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S L Naylor

Publications and source records attributed to S L Naylor.

At least 37 records · Page 2Linked to original sources

Isolation of the human semaphorin III/F gene (SEMA3F) at chromosome 3p21, a region deleted in lung cancer.

Small cell lung cancer (SCLC) has been correlated with a deletion in the short arm of chromosome 3, with the region 3p21 being lost from one homolog in almost all cases. Two SCLC cell lines have homozygous deletions in 3p21, and these deletions overlap with a fragment of chromosome 3 that has tumor suppression activity in vivo. We have isolated some cDNA clones from this region that are homologous to the genes constituting the semaphorin family. They represent a novel human semaphorin, termed sema III/F (HGMW-approved symbol SEMA3F), which is expressed as a 3.8-kb transcript in a variety of cell lines and tissues; it is detected as early as Embryonic Day 10 in mouse development. There is high expression in mammary gland, kidney, fetal brain, and lung and lower expression in heart and liver. Although there is reduced expression of this gene in several SCLC lines, no mutations were found. This semaphorin homolog has characteristics of a secreted member of the semaphorin III family, with 52% identity with mouse semaphorin E and 49% identity with chicken collapsin/semaphorin D.

Amino Acid Sequence↗

Structural characterization and fine chromosomal mapping of the human P2Y1 purinergic receptor gene (P2RY1).

Using P2Y1 specific oligonucleotide primers in a Polymerase Chain Reaction on human genomic DNA, we have amplified a region encoding the P2Y1 receptor Restriction analysis and Southern hybridization of the PCR product revealed that the entire open reading frame of the human P2Y1 receptor is coded by an intronless gene. We have previously localized the P2Y1 receptor gene to human chromosome 3. The gene was further localized to a region of chromosome 3 using a subchromosomal hybrid panel containing different segments of chromosome 3. Based on the specific PCR product obtained and its Southern hybridization to the human P2Y1 receptor cRNA, the P2Y1 receptor gene was mapped to human chromosome 3q25.

Animals↗

Linkage and cytogenetic mapping of a CAG repeat containing human cDNA to 3p24.2-p22.

A trinucleotide (CAG)n repeat containing cDNA was isolated from a human cDNA library and sequenced. The locus was mapped by linkage analysis in the CEPH families and by cytogenetic analysis to 3p24.2-p22. We have additionally excluded this gene as a candidate for small cell lung carcinoma by the analysis of cell lines carrying homozygous deletions for the 3p chromosomal region.

Chromosome Mapping↗

Mapping 638 STSs to regions of human chromosome 3.

The initial step of mapping STSs to chromosome 3 has been by mapping to a reference panel of 21 somatic cell hybrids containing fragments of chromosome 3. In this study we map 638 STSs to 23 bins on chromosome 3. The bin information greatly facilitates further mapping by radiation hybrids and YAC clones.

Chromosome Mapping↗

Characterization of the mouse loricrin gene: linkage with profilaggrin and the flaky tail and soft coat mutant loci on chromosome 3.

Loricrin is the major component of a specialized structure, termed the cornified cell envelope, that is formed beneath the plasma membrane of stratified squamous epithelial cells and is coexpressed with profilaggrin in terminally differentiating epidermal keratinocytes. Full-length cDNAs for both mouse and human loricrin have been cloned and characterized, as has the human gene. Here we report the isolation and characterization of the mouse loricrin gene. The gene has a simple structure consisting of a single intron of 1091 bp within the 5' noncoding sequence and an uninterrupted open reading frame. Using PCR analyses of DNAs isolated from mouse x Chinese hamster somatic cell hybrids, we have mapped both the loricrin and the profilaggrin genes to chromosome 3. Genetic linkage analysis has shown that mouse loricin and profilaggrin lie within 1.5 +/- 1.1 centimorgans of each other. We have further shown that both genes map in the vicinity of the flaky tail (ft) and soft coat (soc) loci. These mouse mutants exhibit a number of changes in their integument, suggesting that abnormalities in these genes may contribute to the mutant phenotype.

Amino Acid Sequence↗

Assignment of xeroderma pigmentosum group C (XPC) gene to chromosome 3p25.

The human gene XPC (formerly designated XPCC), which corrects the repair deficiency of xeroderma pigmentosum (XP) group C cells, was mapped to 3p25. A cDNA probe for Southern blot hybridization and diagnostic PCR analyses of hybrid clone panels informative for human chromosomes in general and portions of chromosome 3 in particular produced the initial results. Fluorescence in situ hybridization utilizing both a yeast artificial chromosome DNA containing the gene and XPC cDNA as probes provided verification and specific regional assignment. A conflicting assignment of XPC to chromosome 5 is discussed in light of inadequacies in the exclusive use of microcell-mediated chromosome transfer for gene mapping.

Animals↗

Two novel human serine/threonine kinases with homologies to the cell cycle regulating Xenopus MO15, and NIMA kinases: cloning and characterization of their expression pattern.

Using polymerase chain reaction (PCR)-based methods, we have isolated cDNA clones of two new members of serine/threonine kinases, STK1 and STK2, from a cDNA library constructed from the BT-20 human breast cancer cell line. STK1 is transcribed as a 1.4 kilobase (kb) mRNA encoding for a protein of 346 amino acids. Based on amino acid sequence analysis, STK1 is 86% identical to the Xenopus p40mo15, a cdc2-related serine/threonine kinase recently found to be the activating kinase for p34cdc2 and p33cdk2. Thus, STK1 is most likely the human homologue of MO15. An alternatively spliced STK1 message expressed variably in cell lines and in primary carcinomas generates a predicted 58 amino acid protein that lacks the kinase domain. STK2 is transcribed into a 4.0 kb mRNA encoding for an 841 residue protein which exhibits 50% identity in the kinase domain with the mouse nek1 gene product, the relative of the fungal G2-M regulator, nimA. STK1 and STK2 display a variable pattern of expression among a series of primary carcinomas as well as cancer cell lines. Both STK1 and STK2 were expressed at the highest levels in the heart but were also detected in all other organs tested. In embryonal tissues, lower levels of expression were noted. Using cell cycle inhibitors, we have shown that both STK1 and STK2 mRNA levels remain relatively invariant through the cell cycle. Chromosomal assignment has localized STK1 on chromosome 2pcen-2p15, a region implicated in hereditary non-polyposis colorectal carcinoma, and STK2 on chromosome 3p21.1, a region frequently showing chromosomal alterations in renal cells carcinomas.

Amino Acid Sequence↗

Characterization of NIGMS human/rodent somatic cell hybrid mapping panel 2 by PCR.

NIGMS human somatic cell hybrid mapping panel 2 was tested for specific markers for each human chromosome. Several discrepancies with the reported chromosome content were found by screening with PCR primers. Our results indicated that there were additional chromosomal fragments present in some of the cell lines and that a few of the hybrids had lost part of the reported chromosome.

Animals↗

Dinucleotide repeat loci contribute highly informative genetic markers to the human chromosome 2 linkage map.

Microsatellite repeat loci can provide informative markers for genetic linkage. Currently, the human chromosome 2 genetic linkage map has very few highly polymorphic markers. Being such a large chromosome, it will require a large number of informative markers for the dense coverage desired to allow disease genes to be mapped quickly and accurately. Dinucleotide repeat loci from two anonymous chromosome 2 genomic DNA clones were sequenced so that oligonucleotide primers could be designed for amplifying each locus using the polymerase chain reaction (PCR). Five sets of PCR primers were also generated from nucleotide sequences in the GenBank Database of chromosome 2 genes containing dinucleotide repeats. In addition, one PCR primer pair was made that amplifies a restriction fragment length polymorphism on the TNP1 gene (Hoth and Engel, 1991). These markers were placed on the CEPH genetic linkage map by screening the CEPH reference DNA panel with each primer set, combining these data with those of other markers previously placed on the map, and analyzing the combined data set using CRI-MAP and LINKAGE. The microsatellite loci are highly informative markers and the TNP1 locus, as expected, is only moderately informative. A map was constructed with 38 ordered loci (odds > or = 1000:1) spanning 296 cM (male) and 476 cM (female) of chromosome 2 compared with 306 cM (male) and 529 cM (female) for a previous map of 20 markers.

Animals↗

A homozygous deletion on chromosome 3 in a small cell lung cancer cell line correlates with a region of tumor suppressor activity.

Small cell lung cancer (SCLC) tumors frequently display deletions on the short arm of chromosome 3 suggesting the existence of a 'tumor suppressor' gene within that region whose functional inactivation may be involved in tumorigenesis. Recently, a hybrid, HA(3)BB9F, was identified that contains a small fragment of human chromosome 3 of approximately 2 Mb on a mouse (A9) background (Killary et. al., 1992). This hybrid was utilized to define a functional tumor suppressor gene within 3p22-p21 which could suppress the tumorigenic properties of the mouse fibrosarcoma cell line. The existence of a tumor suppressor gene in the region 3p22-p21 is supported by the present report which describes the assessment of 89 SCLC and 32 non-SCLC lung cancer tumors and cell lines for the existence of a homozygous deletion(s) at 43 loci on the short arm of chromosome 3. One of the SCLC cell lines was found to harbor a homozygous deletion involving the loss of five markers on chromosome 3p. All five of the markers map to the region 3p21.3-p21.2 and four of the five markers are located within the chromosome 3 fragment exhibiting properties of tumor suppression in the HA(3)BB9F hybrid. The other tumors analysed all retained at least one copy of each of the markers assessed.

Carcinoma, Non-Small-Cell Lung↗

Definition of a tumor suppressor locus within human chromosome 3p21-p22.

Cytogenetic abnormalities and high-frequency allele losses involving the short arm of human chromosome 3 have been identified in a variety of histologically different neoplasms. These findings suggest that a tumor-suppressor gene or genes may be located in the region of 3p14-p25, although there has been no definitive functional proof for the involvement of a particular region of 3p. We report a rapid genetic assay system that has allowed functional analysis of defined regions of 3p in the suppression of tumorigenicity in vivo. Interspecific microcell hybrids containing fragments of chromosome 3p were constructed and screened for tumorigenicity in athymic nude mice. Hybrid clones were obtained that showed a dramatic tumor suppression and contained a 2-megabase fragment of human chromosomal material encompassing the region 3p21 near the interface with 3p22. With these hybrid clones, we have defined a genetic locus at 3p21-p22 intimately involved in tumor suppression.

Adenine Phosphoribosyltransferase↗

Mouse UDP-GlcNAc: dolichyl-phosphate N-acetylglucosaminephosphotransferase. Molecular cloning of the cDNA, generation of anti-peptide antibodies and chromosomal localization.

A cDNA encoding UDP-GlcNAc-dolichyl-phosphate N-acetylglucosaminephosphotransferase (GPT; EC 2.7.8.15), an enzyme that catalyses the first step in the synthesis of dolichol-linked oligosaccharides, was isolated from mRNA prepared from mouse mammary glands. The cDNA contains an open reading frame that codes for a protein of 410 amino acids with a predicted molecular mass of 46.472 kDa. Mouse GPT has two copies of a putative dolichol-recognition sequence that has so far been identified in all eukaryotic enzymes which interact with dolichol, and four consensus sites for asparagine-linked glycosylation. It shows a high degree of conservation with yeast and hamster GPTs at the amino acid level. The mouse GPT cDNA recognized a single mRNA species of about 2 kb in mouse mammary glands when used as a probe in Northern blot analysis. An antiserum raised against a 15-residue peptide, derived from the predicted amino acid sequence of the cloned mouse cDNA, specifically precipitated the activity of GPT from solubilized mouse mammary gland microsomes, and detected a protein of about 48 kDa on Western blot. This size is in good agreement with that predicted from the cDNA sequence, and also with that (46 and 50 kDa) of purified bovine GPT. With the use of a panel of mouse/hamster somatic-cell hybrids and a specific probe derived from the 3'-non-coding region of the mouse cDNA, the GPT gene was mapped to mouse chromosome 17.

Amino Acid Sequence↗