Family with sequence similarity 131 member B (FAM131B)

Family with sequence similarity 131 member B (FAM131B) is an intracellular protein encoded by the FAM131B gene. It belongs to the FAM131 family and is primarily localized in the cytosol and nucleoplasm. The principal biological and clinical relevance of FAM131B lies in its participation as a fusion partner with BRAF (FAM131B-BRAF fusion), where it drives constitutive activation of the MAPK pathway, contributing to oncogenesis in pilocytic astrocytoma[1][3][4][5][6]. FAM131B is also associated with myotonia congenita, though its molecular function remains largely uncharacterized. There are no approved drugs targeting FAM131B directly, but its fusion gene is a relevant biomarker and therapeutic context in certain cancers.

Other names

FAM131Bprotein FAM131BKIAA0773FAM131BphFAM131BE5RI17E5RJ60

Null for FAM131B directly; for FAM131B-BRAF fusion, constitutive activation of the MAPK pathway (via MEK phosphorylation) underlies its oncogenic mechanism