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)

Polysomes producing IgGl(kappa) myeloma protein were specifically selected by an immunoprecipitation method, and immunoglobulin light chain mRNA was purified from the precipitated polysomes. The purified mRNA migrated predominantly as a single band and the molecular weight of this mRNA was calculated to be 410.000 by polyacrylamide gel electrophoresis in 98% formamide. A protein possessing a molecular weight of 25,000, which is the size of the light chain precursor, was synthesized as a major product of translation in a wheat germ cell-free system. DNA complementary to the mRNA (cDNA) was prepared with avian myeloblastosis virus RNA-dependent DNA polymerase. This cDNA had an average size of 8.3S as determined by sedimentation through an alkaline sucrose gradient. Using this cDNA, Crt 1/2 values of template RNA and RNA from various preparations were calculated from the results of molecular hybridization. The relative content of the mRNA increased 4,4-fold during the immunoprecipitation of polysomes.
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PMID:Purification of immunuglobulin light chain messenger RNA by immunoprecipitation from mouse myeloma tumor, MOPC-31C. 40 23

Immunoglobulin heavy chain mRNA was purified from immunoprecipitated polysomes derived from the mouse myeloma tumor, MOPC-31C. The purified mRNA migrated predominantly as a single band upon polyacrylamide gel electrophoresis in 98% formamide and the molecular weight of this mRNA was calculated to be 700,000. This mRNA was as active as the purified light chain mRNA when it was employed as a template in a cell-free protein synthesizing system from wheat germ. The translation product had a molecular weight of 55,000 daltons, and migrated slightly faster than mature heavy chain upon polyacrylamide gel electrophoresis in sodium dodecylsulfate. The protein synthesized by the direction of this mRNA was shown to yield tryptic peptides corresponding to those derived from the mature heavy chain protein except that one missing peptide was replaced by another additional peptide. DNA complementary to the mRNA was synthesized by RNA-dependent DNA polymerase from avian myeloblastosis virus. Hybridization kinetic analysis between the heavy chain mRNA and its complementary DNA indicated that the RNA was essentially homogenous with rabbit globin mRNA as a standard.
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PMID:Purification of immunoglobulin heavy chain messenger RNA by immunoprecipitation from the mouse myeloma tumor, MOPC-31C. 40 24

32P-labeled light chain messenger RNA was prepared from mouse MOPC 21 myeloma cells. The messenger RNA was hybridized to purified repetitive nuclear DNA and both the hybridized (repetitive 32P-RNA) and nonhybridized (nonrepetitive 32P-RNA) fractions were isolated. Only the nonhybridized RNA gave a T1 ribonuclease fingerprint showing oligonucleotides derived from the variable and constant regions of the light chain messenger RNA. In addition, this fingerprint showed oligonucleotides derived from the untranslated regions of the light chain messenger RNA. The nonrepetitive 32P-RNA was shown to rehybridize only with the unique fraction of total nuclear DNA. The rapidly hybridizing part of the unfractionated 32P-RNA preparation, therefore, is not a component of the light chain messenger RNA itself. Complementary DNA was prepared with reverse transcriptase using unlabeled light chain messenger RNA as template, and the transcripts were fractionated into various size classes. Complementary DNA molecules greater than 900 bases in length hybridized with both the initial messenger RNA and with the nonrepetitive 32P-RNA but failed to hybridize with excess purified repetitive 32P-RNA. The rapidly hybridizing component of the messenger RNA fraction, therefore, does not appear to be transcribed by reverse transcriptase. It is concluded that, under the experimental conditions used, the light chain messenger RNA hybridizes exclusively with unique DNA.
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PMID:Demonstration that a mouse immunoglobulin light chain messenger RNA hybridizes exclusively with unique DNA. 80 42

We investigated by molecular hybridization whether T cells contain RNA sequences homologous to RNA which codes for immunoglobulin kappa-chain (k-chain). A radioactive probe of complementary DNA (cDNA) was prepared by transcription of purified k-chain mRNA from mouse myeloma MOPC-41 with reverse transcriptase (RNA-dependent-DNA nucleotidyltransferase) from avian myeloblastosis virus. The cDNA probably corresponded only to the constant region and 3'-terminus of k-chain mRNA. Kappa-chain cDNA was found to hybridize efficiently with RNA from both thymus cells and an established culture of thymoma cells. The thymus and thymoma cells contained 99.8% and 100% theta-positive cells, respectively. Quantitatively the average thymus T cell (thymus derived lymphocyte) contained about one half as much k-chain mRNA as the average spleen B cell ("bursa" dependent lymphocyte), whereas the thymoma cells contained only 1/33 as much. Control hybridizations of k-chain cDNA with myeloma and liver RNA support the conclusion that T cells in the thymus and in the thymoma cell line synthesize k-chain mRNA-like molecules. The thermal stability of hybrids of k-chain cDNA with RNA from spleen, thymus, thymoma, and another k-chain producing myeloma tumor was lower than that with MOPC-41 RNA. This finding may be due to the existence of several slightly different ck genes in the mouse as suggested by various control experiments.
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PMID:Sequences related to immunoglobulin kappa chain messenger RNA in T cells. 82 Oct 55

Intracisternal A particles (IAPs) are retrovirus-like structures consistently observable in a variety of mouse tumor cells such as myeloma and hybridoma and in early embryonic cells derived from rodents but nothing is known of their infectivity. Mouse IAPs contain a gag-like protein, a reverse transcriptase and a polyadenylated RNA molecule (IAP RNA). DNA sequences complementary to IAP RNA (IAP genome) are interspersedly present in rodent such as mice, rats, Chinese hamsters and Syrian hamsters at several hundred to a thousand copies per haploid genome. Molecularly cloned IAP genomes from two species Mus and Syrian hamster were 6 to 8 kb in length with LTRs of about 0.4 kb long. The nucleotide sequence of the Syrian hamster IAP genome, H18, predicted a typical LTR-gag-prt-pol-env-LTR structure, although many stop codons were present in the region corresponding to env. The comparison of the deduced amino acid sequences of the pol region showed IAP (type A), mouse mammary tumor virus (MMTV) (type B), and squirrel monkey retrovirus (SMRV) (type D) genomes to be closely related. By using a DNA fragment encoding the pol region of the Syrian hamster IAP genome, human endogenous retroviruses termed HERV-K, were cloned from a fetal human liver gene library. Typical HERV-K genome was 9.5 kb in length having LTRs of about 1.0 kb. The HERV-K provirus could encode gag (666 codons), prt (334 codons), pol (937 codons), and env (618 codons) genes. HERV-K was shown to be closely related to types A, B and D retroviruses. The HERV-K genomes are present at about 50 copies per haploid human genome. In several human tumor cell lines, the HERV-K genome was expressed as 8.8 kb poly(A)+ RNA which appeared to be a full-size transcript of this genome. In the human breast cancer cell line T47D, stimulation of HERV-K genome expression was observed following female steroids treatment. In a detailed investigation on the organization of HERV-K proviruses in human genome, we found repetitive sequences homologous to the LTR region of the HERV-K genome. They were about 630 bp in length with an A rich tail at 3' end and found to be a SINE type nonviral retroposon. These elements were present at 4,000 to 5,000 copies per haploid human genome.
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PMID:Molecular biology of type A endogenous retrovirus. 171 Jun 82

Although an autocrine growth mechanism through interleukin 6 has been advocated in human myeloma cells, reports of IL-6 production by cells from established myeloma cell lines are rare. In the present study, we examined whether or not a minute amount of interleukin 6 is produced in 4 human myeloma cell lines. IL-6 production was not detected in any of the 4 lines by enzyme immunoassay, bioassay with two interleukin 6-dependent murine hybridoma cell lines and Northern hybridization. However, we detected interleukin 6 mRNA in one (U266) of the 4 lines by the reverse transcriptase-polymerase chain reaction. Nevertheless, the proliferation of all 4 lines was not inhibited by an anti-interleukin 6 antibody. These results suggest that autocrine stimulation by interleukin 6 is not involved in the majority of human myeloma cell lines.
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PMID:Estimation of interleukin 6 production by reverse transcriptase-polymerase chain reaction in four human myeloma cell lines. 172 Apr 89

A novel method using combined chemical and enzymatic reactions to allow the preparation of covalently cross-linked DNA duplexes has been described. The method can be used to specifically link two complementary bases of a DNA duplex containing all four natural bases. The modified nucleotide 9-(2-deoxy-5-O-triphospho-beta-D-ribofuranosyl)-N6,N6-ethano -2,6-diaminopurine (6edDTP) was prepared by total chemical synthesis and was found to be incorporated into DNA duplexes in the place of 2'-deoxyguanosine 5'-O-triphosphate by the Klenow fragment of Escherichia coli DNA polymerase I, T4 and T7 DNA polymerases, avian myeloma virus reverse transcriptase, and rat DNA polymerase beta. Once incorporated, the aziridine of the nucleotide is rapidly opened by the N4 of the cytosine on the complementary strand to give cross-linked DNA, where the modified nucleotide is covalently joined to the complementary base by an ethano linkage. The duplexes produced were found to be recognized as substrates by various DNA polymerases. The Km for the incorporation of the 6edDTP into DNA catalyzed by the Klenow fragment of E. coli DNA polymerase I was found to be 29 microM, and the kcat was found to be 0.014 s-1. The modified nucleoside also served as a substrate for terminal deoxynucleotidyltransferase, where it was added to single-stranded DNA and then hybridized to a complementary strand, after which cross-linking of the two strands occurred within 1 min.
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PMID:A novel combined chemical-enzymatic synthesis of cross-linked DNA using a nucleoside triphosphate analogue. 198 67

Total cellular Poly A+ RNA from TEPC15 myeloma and murine lymphoid tissues was analyzed by denaturing agarose gel electrophoresis and Northern blot hybridization to specific heavy chain constant region cDNAs; mu, gamma 2b and alpha RNA species were identified in each of the tissues and in the IgA producing TEPC15 myeloma. In total Poly A+ RNA from TEPC15 myeloma, alpha-cDNA hybridized predominantly to a 2.3 kb RNA species; 11.5 and 4.1 kb RNA species were evident as well. Successive hybridization of the same RNA to mu- and gamma 2b-specific cDNAs demonstrated the presence of both mu and gamma 2b specific RNA species with electrophoretic mobilities apparently identical to the 11.5 and 2.3 kb RNA species identified by alpha-specific hybridization. These data establish the presence of Poly A+ RNA species containing alpha, mu, and gamma 2b sequences in TEPC15 cells and suggest the transcription of RNA from both CH-containing chromosomes in TEPC15 myeloma (one chromosome in the TEPC15 cell line contains all the CH genes while the other chromosome has deleted all CH genes except alpha). In total Poly A+ RNA from normal mouse tissues (Peyer's patch and spleen) all three cDNA probes hybridized predominantly to an 11.5 kb RNA species. Primer extension experiments demonstrated that alpha cDNA could prime for the synthesis by reverse transcriptase of gamma 2b DNA when Peyer's patch Poly A+ RNA was used as the template. This suggests the existence of a single transcript containing alpha and gamma 2b sequences. Murine lymphoid tissues contained putative mRNAs for mu, gamma 2b and alpha heavy chain proteins, whereas TEPC15 myeloma polysomal Poly A+ RNA contained only alpha mRNA.
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PMID:Identification of the major immunoglobulin heavy chain poly A+ RNA in murine lymphoid tissue. 242 42

We have combined, in a rapid and straightforward manner, the synthesis and subsequent amplification of individual cDNA sequences from microgram quantities of unfractionated total RNA. Taq1 polymerase, a thermostable DNA polymerase, and Moloney murine leukemia virus (MMLV) reverse transcriptase share similar buffer conditions; these reactions can be performed sequentially, in a single tube, without the need for purification or changes of buffer after the synthesis of cDNA. In this way, nonspecific losses of material are minimized and the required number of cells is reduced. Cell numbers, particularly from human tissues, can be limiting; the requirement for only small amounts of unfractionated RNA makes possible the isolation and characterization of cDNAs from biological materials available in limited quantities. As a demonstration system, we report the rapid synthesis and amplification of cDNA sequences corresponding to the first exon of human immunoglobulin E (IgE). MMLV reverse transcriptase is used with specific (i.e., IgE) or generic (i.e., oligo-[dT(12-18)]) oligomers to prime first strand cDNA synthesis from unfractionated RNA isolated from a human myeloma line, U-266. The necessary primers, deoxynucleotides and Taq1 polymerase, required for second strand cDNA synthesis and the subsequent logarithmic amplification process, are then added to the reaction mixture. This technique provides a useful means of characterizing expressed and processed gene transcripts.
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PMID:Rapid amplification of complementary DNA from small amounts of unfractionated RNA. 247 58

Bovine leukemia provirus is reported to be integrated in the DNA of different infected mammalian cells. We observed morphological transformation in BLV infected sheep fetal spleen, kidney, thymus and sternal cultures. The presence of BLV specific sequences in their genome was established after digestion with the restriction endonuclease EcoRI and hybridization with a BLV specific probe. Human myeloma ARH77 and myeloid K562 cells infected with BLV were virus productive as detected by a reverse transcriptase assay. The presence of proviral sequences was confirmed after Southern blotting analysis. Restriction digestion by SacI enzyme yielded a complete 8.9 kb BLV provirus in infected ARH77 cells and a smaller 7.5 kb BLV fragment in infected K562 cells.
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PMID:Bovine leukemia provirus in the DNA of different infected host cells. 302 95


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