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F H Ruddle

Publications and source records attributed to F H Ruddle.

At least 163 records · Page 9Linked to original sources

Molecular cloning and structural analysis of murine thymidine kinase genomic and cDNA sequences.

Two functional cytosolic thymidine kinase (tk) cDNA clones were isolated from a mouse L-cell library. An RNA blot analysis indicated that one of these clones contains a nearly full-length tk sequence and that LTK- cells contain little or no TK message. The nucleotide sequences of both clones were determined, and the functional mouse tk cDNA contains 1,156 base pairs. An analysis of the sequence implied that there is an untranslated 32-nucleotide region at the 5' end of the mRNA, followed by an open reading frame of 699 nucleotides. The 3' untranslated region is 422 nucleotides long. Thus, the gene codes for a protein containing 233 amino acids, with a molecular weight of 25,873. A comparison of the coding sequences of the mouse tk cDNA with the human and chicken tk genes revealed about 86 and 70% homology, respectively. We also isolated the tk gene from a mouse C57BL/10J cosmid library. The structural organization was determined by restriction mapping, Southern blotting, and heteroduplex analysis of the cloned sequences, in combination with a mouse tk cDNA. The tk gene spans approximately 11 kilobases and contains at least five introns. Southern blot analysis revealed that this gene is deleted in mouse LTK- cells, consistent with the inability of these cells to synthesize TK message. This analysis also showed that tk-related sequences are present in the genomes of several mouse strains, as well as in LTK- cells. These segments may represent pseudogenes.

Amino Acid Sequence↗

Human metallothionein-II processed gene is located in region p11----q21 of chromosome 4.

Metallothionein (MT) genes comprise a multigene family encoding low-molecular-weight, heavy-metal-binding proteins. We have mapped a human MT-II processed gene to chromosome 4, using Southern blotting in combination with a human X mouse hybrid clone panel containing defined subsets of human chromosomes. We have further localized this gene to region p11----q21, using in situ hybridization.

Animals↗

Regional localization of the human transferrin receptor gene to 3q26.2----qter.

Transport of iron across the cell membrane is mediated by the iron-binding serum protein, transferrin, and its cell-surface receptor. Transferrin receptor is required for cell proliferation and may play a functional role in the pathogenesis of iron-storage disorders and some neoplasias. To better understand the possible involvement of transferrin receptor in such disorders, we have determined the chromosomal locus of the receptor gene by in situ hybridization. The human transferrin receptor gene was thus mapped to 3q26.2----qter, a region of chromosome 3 that appears to be involved in metal transport and that is subject to nonrandom structural rearrangements associated with neoplasia.

Chromosome Mapping↗

Chromosomal location of human T-cell receptor gene Ti beta.

A complementary DNA probe corresponding to the beta-chain gene of Ti, the human T lymphocyte receptor, has been molecularly cloned. The chromosomal origin of the Ti beta gene was determined with the complementary DNA by screening a series of 12 cell hybrid (mouse X human) DNA's containing overlapping subsets of human chromosomes. DNA hybridization (Southern) experiments showed that the human Ti beta gene resides on chromosome 7 and is thus not linked to the immunoglobulin loci or to the major histocompatibility locus in humans.

Animals↗

Murine T cell receptor beta chain is encoded on chromosome 6.

Southern blot analysis of somatic cell hybrid lines indicates that the beta chain of the T cell receptor for antigen maps to chromosome 6 of the mouse. An experiment testing hybridization of the constant region of this gene to DNA from a hybrid cell line containing a translocation of chromosome 6 supports the localization of this gene to the proximal (centromeric) one-third of chromosome 6, in the same general region as the immunoglobulin kappa chain locus. This may be another indication of the shared evolutionary origins of the genes encoding both T and B cell antigen recognition.

Animals↗

Molecular cloning and chromosome assignment of murine N-ras.

The murine N-ras gene was cloned by screening an EMBL-3 recombinant phage library with a human N-ras specific probe. Hybridization of two separate unique sequence N-ras probes, isolated from the 5' and 3' flanking sequences of the murine gene, to a mouse-Chinese hamster hybrid mapping panel assigns the N-ras locus to mouse chromosome three.

Animals↗

Glutathione S-transferase Ya subunit is coded by a multigene family located on a single mouse chromosome.

A cloned DNA probe of Ya, the major glutathione S-transferase subunit in rat liver, was used to study the organization of Ya genes in the mouse genome. Southern blot analysis of mouse genomic DNA indicates that the Ya subunit is encoded by a multigene family. The chromosomal distribution of Ya genes was determined by analysis of DNA from a panel of mouse-Chinese hamster somatic cell hybrids. All detectable Ya genes were found to be located on chromosome 9. At least some of the Ya-specific DNA sequences are clustered since, by screening a mouse genomic library, two recombinant phages, each containing two different Ya DNA sequences in the same insert, have been isolated. The finding that Ya is encoded by a cluster of different genes raises the question of the specificity of the different Ya DNA sequences.

Animals↗

Genetic and biochemical characterization of human lymphocyte cell surface antigens. The A-1A5 and A-3A4 determinants.

The genes that code for the human lymphocyte cell surface determinants defined by monoclonal antibodies A- 1A5 and A- 3A4 have been genetically mapped. All human chromosomes, except Y, were included in a series of human less than mouse lymphocyte hybrid populations that retained expression of lymphocyte-specific surface markers. Expression of the A- 1A5 and A- 3A4 antigens was quantitated by indirect immunofluorescence and fluorescence-activated cell sorter (FACS) analysis. Hybrid populations heterogeneous for antigen expression were sorted to yield antigenically homogeneous subpopulations. Isozyme analysis indicated concordant segregation of the A- 1A5 determinant with chromosome 10, and the A- 3A4 determinant with chromosome 4. In contrast to the unhybridized human parent cell line (MOLT-4), from which A- 1A5 immunoprecipitated two proteins (160,000 and 125,000 Mr), A- 1A5 only immunoprecipitated a single band (125,000 Mr) from an A- 1A5 -expressing human less than mouse hybrid. The genetic disassociation of these two proteins from the A- 1A5 -reactive complex suggests that the appearance of the 160,000 Mr protein requires a gene locus that is unlinked to the locus for the 125,000 Mr protein on chromosome 10. A third component of the A- 1A5 -reactive protein complex (210,000 Mr), which is recognized by the monoclonal antibody TS2/7, was not expressed on the parent MOLT-4 cells, but was weakly expressed on MOLT-4 less than mouse BW5147 hybrids. This allowed preliminary mapping of that determinant to either chromosome 10 or 15. The A- 3A4 antigen (approximately 45,000 Mr) is a novel cell surface structure expressed on all hematopoietic cell lines tested, and represents the first cell surface marker mapped to chromosome 4.

Animals↗

Interferon-beta-related DNA is dispersed in the human genome.

Interferon-beta 1 (IFN-beta 1) complementary DNA was used as a hybridization probe to isolate human genomic DNA clones lambda B3 and lambda B4 from a human genomic DNA library. Blot-hybridization procedures and partial nucleotide sequencing revealed that lambda B3 is related to IFN-beta 1 (and more distantly to IFN-alpha 1). Analyses of DNA obtained from a panel of human-rodent somatic cell hybrids that were probed with DNA derived from lambda B3 showed that lambda B3 is on human chromosome 2. Similar experiments indicated that lambda B4 is not on human chromosomes 2, 5, or 9. The finding that DNA related to the IFN-beta 1 gene (and IFN-alpha 1 gene) is dispersed in the human genome raises new questions about the origins of the interferon genes.

Animals↗

The use of cell surface antigens to characterize and select for fragments of human chromosomes retained by interspecies hybrids.

We have used a mouse cell transformant generated by human chromosome-mediated gene transfer (CMGT) to explore the use of cell surface antigens in the identification of fragments of human chromosomes retained by somatic cell hybrids. The transformed line, 21-30b, contained an intact rear-ranged human chromosome, and could be shown by isozyme analysis to contain genetic material from chromosomes 9 and X. By using the transformant as an immunogen in mice, it was also possible to produce antiserum to human-specific surface antigens. Using genetically characterized human X rodent hybrid lines, the genes controlling expression of these antigens could be localized to 11per----11p13, segregating concordantly with surface antigen S3. These conclusions were possible despite the fact that the presence of chromosome 11 in the transformant was not detectable by the presence of chromosome specific isozyme LDH-A or surface antigens W6/34 and 4F2. Finally, the fluorescence-activated cell sorter (FACS) was used to fractionate the transformant cells into antigen positive and negative subpopulations. This resulted in the isolation and characterization of four additional chromosome rearrangements involving interspecies chromosome translocations. This work demonstrates the value of chromosome-specific surface antigens and the FACS in the evaluation of human chromosome fragments retained by interspecies hybrids.

Animals↗

Assignment of low-molecular-weight human (2', 5')A synthetase to chromosome 11.

Human low-molecular-weight (2', 5')A synthetase is induced in certain human X mouse somatic hybrid cell lines when these cells are treated with mouse interferon. We have assigned the gene coding for this interferon-inducible antiviral enzyme to human chromosome 11 by somatic cell genetic techniques (1). Fluorescence-activated cell sorting for cells expressing or lacking 4F2 antigen in two independently derived, chromosome 11-containing hybrid cell lines separated the cells into subpopulations of cells that had retained or segregated chromosome 11, respectively (2). We used these subpopulations to confirm our gene assignment by demonstrating that retention of chromosome 11 was required for expression of human (2', 5')A synthetase.

2',5'-Oligoadenylate Synthetase↗

Somatic cell hybrid mapping panels.

The recent advances in human gene mapping have been largely due to the development of interspecies cell hybrids containing human chromosomes and their fragments. The importance of characterized panels of these hybrid lines has grown exponentially with the application of recombinant DNA technologies to human genetics. In this article, we discuss current strategies employed in the construction of somatic cell hybrid mapping panels.

Animals↗

Antibodies to chromosome 21 coded cell surface components block binding of human alpha interferon but not gamma interferon to human cells.

Antisera raised against a human X mouse hybrid cell line containing human chromosome 21 as its only human chromosome, block induction of an antiviral state by human alpha interferon (IFN-alpha), block induction of (2'-5')oligoisoadenylate synthetase [2'-5')A synthetase), and block binding of 125I-labeled and 35S-labeled recombinant, human IFN-alpha A, but not 125I-labeled IFN-gamma, to cell surface receptors. The data presented clearly demonstrate that the cell surface receptors for IFN-alpha and IFN-gamma are different, and provide independent evidence of the role of a chromosome 21 coded cell surface molecule in the pathway to the generation of the antiviral state.

2',5'-Oligoadenylate Synthetase↗

The human transferrin receptor gene: genomic organization, and the complete primary structure of the receptor deduced from a cDNA sequence.

Heteroduplex analysis shows that the transferrin receptor gene contains at least 19 distinct coding sequences distributed over 31 kb of genomic DNA. The nucleotide sequence of these coding regions has been determined from a cDNA clone. The sequence contains a single complete open reading frame of 2280 bases which specifies a 760 residue polypeptide with a molecular weight of 85K daltons. The deduced amino acid sequence of the receptor shows that it does not contain an N-terminal hydrophobic signal peptide. We have found a single region of sufficient length and hydrophobicity to span the membrane, located 61 amino acids from the N-terminus. This leads to the prediction that the receptor is oriented in the membrane with a cytoplasmic N-terminus and an extracellular C-terminus. The receptor has no significant homology with transferrin, or with any receptor for which a sequence is available.

Amino Acid Sequence↗

Molecular cloning and chromosome mapping of a mouse DNA sequence homologous to homeotic genes of Drosophila.

Some of the homeotic genes of Drosophila, involved in the control of segmental development, form a diverged multigene family. A conserved DNA sequence common to these genes has been used to isolate a clone (Mo-10) from the mouse genome which contains a sequence coding for a protein domain that is homologous to the domain conserved in the Drosophila homeotic genes. By structural analogy, this sequence may be involved in the control of metameric pattern formation in the mouse. Mo-10 has been mapped to the proximal portion of mouse chromosome 6, and its position in relationship to genes known to influence mouse morphogenesis is discussed.

Amino Acid Sequence↗