PAX3

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

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

Role in rhabdomyosarcoma
A PAX3/FKHR is_associated_with::fusion gene is often associated with the alveolar type of is_associated_with::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 is_associated_with::MEOX1, is_associated_with::MEOX2 and is_associated_with::SOX10 as well as is_associated_with::phosphatidylcholine transfer protein (PCTP). PAX3 has an important relationship with c-met in is_associated_with::myogenesis; if PAX3 is mutated, c-met expression may be inhibited or prevented altogether resulting in a lack of lateral migration.