PAX3

Paired box 3
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 3CMY
Identifiers
Symbols	PAX3 ; CDHS; HUP2; WS1; WS3
External IDs	OMIM: 606597 MGI: 97487 HomoloGene: 22494 GeneCards: PAX3 Gene
Gene ontology Molecular function • chromatin binding • sequence-specific DNA binding transcription factor activity • RNA polymerase II distal enhancer sequence-specific DNA binding transcription factor activity • protein binding • sequence-specific DNA binding • HMG box domain binding Cellular component • nucleoplasm Biological process • negative regulation of transcription from RNA polymerase II promoter • neural crest cell migration • neural tube closure • chromatin organization • transcription from RNA polymerase II promoter • apoptotic process • heart development • sensory perception of sound • cell proliferation • positive regulation of cell proliferation • organ morphogenesis • regulation of somitogenesis • spinal cord association neuron differentiation • positive regulation of transcription, DNA-templated • positive regulation of transcription from RNA polymerase II promoter • developmental pigmentation • neuron fate commitment • skeletal muscle organ development • mammary gland specification Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	5077	18505
Ensembl	ENSG00000135903	ENSMUSG00000004872
UniProt	P23760	P24610
RefSeq (mRNA)	NM_000438	NM_001159520
RefSeq (protein)	NP_000429	NP_001152992
Location (UCSC)	Chr 2: 222.2 – 222.3 Mb	Chr 1: 78.1 – 78.2 Mb
PubMed search	[1]	[2]

PAX3 is a gene that belongs to the paired box (PAX) family of transcription factors. This gene was formerly known as splotch. PAX3 has been identified with ear, eye and facial development. Mutations in it can cause Waardenburg syndrome types 1 and 3 . It is expressed in early embryonic phases in dermatomyotome of paraxial mesoderm which it helps to demarcate. In that way PAX3 contributes to early striated muscle development since all myoblasts are derived from dermatomyotome of paraxial mesoderm.

Alternative splicing results in transcripts encoding isoforms with different C-termini.

Role in rhabdomyosarcoma

A PAX3/FKHR fusion gene is often associated with the alveolar type of rhabdomyosarcoma, a kind of cancer arisen from striated muscle cells. Translocation between chromosomes 2 & 13 produce fusion protein PAX3/FKHR which serves as a tumor marker in this type of RMS.Also in ARMS expressing PAX3/FKHR increased risk of metastasis to bone marrow and hence increased rate of failure and death were seen.

Interactions

PAX3 has been shown to interact with MEOX1, MEOX2 and SOX10 as well as phosphatidylcholine transfer protein (PCTP). PAX3 has an important relationship with c-met in myogenesis; if PAX3 is mutated, c-met expression may be inhibited or prevented altogether resulting in a lack of lateral migration.

External links

• GeneReviews/NCBI/NIH/UW entry on Waardenburg Syndrome Type I
• PAX3 protein, human at the US National Library of Medicine Medical Subject Headings (MeSH)