该基因编码第三个被发现的果蝇黑腹型膜蛋白缺口的人类同源物。在果蝇中，notch与细胞结合配体（delta，serate）的相互作用建立了一个细胞间信号通路，在神经发育中起着关键作用。Notch配体的同系物也已在人类中鉴定出来，但这些配体与人类Notch同系物之间的精确相互作用仍有待确定。Notch3突变被认为是伴有皮质下梗死和白质脑病（CADASIL）的大脑常染色体显性动脉病变的根本原因。
This gene encodes the third discovered human homologue of the Drosophilia melanogaster type I membrane protein notch. In Drosophilia, notch interaction with its cell-bound ligands (delta, serrate) establishes an intercellular signalling pathway that plays a key role in neural development. Homologues of the notch-ligands have also been identified in human, but precise interactions between these ligands and the human notch homologues remains to be determined. Mutations in NOTCH3 have been identified as the underlying cause of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).