Cloning and sequencing of a rearranged Vλ gene from a burkitt's tymphoma cell line expressing kappa light chains

Abstract

We have cloned and sequenced a rearranged Vλ gene from a Burkitt's lymphoma cell line PA682(PB). This cell line has two rearranged K loci and has been shown to be expressing K light chains (1). This Vλ gene has been identified as a member of the Vλ subgroup III gene family based on the homology of the predicted amino acid sequence of PAVλ with the reported sequences of the Vλ protein DEL of subgroup III. Nine cross-hybridizing bands have been detected on Southern blots and the chromosomal orientation of the Vλ subgroup III gene family has been determined in relation to the Vλ subgroup I gene family. Although the PAVλ rearrangement has occurred via a legitimate V-J joining and a normal size transcript is detected on Northern blots, the nucleotide sequence reveals a high level of mutations resulting in multiple termination signals within the V gene coding sequence and only a truncated Vλ protein can be translated. This confirms previous observations that although multiple light chain genes may be transcribed, only one functional light chain protein can be synthesized. © 1985 IRL Press Limited.