Karyopherin Alpha 1 (KPNa1)

Recombination activating proteins RAG1 and RAG2 regulate and mediate V(D)J recombination, the process by which genes for immunoglobulins and T-cell receptors are generated. Several other ubiquitously expressed proteins are thought to be recruited in the recombination process. Among these are the genes affected in severe combined immune deficiency and genes involved in ds-DNA break repair. KPNa1 interacts with RAG1 and may play a role in V(D)J recombination. The authors obtained human and mouse cDNA sequences which are 98% identical as proteins. When RAG1 and human SRP1 were cotransfected into 293T cells a stable complex of the 2 was observed. The authors speculated that because SRP1 appears to be bound to the nuclear envelope, the interaction with RAG1 may serve to localize that protein to the envelope as well.