Correct transcription of an immunoglobulin kappa gene requires an upstream fragment containing conserved sequence elements.

Transcription of the immunoglobulin kappa light-chain genes depends on the presence of a TATA box upstream of the leader gene segment and is regulated by an enhancer sequence in the large intron. In studying a rearranged mouse kappa light-chain gene we have now found that sequences between--90 and--160 base pairs (bp) upstream of the coding region are essential for correct transcription in gene transfer experiments. This region contains the deca- and pentadecanucleotide sequences TNATTTGCAT and TGCAGCCTGTGNCCAG, which we call dc and pd, respectively. Sequences related to dc and pd were found upstream of all human and mouse kappa-chain variable region (Vk) genes, upstream of lambda-chain variable region (V lambda) genes, and within the mouse heavy-chain enhancer. An inverted and complementary form of the dc element (ATGCAAATNA, called cd) occurs upstream of all heavy-chain variable region (VH) genes. The newly defined sequences may be involved in the control of immunoglobulin gene transcription.