no effect on Pax3 protein translation. The characterization of the new mutation expanded our understanding the transactivation and DNA-binding structure of Pax3 protein.
authors.affiliation: Bio-X Center, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Xiao
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.forename: Kuanjun
authors.initials: K
authors.lastname: He
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
authors.forename: Lun
authors.initials: L
authors.lastname: Yang
authors.forename: Lin
authors.initials: L
authors.lastname: He
authors.forename: Gang
authors.initials: G
authors.lastname: Ma
authors.forename: Xizhi
authors.initials: X
authors.lastname: Guo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005038:Ethylnitrosourea / Q000494:pharmacology; D008040:Genetic Linkage; D006367:HeLa Cells; D006801:Humans; D017880:Limb Deformities, Congenital / Q000235:genetics; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D016296:Mutagenesis; D020125:Mutation, Missense; D041681:NIH 3T3 Cells; D009436:Neural Tube Defects / Q000235:genetics; D000072041:PAX3 Transcription Factor; D051761:Paired Box Transcription Factors / Q000737:chemistry / Q000235:genetics*; D016135:Spinal Dysraphism / Q000235:genetics; D015533:Transcriptional Activation / Q000235:genetics
chemical_list: D000072041:PAX3 Transcription Factor; D051761:Paired Box Transcription Factors; C068686:Pax3 protein, mouse; D005038:Ethylnitrosourea