Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Nucleotide Mapping”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

Genetic mapping of the adenine nucleotide translocase-2 gene (Ant2) to the mouse proximal X chromosome.

Adenine nucleotide translocases are mitochondrial membrane proteins encoded by a small dispersed multigene family. We have previously cloned cDNAs derived from the mouse adenine nucleotide translocase-1 and -2 genes (Ant1 and Ant2) and assigned the loci to mouse chromosomes 8 and X, respectively. Here we describe the genomic organization of the Ant2 gene and its regional map position on the X chromosome, which was determined through linkage analysis using an interspecific backcross between Mus musculus and Mus spretus inbred strains. Ant2 cosegregates with DXMit49 and DXMit50 and lies distal to Agtr2 in the proximal region of the mouse X chromosome. This map assignment further defines a region of conserved synteny between human Xq22-q25 and the mouse proximal X chromosome.

Animals↗

Characterization of preearly genes in the terminal repetition of bacteriophage BF23 DNA by nucleotide sequencing and restriction mapping.

A finer restriction map of the terminal repetition of bacteriophage BF23 DNA was determined and used to localize a 3.4-kbp deletion in the terminal repetition and to determine the physical location of preearly gene A2-A3. The nucleotide sequence of gene A2-A3 was determined and shown to code for a protein of 125 amino acids with no indication of a membrane transport sequence. The beginning of an adjacent gene, probably gene A1, was also sequenced.

Amino Acid Sequence↗

Identification and characterization of a novel cyclic nucleotide phosphodiesterase gene (PDE9A) that maps to 21q22.3: alternative splicing of mRNA transcripts, genomic structure and sequence.

Cyclic nucleotide-specific phosphodiesterases (PDEs) play an essential role in signal transduction by regulating the intracellular concentration of second messengers (cAMP and cGMP). We have identified and made an initial characterization of a full-length cDNA encoding a novel human cyclic nucleotide phosphodiesterase, PDE9A. At least four different mRNA transcripts (PDE9A1, A2, A3, A4) are produced as a result of alternative splicing of 5' exons, potentially changing the N-terminal amino acid sequences of the encoded proteins. All these predicted proteins would contain a 3',5'-cyclic nucleotide phosphodiesterase signature motif (Prosite no. PDOC00116). Northern blot analysis revealed several mRNA species of approximately 2.4 kb with varying expression patterns and intensities in most tissues examined, except blood. We have also isolated the mouse homolog of the human PDE9A2 mRNA transcript, pde9A2. The human and mouse isoforms have 93 and 83% sequence identity at the amino acid and nucleotide levels, respectively. PDE9A was mapped to 21q22.3, between TFF1 and D21S360. Comparison of the PDE9A1 cDNA with the genomic sequence from the region revealed that the gene is split into 20 exons that extend over 122 kb. Comparison of the physical map of the region and the genomic sequence further refines the mapping, with D21S113 being derived from intron 15. Several genetic disorders map to 21q22.3, including one form of bipolar affective disorder. Since functional disturbances in intraneuronal signal transmission via second messengers play an important role in the pathophysiology of affective disorders, PDE9A is a strong candidate for such a role by position and function.

3',5'-Cyclic-AMP Phosphodiesterases↗

The human alpha-fetoprotein gene. Sequence organization and the 5' flanking region.

The human alpha-fetoprotein (AFP) gene was isolated into three overlapping clones in bacteriophage lambda vectors and its sequence organization analyzed by restriction endonuclease mapping and nucleotide sequencing. The human AFP gene is about 20 kilobase pairs long and contains 15 exons and 14 introns. The overall organization of the human AFP gene is similar to that of the mouse AFP gene, with all but two exons showing identical sizes. Nucleotide sequences at all exon/intron junctions display similarity to the consensus boundary sequence (Breathnach, R., and Chambon, P. (1981) Annu. Rev. Biochem. 50, 349-383), with the GT-AG rule applied to the splicing point. The cap site maps 44 nucleotides upstream from the translation initiation site. The "TATA box" is located 27 nucleotides upstream from the putative cap site and is flanked by sequences with dyad symmetry. The TATA box can thus be placed in the loop portion of a possible stem-loop structure formed by intrastrand base-pairing. Other characteristic nucleotide sequences in the 5' flanking region include a CCAAC pentamer, a 14-base pair (bp) enhancer-like sequence, and a 9-bp sequence homologous to the glucocorticoid responsive element. A long (90 bp) direct repeat and several alternating purine/pyrimidine sequences are also present in the 5' flanking region. A 736-bp sequence of the 5' flanking region adjacent to the cap site of the human AFP gene shows a 61% similarity with the corresponding region of the mouse AFP gene. There are two Alu family sequences and two poly(dT-dG) repeats in the human AFP gene that show different distribution patterns from those in the mouse AFP gene.

Amino Acid Sequence↗

Family-based analysis using a dense single-nucleotide polymorphism-based map defines genetic variation at PSORS1, the major psoriasis-susceptibility locus.

Psoriasis is a common skin disorder of multifactorial origin. Genomewide scans for disease susceptibility have repeatedly demonstrated the existence of a major locus, PSORS1 (psoriasis susceptibility 1), contained within the major histocompatibility complex (MHC), on chromosome 6p21. Subsequent refinement studies have highlighted linkage disequilibrium (LD) with psoriasis, along a 150-kb segment that includes at least three candidate genes (encoding human leukocyte antigen-C [HLA-C], alpha-helix-coiled-coil-rod homologue, and corneodesmosin), each of which has been shown to harbor disease-associated alleles. However, the boundaries of the minimal PSORS1 region remain poorly defined. Moreover, interpretations of allelic association with psoriasis are compounded by limited insight of LD conservation within MHC class I interval. To address these issues, we have pursued a high-resolution genetic characterization of the PSORS1 locus. We resequenced genomic segments along a 220-kb region at chromosome 6p21 and identified a total of 119 high-frequency SNPs. Using 59 SNPs (18 coding and 41 noncoding SNPs) whose position was representative of the overall marker distribution, we genotyped a data set of 171 independently ascertained parent-affected offspring trios. Family-based association analysis of this cohort highlighted two SNPs (n.7 and n.9) respectively lying 7 and 4 kb proximal to HLA-C. These markers generated highly significant evidence of disease association (P<10-9), several orders of magnitude greater than the observed significance displayed by any other SNP that has previously been associated with disease susceptibility. This observation was replicated in a Gujarati Indian case/control data set. Haplotype-based analysis detected overtransmission of a cluster of chromosomes, which probably originated by ancestral mutation of a common disease-bearing haplotype. The only markers exclusive to the overtransmitted chromosomes are SNPs n.7 and n.9, which define a 10-kb PSORS1 core risk haplotype. These data demonstrate the power of SNP haplotype-based association analyses and provide high-resolution dissection of genetic variation across the PSORS1 interval, the major susceptibility locus for psoriasis.

Case-Control Studies↗

Genetic maps of microsatellite and single-nucleotide polymorphism markers: are the distances accurate?

Genetic maps play an important role in gene mapping. Inaccurate genetic maps can hinder gene mapping by biasing lod scores and reducing the power to map a trait to a particular region. Although sequence-based physical maps can provide a unique order for markers, they do not provide information on genetic map distances. By simulation studies, I investigated how many meioses are necessary to accurately estimate genetic map distances for maps constructed from microsatellite and single-nucleotide polymorphism (SNP) markers for various intermarker distances and marker heterozygosity. To evaluate the accuracy of the generated genetic maps, the length of the 95% confidence interval for intermarker genetic distances was examined. In addition, the power to separate two adjacent markers by a nonzero map distance was investigated. The number of meioses necessary to accurately estimate map distances depends greatly not only on intermarker distances but also on marker heterozygosity. For example, for a genetic map with intermarker distances of 0.5 cM generated with 1,000 meioses, when marker heterozygosity was high (0.90), for 96% of the markers there was a nonzero map distance between adjacent markers. However, when marker heterozygosity was low (0.32), only 48% of the markers mapped to a unique position. For identical numbers of meioses and intermarker distances, genetic maps constructed from microsatellite markers will be more precise than maps assembled from SNP markers, due to the higher levels of heterozygosity for microsatellite markers.

Adult↗

In vivo mapping of the human adenine nucleotide translocator-2 (ANT2) promoter provides support for regulation by a pair of proximal Sp1-activating sites and an upstream silencer element.

Regulatory factors bound to the human adenine nucleotide translocator-2 (ANT2) promoter have been mapped in HeLa cells by in vivo DNase I protection and ligation-mediated PCR amplification. Protein binding was detected at only three sites within the extended promoter region (to nt -703). One, starting at nt -61 and covering the TATA box and transcription start, most probably represents occupation by the transcription-initiation machinery. A repeated Sp1 element determined by in vitro studies to be the major activation element for the promoter was also protected in vivo on nucleotides responsible for strong binding to the zinc fingers. Occupation of two additional upstream Sp1 elements was not observed. The third site occupied in vivo was identified previously by in vitro studies as a unique silencer element. Treatment of cells with trichostatin A to induce hyperacetylation released the silencer-binding protein after 1 h, but had no effect on the Sp1-activating elements. Prolonged treatment (24 h) displaced Sp1 from the activating elements. These findings confirm and extend in vitro studies indicating that regulation of the ANT2 promoter is most probably exerted through a single pair of proximal Sp1-activating elements and an upstream silencer, and that chromatin organization plays a role in the interaction between the two.

Base Sequence↗

Sequence duplication and internal deletion in the integrated human papillomavirus type 16 genome cloned from a cervical carcinoma.

Integrated human papillomavirus type 16 (HPV16) sequences were cloned from a cervical carcinoma and analyzed by restriction mapping and nucleotide sequencing. The viral integration sites were mapped within the E1 and E2 open reading frames (ORFs). The E4 and E5 ORFs were entirely deleted. An internal deletion of 376 base pairs (bp) was found disrupting the L1 and L2 ORFs. Sequencing analysis showed that an AGATGT/ACATCT inverted repeat marked the deletion junction with two flanking direct repeats 14 and 8 bp in length. A 1,330-bp sequence duplication containing the long control region (LCR) and the E6 and E7 ORFs was also found. The duplication junction was formed by two 24-bp direct repeats with 79% (19 of 24) homology located within the LCR and the E2 ORF of the prototype viral genome, respectively. This observation leads us to propose that the initial viral integration involved an HPV16 dimer in which the direct repeats in tandem units recombined, resulting in reiteration of only a portion of the original duplication. A guanosine insertion between nucleotides 1137 and 1138 created a continuous E1 ORF which was previously shown to be disrupted. Results from this study indicate that sequence reiteration and internal deletion in the integrated, and possibly in the episomal, HPV16 genome are influenced by specific nucleotide sequences in the viral genome. Moreover, reiteration of the LCR/E6/E7 sequences further supports the hypothesis that the E6/E7 ORFs may code for oncogenic proteins and that regulatory signals in the LCR may play a role in cellular transformation.

Base Sequence↗

Genomic mapping with I-Ceu I, an intron-encoded endonuclease specific for genes for ribosomal RNA, in Salmonella spp., Escherichia coli, and other bacteria.

Construction of physical maps of genomes by pulsed-field gel electrophoresis requires enzymes which cut the genome into an analyzable number of fragments; most produce too many fragments. The enzyme I-Ceu I, encoded by a mobile intron in the chloroplast 23S ribosomal RNA (rrl) gene of Chlamydomonas eugametos, cuts a 26-bp site in the rrl gene. This enzyme digests DNA of Salmonella typhimurium at seven sites, each corresponding to one of the rrl genes of the rrn operons, but at no other site. These seven fragments were located on the previously determined Xba I physical map, and the I-Ceu I sites, and thus the rrn genes of S. typhimurium, were mapped on the 4800-kb chromosome. Escherichia coli K-12 also yields seven fragments of sizes similar to those of S. typhimurium, indicating conservation of rrn genes and their location, and a chromosome size of 4600 kb. The sizes of the E. coli fragments are close to the size predicted from restriction maps and nucleotide sequence. The I-Ceu I maps of Salmonella enteritidis, Salmonella paratyphi A, B, C, and Salmonella typhi were deduced after digesting genomic DNA and I-Ceu I and probing with DNA of S. typhimurium; the data indicated strong conservation of rrn gene number and position and genome sizes up to 4950 kb. Digestion of DNA of other bacteria (species of Haemophilus, Neisseria, Proteus, and Pasteurella) suggested that only rrn genes are cut in all these species. I-Ceu I digestion followed by pulsed-field gel electrophoresis is a powerful tool for determining genome structure and evolution.

Base Sequence↗

Human papillomavirus types 6 and 11 mRNAs from genital condylomata acuminata.

We have identified and mapped a number of RNA species of human papillomavirus types 6 and 11 from condylomata acuminata by the electron microscopic R-loop technique. Each of the early (E)- and late (L)-region open reading frames (ORFs) deduced from the DNA sequences was represented in one or more transcripts. In addition, RNA species that could encode the modulator of DNA replication and the repressor of transcription, functions recently identified in the genetically similar bovine papillomavirus type 1, were also detected. Some ORFs were 5' proximal in one or more transcripts, whereas others were not 5' proximal in any species, suggesting that internal initiation of translation might be required to gain access to these latter ORFs. Virtually all transcripts had their 5' ends located in the E region and were polyadenylated at one of two sites, i.e., at the end of the E region or at the end of the L region. The great majority of the RNAs were derived from the E region of the genome, with one species approximately 50 to 100 times more abundant than the others. For most of the RNAs, the 5' end mapped near nucleotide 700; minor populations had 5' ends near nucleotide 100 or 1200. By correlating our mapping data with the genomic DNA sequences as well as available RNA structures and cDNA sequences of several papillomaviruses, we predict a number of mRNA splice donor and acceptor sites and suggest that the papillomaviruses have sophisticated usage of ORFs through alternative promoters, mRNA splice sites, and polyadenylation sites.

Anus Neoplasms↗

Initiation and termination of duck hepatitis B virus DNA synthesis during virus maturation.

We characterized a number of important features of the structure of the cohesive overlap region of the DNA genome of duck hepatitis B virus. The 5'-terminal nucleotide of minus-strand DNA was localized to nucleotide 2537, a G residue within the 12-base repeat sequence DR1. This G residue was shown to be the site of a covalent linkage to a protein, consistent with speculation that this protein is the primer of minus-strand synthesis, which occurs by reverse transcription. The 3' terminus of the minus strand was heterogeneous, being mapped to nucleotides 2530 and 2531, indicating that the minus strand is terminally redundant by seven or eight bases and ends at the putative 5' end of the transcribed RNA template (pregenome) for reverse transcription. We previously demonstrated that the presumptive RNA primer of plus-strand synthesis remains attached to plus-strand DNA during virus maturation; moreover, the sequence of this primer suggested an origin from the 5' end of the pregenome (J.-M. Lien, C. E. Aldrich, and W. S. Mason, J. Virol. 57:229-236, 1986). We show here that over 75% of plus-strand primers are capped, further supporting the idea that these primers are uniquely derived from the 5' end of the pregenome. Finally, we found that seemingly mature duck hepatitis B virus genomes are incomplete by at least 12 bases, in that the 12-base repeat sequence DR2 is not copied into plus-strand DNA during virus maturation. Since DR2 in virion DNA is duplexed with the RNA primer of plus-strand synthesis, it is possible that the failure to make complete plus strands is due to an inability of the viral DNA polymerase to carry out a displacement of the bound RNA primer.

Animals↗

Alterations in the U3 region of the long terminal repeat of an infectious thymotropic type B retrovirus.

We isolated and characterized a type B thymotropic retrovirus (DMBA-LV) which is highly related to mouse mammary tumor virus (MMTV) isolates and which induces T-cell thymomas with a high incidence and a very short latent period. Regions of nonhomology between the DMBA-LV genome and the MMTV genome were identified by heteroduplex mapping and nucleotide sequence studies. In the electron microscope heteroduplex mapping studies the EcoRI-generated 5' and 3' fragments of the DMBA-LV genome were compared with the corresponding fragments of the MMTV (C3H and GR) genome isolated from mammary tumors. The results indicated that DMBA-LV contained a region of nonhomologous nucleotide sequences in the 3' half of the U3 region of the long terminal repeat (LTR). Nucleotide sequence studies confirmed these results and showed that in this region 440 nucleotides of the MMTV (C3H) sequences were deleted and substituted with a segment of 122 nucleotides. This substituted segment in the form of a tandem repeat structure contained nucleotide sequences derived exclusively from sequences which flanked the substitution loop. The distal glucocorticoid regulatory element was unaltered, and two additional copies of the distal glucocorticoid regulatory element-binding site were present in the substituted region. The restriction endonuclease map of the reconstructed molecular clone of DMBA-LV was identical to that corresponding to unintegrated linear DMBA-LV DNA present in DMBA-LV-induced tumor cell lines. Since the nucleotide sequences of the LTRs present in four different DMBA-LV proviral copies isolated from a single thymoma were identical, we concluded that they were derived from the same parental virus and that this type B retrovirus containing an alteration in the U3 region of its LTR could induce thymic lymphomas. Thus, DMBA-LV represents the first example of a productively replicating type B retrovirus that contains an LTR modified in the U3 region and that has target cell and disease specificity for T cells.

Base Sequence↗

Isolation of cDNAs encoding a substrate for protein kinase C: nucleotide sequence and chromosomal mapping of the gene for a human 80K protein.

An acidic phosphoprotein of Mr 80,000, the 80K protein, is a substrate for protein kinase C in fibroblasts and epidermal carcinoma cells. We purified the 80K protein from human squamous carcinoma Ca9-22 cells and fractionated it into two distinct molecular species, designated the 80K-L and 80K-H proteins. The amino acid sequences of the NH2-terminal region and cyanogen bromide-cleaved fragments of the 80K-H protein were determined and a corresponding oligonucleotide sequence was synthesized. Using this as a probe, two cDNA clones, lambda 80H-1 and lambda 80H-2, were selected from a lambda gt10 cDNA library from human A431 cells. The nucleotide sequence has an open reading frame of 1581 nucleotides encoding a protein of 527 amino acids. The deduced amino acid sequence revealed an extremely Glu-rich region. RNA blot analysis with the lambda 80H-1 cDNA clone detected two polyadenylated transcripts of 2.3 and 3.5 kb in Ca9-22 cells. Spot blot hybridization using flow-sorted human chromosomes provided evidence that the gene (G19P1) encoding 80K-H protein maps to human chromosome 19.

Amino Acid Sequence↗

Cloning, nucleotide sequence, mutagenesis, and mapping of the Bacillus subtilis pbpD gene, which codes for penicillin-binding protein 4.

The gene encoding penicillin-binding protein 4 (PBP 4) of Bacillus subtilis, pbpD, was cloned by two independent methods. PBP 4 was purified, and the amino acid sequence of a cyanogen bromide digestion product was used to design an oligonucleotide probe for identification of the gene. An oligonucleotide probe designed to hybridize to genes encoding class A high-molecular-weight PBPs also identified this gene. DNA sequence analysis of the cloned DNA revealed that (i) the amino acid sequence of PBP 4 was similar to those of other class A high-molecular-weight PBPs and (ii) pbpD appeared to be cotranscribed with a downstream gene (termed orf2) of unknown function. The orf2 gene is followed by an apparent non-protein-coding region which exhibits nucleotide sequence similarity with at least two other regions of the chromosome and which has a high potential for secondary structure formation. Mutations in pbpD resulted in the disappearance of PBP 4 but had no obvious effect on growth, cell division, sporulation, spore heat resistance, or spore germination. Expression of a transcriptional fusion of pbpD to lacZ increased throughout growth, decreased during sporulation, and was induced approximately 45 min into spore germination. A single transcription start site was detected just upstream of pbpD. The pbpD locus was mapped to the 275 to 280 degrees region of the chromosomal genetic map.

Amino Acid Sequence↗

Temporal gene regulation of the channel catfish virus (Ictalurid herpesvirus 1).

To identify promoter regions that impart differential temporal regulation of channel catfish virus (CCV) genes, the transcriptional kinetics of an immediate-early gene and prospective early and late genes were characterized. A cDNA clone, designated IE3C, representing a third immediate-early transcript was identified. The 5' end of the IE3C transcript was mapped to nucleotides 15,368 and 131,043 in the terminal repeat regions of the CCV genome. The full length of the transcript represented by the IE3C clone is 1,412 bp, and it most likely codes for the protein specified by open reading frame (ORF) 12. The putative product of ORF12 contains a consensus RING finger metal binding motif (C3HC4 structure). Temporal expression studies, in conjunction with protein synthesis and DNA replication inhibition, demonstrated that the IE3C transcript belongs to an immediate-early kinetic class, the ORF5 transcript is a member of the early kinetic class, and ORF39 and ORF46 are true late-kinetic-class genes. Additionally, we demonstrated that ORF38 transcription overlaps ORF39 and the products presumably share the same poly(A) signal. The 5' ends of the transcripts encoding ORF38, ORF39, and ORF46 were mapped to nucleotides 44,862, 45,254, and 59,644, respectively, and potential transcriptional control elements were located.

Amino Acid Sequence↗

Isomorphism between cell and human languages: molecular biological, bioinformatic and linguistic implications.

The concept of cell language has been defined in molecular terms. The molecule-based cell language is shown to be isomorphic with the sound- and visual signal-based human language with respect to ten out of the 13 design features of human language characterized by Hockett. Biocybernetics, a general molecular theory of living systems developed over the past two and a half decades, is found to provide a physical theory underlying the phenomenon of cell language. The concept of cell language integrates bioenergetics and bioinformatics on the one hand and reductionistic and holistic experimental data on the other to account for living processes on the molecular level. The isomorphism between cell and human languages suggests that the DNA of higher eucaryotes contains two classes of genes--structural genes corresponding to the lexicon and 'spatiotemporal genes' corresponding to the grammar of cell language. The former is located in coding regions of DNA and the latter is predicted to reside primarily in noncoding regions. The grammar of cell language is identified with the mapping of the nucleotide sequences of DNA onto its 4-dimensional folding patterns that control the spatiotemporal evolution of gene expression. Such a mapping has been referred to as the second genetic code, in contrast to the first genetic code which maps nucleotide triplets onto amino acids. The cell language theory introduces into biology the linguistic principle of 'rule-governed creativity,' leading to the formulation of the concept of 'rule-governed creative molecules' or 'creations.' This concept sheds new light on molecular biology, bioinformatics, protein folding, and developmental biology. In addition, the cell language theory suggests that human language is ultimately founded on cell language.

Cell Biology↗

Nucleotide sequencing and transcriptional mapping of the Orgyia pseudotsugata multicapsid nuclear polyhedrosis virus p10 gene.

A 32P-labeled cloned DNA fragment (AcMNPV HindIII-Q) containing one of the repeated sequences and a portion of the p10 gene from Autographa californica multicapsid nuclear polyhedrosis virus (AcMNPV) was used to probe Southern blots containing restriction endonuclease digests of Orgyia pseudotsugata muticapsid nuclear polyhedrosis virus (OpMNPV) DNA. A single 3.6-kb fragment, OpMNPV HindIII-Q, was hybridized. The OpMNPV HindIII-Q fragment was cloned into pUC-18, mapped with restriction endonucleases, and reprobed with the AcMNPV HindIII-Q fragment. A small region of ca. 700 bp, near the left end of the cloned fragment, was cross-hybridized. DNA sequencing in this region revealed an open reading frame of 279 bp which shares detectable homology with the p10 gene of AcMNPV. The sequences downstream from the p10 gene in both viruses also contain long open reading frames which share homology. Northern blot analysis of RNA from OpMNPV infected O. leucostigma cells was used to define the temporal and spatial organization of transcripts from this region. S1 analysis of both termini of the major p10 mRNA indicates nontranslated regions of 52-53 bases at the 5' end and 175 bases at the 3' end. The 5'-mRNA start site was located within a 12-nucleotide sequence which is conserved in all late hyperexpressed baculovirus genes.

Animals↗

[Restriction mapping of genome and nucleotide sequence of Aujeszky's disease virus strains isolated in CIS].

Auesku disease virus--suid herpesvirus type I (SHV-1) genome is analyzed by the restriction fragment pattern analysis. The analyzed strains isolated in CIS countries in 1962-1992 were compared with the European strains. Genomes of field strains Arsk, Turkmenia, and Geneva differed and even lacked the restriction fragments typical of vaccine strains MK-25 or UNIIEV-18S, which agrees with the results of the neutralization test. Immunobiological characteristics of SHV-1 strains are discussed.

Animals↗