THE PROTEINS ENCODED BY THE VPREB AND LAMBDA-5 PRE-B-CELL SPECIFIC GENES CAN ASSOCIATE WITH EACH OTHER AND WITH MU HEAVY-CHAIN

The murine pre-B cell-specific genes VpreB and λ5, as well as the murine gene for µ heavy chain, were introduced into Ltk - fibroblast cells which normally do not express these genes. Stable transfectants carrying these genes produced the corresponding proteins of 15.5, 21.5, and 75 kD. They secreted the three proteins as a triple complex that could be immunoprecipitated by ti heavy chain-specific antibodies, consisting of one VpreB, one λ5, and one µ heavy chain. The µ heavy chain and λ5 were disulfide-bonded with each other, while the VpreB protein was noncovalently associated. These experiments proved that the VpreB, λ5 and µ H chain proteins can form a heavy/light chain-like heterocomplex. © 1990, Rockefeller University Press., All rights reserved.