Deletion of human JK segments by site-specific recombination recognizing the conserved nonamer and heptamer sequences

摘要

Mapping and partial sequencing of the productive K chain genomic DNA of FK-001 demonstrated a 1.8-kb deletion including the J_K2, J_K3, J_K4, and J_K5 segments. This deletion occurred between the heptamer recombination signal sequence of the J_K2 segment and the heptamer-like sequence located 1.8 kb downstream of the J_K2 segment. The recombination reaction kept the reciprocally joined signal sequences on the chromosome and deleted the intervening DNA segment. The cloned FK-001 K chain gene was expressed efficiently in mouse myeloma cells, demonstrating that the 1.8-kb deleted region conferred no functions for gene expression.