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S L Naylor

Publications and source records attributed to S L Naylor.

At least 91 records · Page 5Linked to original sources

Human ferritin H and L sequences lie on ten different chromosomes.

In humans, the H (heavy) and L (light) chains of the iron-storage protein ferritin, are derived from multigene families. We have examined the chromosomal distribution of these H and L sequences by Southern analysis of hybrid cell DNA and by chromosomal in situ hybridization. Our results show that human ferritin H genes and related sequences are found on at least seven different chromosomes while L genes and related sequences are on at least three different chromosomes. Further, we have mapped the chromosomal location of expressed genes for human H and L ferritin chains and have found an H sequence which may be a useful marker for idiopathic hemochromatosis.

Animals↗

Assignment of the lactotransferrin gene to human chromosome 3 and to mouse chromosome 9.

Lactotransferrin (LTF), a member of the transferrin family of genes, is the major iron-binding protein in milk and body secretions. The amino acid sequence of LTF consists of two homologous domains homologous to proteins in the transferrin family. Recent isolation of cDNA encoding mouse LTF has expedited the mapping of both mouse and human LTF genes. Southern blot analysis of DNA from mouse-Chinese hamster and human-mouse somatic cell hybrids maps the LTF gene to mouse chromosome 9 and to human chromosome 3, respectively. Furthermore, analysis of cell hybrids containing defined segments of human chromosome 3 demonstrates that the gene is located in the 3q21-qter region. These results suggest that LTF and associated genes of the transferrin family have existed together on the same chromosomal region for 300-500 million years.

Animals↗

Chromosomal assignments of genes for tissue plasminogen activator and urokinase in mouse.

The genes encoding the two plasminogen activators, tissue plasminogen activator and urokinase, were mapped to mouse chromosomes using probes derived from the respective mouse cDNAs. DNA from mouse-Chinese hamster and mouse-rat somatic cell hybrids was digested with BamHI and EcoRI, respectively, and analyzed by Southern blot hybridization for the segregation of the two genes. Tissue plasminogen activator and urokinase cosegregated with mouse chromosomes 8 and 14, respectively. The plasminogen activator genes thus fall into two syntenic groups that are conserved in human and mouse.

Animals↗

Hemopexin is localized to human chromosome 11.

Hemopexin, a plasma protein that migrates during electrophoresis with the beta-globulins, transports free heme to sites of its catabolism in the liver. A hemopexin cDNA clone has been utilized for mapping the hemopexin (HPX) gene to human chromosome 11 in the region pter----p11 by somatic cell hybrid analysis.

Animals↗

Human gastrin-releasing peptide gene is located on chromosome 18.

Gastrin-releasing peptide (GRP), a bombesin-like peptide, increases plasma levels of gastrin, pancreatic polypeptide, glucagon, gastric inhibitory peptide, and insulin. GRP is produced in large quantities by small-cell lung cancer and acts as a growth factor for these cells. To determine if chromosomal changes in small-cell lung cancer are related to the expression of GRP, we chromosomally mapped the gene using human-mouse somatic cell hybrids. Twenty hybrids, characterized for human chromosomes, were analyzed by Southern filter hybridization of DNA digested with EcoRI. Human DNA cut with EcoRI yields a major band of 6.8 kb and a minor band of 11.3 kb. The 6.8 kb band segregated concordantly with chromosome 18 and the marker peptidase A. The chromosome 3 abnormalities seen in small-cell lung cancer do not correlate with the chromosomal location of GRP, suggesting that the elevated expression of this gene may be due to mechanisms other than chromosomal rearrangement.

Animals↗

Localization of human SAA gene(s) to chromosome 11 and detection of DNA polymorphisms.

A human serum amyloid A (SAA) cDNA was used as a probe in chromosome mapping studies to detect human SAA gene sequences in DNA isolated from human/mouse somatic cell hybrids. Southern analysis of DNA from 20 hybrid cell lines, including some with translocations of human chromosomes, placed the SAA gene(s) in the p11----pter region of chromosome 11. Screening of human DNA from unrelated individuals by Southern analysis using the SAA cDNA probe revealed restriction fragment polymorphisms for HindIII and PstI. An analysis of the segregation of these polymorphisms with other markers on the short arm of chromosome 11 should more precisely map the SAA gene(s).

Amyloid↗

Assignment of the gene for carboxypeptidase A to human chromosome 7q22----qter and to mouse chromosome 6.

A rat cDNA probe for preprocarboxypeptidase A was used to follow the segregation of the human gene for carboxypeptidase A (CPA) in 49 human X mouse somatic cell hybrids using Southern filter hybridization techniques. CPA was assigned to human chromosome 7q22----qter. Similarly, the probe was used to follow the segregation of the mouse gene for carboxypeptidase A (Cpa) in 19 mouse X Chinese hamster somatic cell hybrids. Cpa was assigned to mouse chromosome 6. The gene for carboxypeptidase A forms part of a syntenic group that is conserved in man and mouse.

Animals↗

Mapping thyrotropin beta subunit gene in man and mouse.

Thyrotropin (TSH) is composed of two subunits: alpha and beta. Previously, we have mapped the TSH alpha gene to human chromosome 6 and mouse chromosome 4. In this study we have located the human TSH beta gene on chromosome 1 and the mouse TSH beta gene to chromosome 3. These data suggest that the TSH beta gene lies in a conserved linkage group with the genes for amylase 1 and 2, nerve growth factor, and the protooncogene Nras.

Animals↗

Human insulin-related DNA sequences map to chromosomes 2 and 11.

The insulin-related hormone family consists of four known peptides: insulin, the insulin-like growth factors I and II, and relaxin. To investigate the hypothesis that the family contains additional members, we have isolated a series of human genomic clones using the insulin gene as a hybridization probe. Two of these single copy DNA sequences, hIr1 and hIr2, have been localized to chromosome 2 and 11p11----q13, respectively, by Southern blot analysis of mouse-human somatic cell hybrids, a result consistent with other evidence supporting the dispersal of the insulin gene family throughout the genome. Although a biological function for these DNA sequences has not yet been established, hIr1 and hIr2 are potentially useful as molecular probes for mapping, by analysis of restriction fragment length polymorphisms (RFLP), genetic disorders linked to chromosomes 2 or 11.

Animals↗

Characterization, mapping, and expression of the human ceruloplasmin gene.

Ceruloplasmin (CP) is a copper-binding protein in vertebrate plasma. It is the product of an intragenic triplication and is composed of three homologous domains. Oligonucleotide probes constructed according to published amino acid sequences were used to identify cDNA clones encoding human CP. Two clones, CP-1 and CP-2, differed from each other by the presence or absence, respectively, of a deduced sequence of four amino acids. The two clones provided 81% of the sequence encoding CP. Comparison of the nucleotides of the three domains of the CP coding sequence revealed internal domain homology with identity of sequences ranging from 50.1% to 56%. The nucleotide sequence of CP-2 cDNa was compared to that of a homologous human protein, clotting factor VIII, and was found to be 48% identical overall. The CP gene was mapped to human chromosome 3 by somatic-cell-hybrid analysis and to 3q25 by in situ hybridization; however, sites of hybridization to DNA on other chromosomal sites suggested additional CP-like DNA sequences in the human genome. A DNA polymorphism was detected with CP cDNA after endonuclease digestion of human DNA by Pst I. CP mRNA was detected in human liver, macrophages, and lymphocytes by in situ histohybridization.

Base Sequence↗

Mapping of the DNA locus D4S10 and the linked Huntington's disease gene to 4p16----p15.

An anonymous DNA fragment (G8) detects two restriction fragment length polymorphic alleles (RFLPs) called D4S10 in HindIII-digested human genomic DNA. This segment had been assigned to chromosome 4 and shows close linkage to the Huntington's disease gene. With in situ hybridization, we mapped D4S10 to the terminal region of the short arm of chromosome 4, localizing the Huntington's disease gene to bands 4p16----p15. This information may prove useful for the development of strategies to clone the Huntington's disease gene.

Chromosome Banding↗

Linkage of cystic fibrosis locus and polymorphic DNA markers in 14 families.

Linkage relationships between the cystic fibrosis (CF) locus and three polymorphic DNA markers were examined in 14 families, five of which were of Hispanic origin. Tight linkage was found between the CF locus and MET (maximum lod score = 7.16 at theta = .001), and between CF and pJ3.11 (maximum lod score = 3.87 at theta = .001). We observed two recombinations between CF and collagen, yielding a maximum lod score of 0.359 at theta = .125, and one recombination in the cluster CF-MET-pJ3.11. Analysis by the seriation method indicates the order COL-pJ3.11-CF-MET.

Cystic Fibrosis↗

Genes for insulin I and II, parathyroid hormone, and calcitonin are on rat chromosome 1.

Insulin, parathyroid hormone, and calcitonin are polypeptide hormones that regulate important physiological processes in target tissues. Rat genes encoding each hormone were chromosomally assigned to rat chromosome 1. Both rats and mice have two insulin genes (I and II). However, in contrast to mice in which insulin I and II are asyntenic, rat insulin I and II were both localized to chromosome 1. This study identifies a conserved syntenic group on rat chromosome 1, and implies that mouse insulin I and II genes were chromosomally separated after rats and mice diverged 20-35 million years ago.

Animals↗

Human ApoB-100 gene resides in the p23----pter region of chromosome 2.

Human apolipoprotein (apo) B-100 is the major apolipoprotein of low density lipoproteins (LDL) and the principal ligand for interaction with the LDL receptor. The gene for apoB-100 has been localized to the p23----pter region of chromosome 2 by filter hybridization analysis with radiolabelled apoB-100 cDNA probes and human-mouse somatic cell hybrids containing chromosome 2 translocations. Other genes at the end of the short arm of chromosome 2 include acid phosphatase, proopiomelanocortin complex, malate dehydrogenase, and N-myc, the latter gene has been previously localized to the same bands (2p23----pter) as the apoB-100 gene. The localization of the apoB-100 gene to the p23----pter region of chromosome 2 completes the genomic organizational relationship of the LDL receptor and the two apolipoprotein ligands for the LDL receptor, apoE and apoB-100; the LDL receptor and apoE having been previously localized to chromosome 19.

Animals↗

Human lymphotoxin and tumor necrosis factor genes: structure, homology and chromosomal localization.

Human Tumor Necrosis Factor and Lymphotoxin are cytotoxic proteins which have similar biological activities and share 30 percent amino acid homology. The single copy genes which encode these proteins share several structural features: each gene is approximately three kilobase pairs in length and is interrupted by three introns. In addition, these genes are closely linked and have been mapped to human chromosome 6. However, only the last exons of both genes, which code for more than 80 percent of each secreted protein, are significantly homologous (56 percent).

Amino Acid Sequence↗

Localization of the human prealbumin gene to chromosome 18.

A human liver cDNA library was screened using an oligonucleotide probe based on the amino acid sequence of human prealbumin. The cDNA insert of one positive clone was sequenced and found to contain the entire coding sequence of human prealbumin plus untranslated 5' and 3' regions. This cDNA was used to probe DNA from a panel of mouse/human somatic cell hybrids. Only those hybrids containing human chromosome 18 showed the human-specific hybridization pattern, thereby localizing the human prealbumin gene to this chromosome.

Amino Acid Sequence↗