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R W Elliott

Publications and source records attributed to R W Elliott.

At least 19 recordsLinked to original sources

Deletion mapping of the mouse ornithine decarboxylase-related locus Odc-rs8 within Igh-V.

The Odc-rs8 locus belongs to a family of mouse DNA sequences related to the gene encoding ornithine decarboxylase (ODC). Odc-rs8 was mapped by recombinant inbred (RI) strain analysis to the region of Chromosome (Chr) 12 occupied by the variable region genes of the immunoglobulin heavy chain (Igh) complex. In the present study, alleles at Odc-rs8 were shown to cosegregate with those for Igh variable region (Igh-V or VH) genes among 37 inbred mouse strains that had been characterized previously for their haplotypes at Igh. For a more precise definition of the location of Odc-rs8 relative to Igh-V, DNAs from 17 Abelson murine leukemia virus (A-MuLV)-transformed pre-B cell lines cultured from mice heterozygous at Igh and Odc-rs8 were analyzed for the presence of DNA restriction fragments (RFs) derived from each parental Odc-rs8 allele. These cell lines, each of which has rearranged one or both Igh genes, previously were employed in mapping members of nine VH gene families by deletion analysis (Brodeur et al. 1988). Comparing the deletion profiles of the cell lines for Odc-rs8 with those for the VH gene families has located Odc-rs8b within the VHJ558/VH3609 gene cluster and Odc-rs8c either within or upstream of the 5'-most 9% of VHJ558, identifying Odc-rs8 as a potentially useful marker for the 5' end of the Igh complex.

Alleles

Mapping of the mouse ornithine decarboxylase-related sequence family.

A family of DNA sequences homologous to the mRNA encoding ornithine decarboxylase (ODC) and comprising approximately 12 members in the mouse genome has been analyzed genetically. The inheritance of variant DNA restriction fragments detected by ODC cDNA probes on Southern blots of DNA from inbred strain mice was determined in six sets of recombinant inbred (RI) mouse strains. The distributions of these variations among the RI strains were then compared with the RI strain distribution patterns (SDPs) of previously mapped loci. This allowed the identification of nine independent ODC-related loci, of which eight could be localized to specific regions of the mouse genome: Odc-rs1 near Lamb2 on Chromosome (Chr) 1; Odc-rs2 near Psp on Chr 2; Odc-rs5, a complex locus comprising at least 5-7 copies of the ODC sequence, associated with Igk on Chr 6; Odc-rs6 between Abpa and Tam-1 on proximal Chr 7; Odc-rs7 near Hbb on distal Chr 7; Odc-rs12 near Agt and Emv-2 on distal Chr 8; Odc-rs8 associated with the Igh complex on Chr 12; and Odc-rs9 near Otf-3f on Chr 14. The ODC-related sequence family thus comprises a set of genomically dispersed "marker" loci, and alleles for several of these loci can be analyzed simultaneously in DNA from mice or cell lines. DNA from mice of 70 inbred strains has been characterized for alleles at all nine Odc-rs loci.

Alleles

Genetic mapping of two DNA markers, D16Ros1 and D16Ros2, flanking the mutation site in the chakragati mouse, a transgenic insertional mutant.

We present here the genetic mapping of two novel loci, D16Ros1 and D16Ros2, to mouse Chromosome (Chr) 16. The probes for these loci were genomic fragments isolated from the chakragati mouse, a behavioral mutant resulting from insertional mutagenesis during the course of making transgenic mice. D16Ros1 and D16Ros2 were first mapped by recombinant inbred (RI) strain analysis and subsequently by the analysis of 145 progeny of two interspecific backcrosses between Mus domesticus and Mus spretus. These progeny had been typed for the centromere and this allowed mapping of D16Ros1 and D16Ros2 relative to the centromere. The other markers included in this study were Prm-1, Gap43 and Sod-1. The genetic map generated spanned 47.5 cM from the centromere to Sod-1, the most distal marker mapped here. The linkage data presented here should prove useful in mapping other loci relative to the centromere of Chr 16.

Animals

Fine-structure mapping of the complex locus Odc-rs5 relative to Igk and distal loci.

Odc-rs5 was previously identified as a complex locus closely linked to the Igk complex on mouse Chromosome (Chr) 6 and comprising at least five copies of a sequence related to the mRNA encoding ornithine decarboxylase (ODC) in the genomes of mice of some inbred strains and at least seven copies in others (Richards-Smith and Elliott, Mammalian Genome 2: 215, 1992). In the present study, Odc-rs5 was shown to be composed of at least seven copies of the ODC sequence in both the Odc-rs5a and Odc-rs5b haplotypes. Based upon the distribution of DNA restriction fragments (RFs) that had previously been associated with Odc-rs5a or Odc-rs5b among 42 mice of inbred laboratory strains having various haplotypes at Igk and in mice of two congenic strains [B6.PL-Ly-2a, Ly-3a(75NS)/Cy and B6.PL-Ly-2a,Ly-3a(85NS)/Cy] and a backcross-derived stock (NAK) known to be recombinant within Igk, a fine structure map of Odc-rs5 was deduced relative to Igk and more distal loci. Odc-rs5-derived RFs were located to three distinct regions within and/or distal to Igk and to a fourth site between (Ly-3, Ly-2) and Raf-1. Additionally, DNAs from 19 mice of inbred strains and random-bred stocks derived from wild progenitors trapped at various locations were analyzed and found to exhibit an unexpected variety of combinations of RFs associated with the two Odc-rs5 haplotypes most frequently observed among inbred laboratory strains of mice.

Animals

DNA variants with telomere probe enable genetic mapping of ends of mouse chromosomes.

Dde I-digested DNA fragments from 11 inbred mouse strains were separated by electrophoresis, blotted and probed with a labeled oligomer, TELO, containing five repeats of the consensus mammalian telomere sequence, TTAGGG. Each strain produced a unique set of hybridizing fragments. Segregation analysis of TELO-hybridizing fragments from the BXD RI strains indicated that each fragment segregated as expected for a single gene. One fragment from strain DBA/2J was genetically linked to locus Xmv-9, previously mapped near the distal end of the map of chromosome (Chr) 4 and three fragments to Cck, near the distal end of Chr 9, suggesting that these fragments are telomeric and represent the ends of the chromosome maps. Confirmation of these map positions was obtained from a backcross. Fragments associated with the short arm of the Y Chr were found in DNA from strains C57BL/6J and DBA/2J. TELO-hybridizing fragments from DBA/2J were digested by the exonuclease Bal 31, under conditions in which fragments hybridizing to a cDNA probe for the metallothionein locus, located at the middle of mouse Chr 8, remained intact. Thus both biochemical and genetic tests indicate that several TELO-hybridizing fragments from Dde I-digested DNA are at the ends of chromosomes and probably derive from mouse telomeres. Using this approach should allow the mapping of genes relative to the ends of other mouse chromosomes.

Animals

Characterization of a murine cDNA encoding a member of the carboxylesterase multigene family.

We have characterized a mRNA sequence containing the entire coding region of a mouse carboxylesterase (EC 3.1.1.1). pEs-N, an 1840-bp composite of five overlapping cDNA clones, contains an open reading frame of 554 amino acids that display a high degree of similarity with rat and rabbit carboxylesterases. Genetic mapping studies place this carboxylesterase in cluster 1 of the esterase region on chromosome 8. Results of blot hybridization analysis of genomic DNA probed with a pEs-N cDNA under both low and high stringency conditions suggest membership in a carboxylesterase multigene family, as would be expected for a nonspecific carboxylesterase. A message size of 1850-1900 nucleotides was revealed by RNA blot hybridization analysis. S1 nuclease protection analyses with a probe representing a segment of pEs-N detected message in liver, kidney, and lung, but not in spleen, brain, testes, and submandibular gland, with higher levels in female than in male kidney. Additional S1 nuclease-protected mRNA species were found, suggesting the expression of distinct members of a multigene family. In vitro translation of a full-size transcript of pEs-N resulted in a product of 51.5 kDa. Upon the addition of microsomes, this product was processed into a protein of 60.4 kDa, which is within the size range of monomeric units of mouse carboxylesterases.

Amino Acid Sequence

Localization of the gene for plasma retinol binding protein to the distal half of mouse chromosome 19.

A DNA polymorphism for the mouse retinol binding protein has been identified using the enzyme BamHI and a rat partial cDNA probe. Analysis of the polymorphism in DNA from 64 inbred mouse strains demonstrated the presence of a single gene with two alleles, Rbp-4b and Rbp-4d. Comparison of the segregation patterns of these alleles in three sets of recombinant inbred strains with allele segregation patterns of previously characterized loci shows that the Rbp-4 locus is closely linked to the locus for phenobarbital-inducible cytochrome P450-2c (Cyp-2c) that has been shown by in situ hybridization to lie on chromosome 19, bands D1-D2. The Rbp-4 locus is just proximal to Cyp-2c at the distal end of chromosome 19.

Alleles

Localization of the growth hormone gene to the distal half of mouse chromosome 11.

A DNA fragment size variant for the growth hormone gene, Gh, has been identified among inbred strains of mice. The inbred strains SM/J and CAST/Ei carry the less frequent allele Ghb and 11 other strains carry the Gha allele. Segregation analysis of data from two crosses involving SM/J and NZB/BINJ and a cross involving BALB/cJ and CAST/Ei confirmed the assignment of Gh to mouse chromosome 11 and placed the locus 2.6 +/- 1.8 map units distal to Erba (avian erythroblastosis oncogene A), a position consistent with the assignment of the Gh locus to the q22-q24 region of chromosome 17 on the human map. Segregation analysis also refined the location of Sparc (secreted acidic cysteine-rich glycoprotein) on mouse chromosome 11 to a position 16.7 +/- 4.2 map units proximal to Evi-2 (ecotropic viral integration site 2).

Alleles

Characterization of the cDNA coding for mouse plasminogen and localization of the gene to mouse chromosome 17.

A full-length cDNA coding for mouse plasminogen has been isolated and characterized. The cDNA is 2720 bp in length (excluding the poly(A) tail) and contains a 24-bp 5' noncoding region, an open reading frame of 2436 bp, and a 3' noncoding region of 257 bp. The open reading frame codes for 812 amino acids and includes a signal peptide that is likely 19 amino acids in length and the mature protein of 793 amino acids. The calculated Mr of mouse plasminogen is 88,706 excluding carbohydrate. There are two potential N-linked carbohydrate addition sites; one of which is glycosylated in human, bovine, and porcine plasminogens. Mouse plasminogen was found to contain two additional amino acids compared to the human protein. In addition, mouse and human plasminogens were found to be 79 and 76% identical at the protein and DNA levels, respectively. Analysis of the segregation of two allelic forms, Plgb and Plgd, of plasminogen DNA in three sets of recombinant inbred strains has allowed the localization of the mouse plasminogen gene to the proximal end of mouse chromosome 17 within the t complex and close to the locus D17Rp17. The Plg gene is deleted in the semidominant deletion mutant, hair-pintail (Thp).

Alleles

Localization of the rhodopsin gene to the distal half of mouse chromosome 6.

We have assigned the mouse rhodopsin gene, Rho, to chromosome 6 using DNA from a set of mouse-hamster somatic hybrid cell lines and a partial cDNA clone for mouse opsin. This assignment rules out the direct involvement of the rhodopsin gene in the known mouse mutations that produce retinal degeneration, including retinal degeneration slow (rds, chromosome 17), retinal degeneration (rd, chromosome 5), Purkinje cell degeneration (pcd, chromosome 13), and nervous (nr, chromosome 8). Segregation of Rho-specific DNA fragment differences among 50 animals from an interspecific backcross (C57BL/6J X Mus spretus) X C57BL/6J indicates that the Rho locus is 4.0 +/- 2.8 map units distal to the locus for the proto-oncogene Raf-1 and 18.0 +/- 5.4 map units proximal to the locus for the proto-oncogene Kras-2. Linkage to Raf-1 was confirmed using four sets of recombinant inbred strains. The two loci RAF1 and RHO are also syntenic on human chromosome 3, but on opposite arms.

Animals

Characterization of the cDNA coding for mouse prothrombin and localization of the gene on mouse chromosome 2.

A series of overlapping cDNAs coding for mouse prothrombin (coagulation factor II) have been isolated and the composite DNA sequence has been determined. The complete prothrombin cDNA is 1,987 bp in length [excluding the poly(A) tail] and codes for 18 bp of 5' untranslated sequence, an open reading frame coding for 618 amino acids, a stop codon, and a 3' untranslated region of 112 bp followed by a poly(A) tail. The translated amino acid sequence predicts a molecular weight of 66,087, which includes 10 residues of gamma-carboxyglutamic acid. There are five potential N-linked glycosylation sites. Mouse prothrombin is 81.4% and 77.3% identical to the human and bovine proteins, respectively. Comparison of the cDNA coding for mouse prothrombin to the human and bovine cDNAs indicates 79.9% and 76.5% identity, respectively. Amino acid residues important for the structure and function of human prothrombin are conserved in the mouse and bovine proteins. In the adult mouse and rat, prothrombin is primarily synthesized in the liver, where is constitutes 0.07% of total mRNA as determined by solution hybridization analysis. The genetic locus for mouse prothrombin, Cf-2, has been mapped using an interspecies backcross and DNA fragment differences between the two species. The prothrombin locus lies on mouse chromosome 2, 1.8 +/- 1.3 map units proximal to the catalase locus. The gene order in this region is Cen-Acra-Cf-2-Cas-1-A-Tel. This localization extends the proximal boundary of the known region of homology between mouse chromosome 2 and human chromosome 11p from Cas-1 about 2 map units toward the centromere.

Amino Acid Sequence

Chromosomal location of the gene encoding the murine acute-phase protein serum amyloid P-component (SAP).

A full-length cDNA clone, pmSAP3, encoding, the serum P component (SAP), has been used to search for DNA fragment length variation among mouse strains previously analyzed for differences in endogenous SAP levels. Three alleles were found using EcoRI-digested DNA. The finding of a single 5.4-kb fragment, allele d, in DNA from DBA/2J mice suggests the presence of a single Sap locus. Segregation of DNA fragment associated with Sapb and Sapd alleles was analyzed in three sets of recombinant inbred (RI) strains. The strain distribution pattern found for the Sap alleles was identical to that of alleles of Ly-9 in 43 individual RI strains, suggesting tight linkage with Ly-9 on mouse chromosome 1. In the BXD RI strains, the SDP of the Sap locus, defined by the difference in the endogenous SAP level, is also identical to the SDP of the DNA fragments. We propose to redesignate the Sap locus to include both the structural element defined by the DNA polymorphism and the regulatory element involved in the regulation of SAP synthesis. The Sap locus is the major genetic element contributing to the regulation of SAP production. Other genetic factors are also involved, as shown by the presence of nonparental phenotypes in the individual BXH RI strains.

Alleles

Critical analysis of the use of skeletal surveys in patients with chronic renal failure.

Skeletal radiology and bone histopathology were compared in 82 patients with renal failure. The performance of radiology in detecting lesions was assessed using interobserver studies which showed disappointing levels of agreement probably reflecting the subjective nature of the radiological signs. Radiology was very insensitive in detecting and grading hyperparathyroidism even when histology and serum biochemistry were floridly abnormal. The most useful radiographs for monitoring subperiosteal erosions and vascular and soft tissue calcification are identified.

Adolescent

Asialoglycoprotein receptor genes are linked on chromosome 11 in the mouse.

The asialoglycoprotein receptor on the hepatocyte plasma membrane recognizes galactose-terminated glycoproteins and internalizes them for subsequent degradation in lysosomes. The rat receptor, also known as rat hepatic lectin (RHL), is comprised of three protein subunits called RHL-1, RHL-2, and RHL-3; two genes code for RHL-1 and RHL-2/3, respectively. We have cloned and sequenced the gene for RHL-2/3, and demonstrated that homologous asialoglycoprotein receptor genes exist in the mouse genome. Biochemical studies have demonstrated that receptor subunits exhibit the same temporal expression during development and function in a coordinate manner. This study asks if mouse receptor genes are linked and thus could possibly respond to shared cis-acting regulatory elements. Using restriction fragment length polymorphisms (RFLPs) and recombinant inbred lines, we mapped two closely linked mouse hepatic lectin (MHL) genes to chromosome 11. Asgr is designated to name asialoglycoprotein gene loci. Coordinate regulation of this linked gene family is discussed.

Animals