Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An 8.0-kb EcoRI fragment of the human immunoglobulin (Ig) lambda light chain locus carrying the Ke-Oz- and Ke-Oz+ constant region genes and flanking sequences was studied for the presence of a transcriptional enhancer. Two types of assays were used. In the first, we measured the ability of recombinant plasmids carrying the 8.0-kb Ig fragment covalently linked to the aminoglycoside phosphotransferase (aph) gene to transform mouse myeloma or mouse fibroblast cells to geneticin resistance. In the second, we used RNA spot and Northern blot hybridization analyses to determine the relative levels of aph specific RNA transiently expressed after DNA transfection. In fibroblast cells, the transformation frequencies were independent of the presence of the Ig fragment in the vector and there was no difference in the level of transient expression of the aph gene. In myeloma cells, the Ig fragment enhanced at least 10-fold both the number of transformants and the level of aph gene expression over that obtained with vector alone. These results indicate the presence of a tissue-specific transcriptional enhancer in the 8.0-kb EcoRI fragment of the human Ig C lambda locus.
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PMID:A tissue-specific transcription enhancer element in the human immunoglobulin lambda light chain locus. 620 48

The human light chain JC lambda locus is comprised of seven distinct segments, designated JC lambda 1, JC lambda 2, JC lambda 3, JC lambda 4, JC lambda 5, JC lambda 6, and JC lambda 7. Whereas three of these seven represent pseudogenes (psi Clambda 4, psi C lambda 5, and psi C lambda 6), the JC lambda 1, JC lambda 2, and JC lambda 3 complexes are functional, as demonstrated by the finding of their protein products through sequence analyses of lambda-type Bence Jones proteins and light chains derived from monoclonal Igs. Although the JC lambda 7 segment also appears functional, as evidenced through analysis of lymphocyte-derived mRNA, heretofore no monoclonal JC lambda 7-containing lambda-chains have been identified. Serologically, two distinct isotypic markers, Mcg and Oz, are associated, respectively, with JC lambda 1 and JC lambda 3 proteins, in contrast to JC lambda2 components, which do not express these determinants and represent a third isotype. Although another serologic marker, Ke (Kern), considered a fourth isotype, has been assigned to the JC lambda 7 complex, this relationship has been questioned. We now report the primary structural features of a lambda-type Bence Jones protein that include the four distinctive residues encoded by the JC lambda 7 gene segment. This protein, obtained from a patient with multiple myeloma and designated MCP, represents the first example of such a molecule and provides definitive evidence that the JC lambda 7 gene complex is functional. Additionally, comparison of the C lambda sequences of Mcg-/Oz- Bence Jones proteins MCP and KERN supports the contention that the Ke-associated one-residue amino acid variation at position 152 reflects a C lambda A2 polymorphism and that yet another isotypic marker, provisionally designated Mcp, is encoded by the JC lambda 7 gene segment. Thus, we posit that there are four human JC lambda isotypes, Mcg, Ke-Oz-/Ke+Oz-, Ke-Oz+, and Mcp, that represent, respectively, products of the JC lambda 1, JC lambda 2, JC lambda 3, and JC lambda 7 gene complexes.
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PMID:Characterization of a light chain product of the human JC lambda 7 gene complex. 890 24