Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Phage lambdacl+ gives clear plaques whereas phage lambdacIind- gives turbid plaques on a lawn of a mutant strain of E. coli K12. This strain, called STS, carries mutation spr in a tif sfi genetic background. I hypothesize that upon temperate phage infection, STS bacteria spontaneously inactivate phage repressor by the same mechanism involved in normal lysogenic induction which results in obligatory lytic growth of lambda+. The use of the STS mutant facilitates the isolation and genetic analysis of phage mutants with an abnormal response to lysogenic induction.
Mol Gen Genet 1976 May 07
PMID:A method for the isolation of phage mutants altered in their response ot lysogenic induction. 93 47

The relative order of 11 loci in the distal half of the short arm of the human X chromosome was examined using a panel of somatic cell hybrids containing structurally rearranged X chromosomes. The results show that the gene for phosphoribosylpyrophosphate synthetase 2 (PRPS2) is located between ZFX (zinc finger protein, X-linked) and STS (steroid sulfatase). The results also confirm the localization of ZFX distal to POLA (alpha-DNA polymerase). Previous studies have shown that STS and ZFX escape X-inactivation whereas POLA undergoes inactivation. Evaluation of PRPS2 expression in somatic cell hybrids containing inactive human X chromosomes showed that PRPS2 undergoes X-inactivation. These results provide further evidence for interspersion of loci that do and do not undergo X-inactivation on the human X chromosome.
Somat Cell Mol Genet 1992 Mar
PMID:Physical mapping of loci in the distal half of the short arm of the human X chromosome: implications for the spreading of X-chromosome inactivation. 131 58

Orthorhombic crystals of isolectin I (LOLI) from the seeds of Lathyrus ochrus were first obtained during the STS 29 space shuttle mission. Subsequently, isostructural crystals were also obtained in the laboratory. They belong to the space group P2(1)2(1)2, with cell dimensions a = 135.84 A, b = 63.12 A and c = 54.54 A with one functional entity, a dimer, in the asymmetric unit (Vm = 2.2 A3/Da). The three-dimensional structure of LOLI, which was solved by the molecular replacement method using a 3 A resolution model of pea lectin, has subsequently been refined by using crystallographic data between 8.0 A and 1.9 A resolution, coupled to molecular dynamics and energy minimization techniques. The conventional R-factor is 0.185 for Fo greater than 1 sigma(Fo). The final model includes 220 well-defined water molecules and has root-mean-square deviations from ideal bond distances and angles of 0.004 A and 3 degrees, respectively. Only slight conformation differences have been found between the two alpha beta monomers. The molecular structure of LOLI, the first to be determined from the genus Lathyrus, is very similar to those of concanavalin A, pea lectin and favin. Differences are confined to the loop regions and beta-chain termini. Comparison of equivalent C alpha atom positions between our final model and the pea lectin structure shows slight differences in the association of the two monomers, which are probably due to the different environments in the crystals. The root-mean-square deviation between C alpha atoms of LOLI and pea lectin is 0.40 A. The metal binding sites are very similar in pea lectin, concanavalin A and LOLI. The sugar-binding sites of LOLI are occupied by four well-ordered water molecules each. The cleavage site for one of the monomers is specially well defined in the final electron density map: the amino group of Glul (alpha) seems to form a salt bridge with the carboxylate group of the terminal Asn181 (beta). A detailed analysis of the difference in crystal packing contacts between pea lectin and LOLI shows that, as might be expected, several of the intermolecular interactions are mediated by residues that correspond to substitutions in the LOLI amino acid sequence.
J Mol Biol 1990 Jul 20
PMID:X-ray crystal structure determination and refinement at 1.9 A resolution of isolectin I from the seeds of Lathyrus ochrus. 238 Sep 88

The murine X-linked steroid sulfatase gene (Sts) normally escapes X inactivation. However, we have observed that most long-term murine cell cultures are deficient in STS activity even though only the L cells are known to be derived from an STS- mouse strain. To investigate this phenomenon, we developed a selective system whereby STS+ cells could be selected from STS- populations. The system is based on making cells dependent on cholesterol-sulfate as the sole source of cholesterol, allowing only STS+ cells to grow. Two STS- cell lines, after treatment with either 5-azacytidine (5AC) or ethyl methane sulfonate (EMS), yielded STS+ revertants, suggesting that their STS- phenotype was due to hypermethylation. To study the evolution of STS- cell lines, we established XO and XX primary lines from STS+ strains; the XX cell line remained STS+ after more than 200 cell doublings whereas the XO became STS- after about 100 doublings. Treatment of this STS- XO cell line with 5AC produced clones with restored STS activity. All the revertants showed a growth disadvantage compared to their STS- counterparts. It would appear that aberrant methylation is the basis for much of the STS deficiency observed in established murine lines and that its propagation is due to the growth advantage of STS- over STS+ cells.
Somat Cell Mol Genet 1988 Mar
PMID:Inactivation and reactivation of sex-linked steroid sulfatase gene in murine cell culture. 245 Apr 5

The objective of this study was to characterize the leaf rust resistance locus Lr1 in wheat. Restriction fragment length polymorphism (RFLP) analysis was performed on the resistant line Lr1/6* Thatcher and the susceptible varieties Thatcher and Frisal, as well as on the segregating F2 populations. Seventeen out of 37 RFLP probes mapping to group 5 chromosomes showed polymorphism between Lr1/6* Thatcher and Frisal, whereas 11 probes were polymorphic between the near-isogenic lines (NILs) Lr1/6* Thatcher and Thatcher. Three of these probes were linked to the resistance gene in the segregating F2 populations. One probe (pTAG621) showed very tight linkage to Lr1 and mapped to a single-copy region on chromosome 5D. The map location of pTAG621 at the end of the long arm of chromosome 5D was confirmed by the absence of the band in the nulli-tetrasomic line N5DT5B of Chinese Spring and a set of deletion lines of Chinese Spring lacking the distal part of 5DL. Twenty-seven breeding lines containing the Lr1 resistance gene in different genetic backgrounds showed the same band as Lr1/6* Thatcher when hybridized with pTAG621. The RFLP marker was converted to a sequence-tagged-site marker using polymerase chain reaction (PCR) amplification. Sequencing of the specific fragment amplified from both NILs revealed point mutations as well as small insertion/deletion events. These were used to design primers that allowed amplification of a specific product only from the resistant line Lr1/6* Thatcher. This STS, specific for the Lr1 resistance gene, will allow efficient selection for the disease resistance gene in wheat breeding programmes. In addition, the identification of a D-genome-specific probe tightly linked to Lr1 should ultimately provide the basis for positional cloning of the gene.
Mol Gen Genet 1995 Sep 20
PMID:Genetic and physical characterization of the LR1 leaf rust resistance locus in wheat (Triticum aestivum L.). 747 55

Synthesis of oestrogens within breast tissues makes an important contribution to the high concentrations of oestradiol which are found in breast tumours. The activities of the enzymes involved in oestrogen synthesis, i.e. the aromatase, oestradiol dehydrogenase (E2DH) and oestrone sulphatase (E1-STS), can be stimulated by several growth factors and cytokines. As it is possible that some of these factors may be derived from cells of the immune system (macrophages and lymphocytes), the effects of basic fibroblast growth factor (bFGF) and interleukin-2 (IL-2), which are produced by these cells, on E2DH activity was examined in MCF-7 cells. Treatment of these cells with bFGF resulted in a dose-dependent increase in E2DH reductive activity whereas IL-2 was inactive at the concentration tested. To obtain further evidence that factors produced by macrophages and lymphocytes can modulate the activities of enzymes involved in oestrogen synthesis, conditioned medium was collected from these cells and found to stimulate both E1-STS and E2DH activities. In addition to understanding the control of oestrogen synthesis in breast tumours an inhibitor to block the synthesis of oestrone via the oestrone sulphatase pathway was developed. Oestrone-3-O-sulphamate (EMATE) is a potent, irreversible, inhibitor of E1-STS. A single dose of EMATE (10 mg/kg) inhibited tissue E1-STS activity in rats by more than 95% for up to 7 days, indicating that this compound may have considerable therapeutic potential for the treatment of breast cancer. Evidence is also reviewed that another steroid sulphatase, dehydroepiandrosterone sulphate sulphatase, may have a crucial role in regulating cytokine production and that this may indirectly control tumour oestrogen synthesis.
J Steroid Biochem Mol Biol 1995 Jun
PMID:The role of cytokines and sulphatase inhibitors in regulating oestrogen synthesis in breast tumours. 762 90

In order to study the distribution of genes that escape X chromosome inactivation, a high density yeast artificial chromosome (YAC) contig and STS map spanning approximately 6 Mb has been constructed in Xp11.21-p11.22. The contig contains 113 YACs mapped with 53 markers, including 10 genes. Four genes have been assayed for their expression status on both the active and inactive human X chromosomes, and these data have been combined with previous results on two other genes in the contig. Three of these genes escape X inactivation and have been localized to a single YAC clone of approximately 1075 kb. The other three genes are subject to inactivation, with two of them lying among the genes that escape inactivation. These results suggest that there are both regional control signals as well as gene-specific elements that determine the X inactivation status of genes on the proximal short arm of the human X chromosome.
Hum Mol Genet 1995 Apr
PMID:Three genes that escape X chromosome inactivation are clustered within a 6 Mb YAC contig and STS map in Xp11.21-p11.22. 763 24

Three Mus musculus DBA/2 YAC libraries were constructed using a half-YAC telomere cloning vector. This functional complementation approach yields libraries which include terminal restriction fragments of the mouse genome. Screening all three libraries led to the isolation of 32 independent clones which carry linear YACs containing the mouse terminal repeat sequence, (TTAGGG)n. These YACs provide a resource to isolate regions of the mouse genome close to chromosome termini and excluded from existing conventional YAC libraries. To demonstrate their utility, a hybridization probe was isolated from Mtel-1, the first (TTAGGG)n-containing YAC isolated. This probe detects a approximately 70 kb Kpnl fragment in the mouse genome which is sensitive to pretreatment with BAL31 exonuclease. A PCR-based genetic marker generated from the sequence of this probe maps 4.4 cM from the most distal anchor locus on chromosome 10 in the EUCIB interspecific backcross. STS primers for this locus, D10Hgu1, were used to isolate YAC 110F4 from a commercially available mouse YAC library. Fluorescence in situ hybridization demonstrates that YAC 110F4 hybridizes to the distal telomere of chromosome 10. Clones in this collection of telomere YACs therefore partially overlap clones in conventional YAC libraries, and thus the previously unavailable terminal regions of the mouse genome can now be linked with the developing mouse STS YAC contig. Genetic markers such as D10Hgu1 allow the ends of the mouse genetic map to be defined, thus closing the map.
Hum Mol Genet 1995 Jun
PMID:YAC cloning Mus musculus telomeric DNA: physical, genetic, in situ and STS markers for the distal telomere of chromosome 10. 765 54

Detailed physical maps of the human genome are important resources for the identification and isolation of disease genes and for studying the structure and function of the genome. We used data from STS content mapping of YACs and natural and induced chromosomal breakpoints to anchor contigs of overlapping yeast artificial chromosome (YAC) clones spanning extensive regions of human chromosome 22. The STSs were assigned to specific regions (bins) on the chromosome using cell lines from a somatic hybrid mapping panel defining a maximum of 25 intervals. YAC libraries were screened by PCR amplification of hierarchical pools of yeast DNA with 238 markers, and a total of 587 YAC clones were identified. These YACs were assembled into contigs based upon their shared STS content using a simulated annealing algorithm. Fifteen contigs, containing between 2 and 74 STSs were assembled, and ordered along the chromosome based upon the cytogenetic breakpoint, meiotic and PFG maps. Additional singleton YACs were assigned to unique chromosomal bins. These ordered YAC contigs will be useful for identifying disease genes and chromosomal breakpoints by positional cloning and will provide the foundation for higher resolution physical maps for large scale sequencing of the chromosome.
Hum Mol Genet 1995 Jan
PMID:Integration of physical, breakpoint and genetic maps of chromosome 22. Localization of 587 yeast artificial chromosomes with 238 mapped markers. 771 35

Physical mapping of the human genome appears to be a complicated problem for the molecular genetics of higher organisms. The difficulties are not only due to the great amount of work to be done, but mostly due to the peculiarities of genome organization (repeated nucleotide sequences, non-clonable, methylated and toxic fragments, etc.). Mapping procedures based on molecular hybridization do not allow to obtain the unambiguous results due to the occurrence of the repeats of different types common for the genome as a whole. Giant DNA fragments (e.g. YAC--Yeast Artificial Chromosomes) undergo deletions, transformations and chimerism and cannot be the main approach for genome mapping. The new strategy for genome mapping is described with reference to the human chromosome 3--one of the largest human chromosomes. The main steps of this new strategy are the following: 1) sequencing of STS (Sequence Tagged Sites) flanking DNA rare-cutting restriction sites; 2) alignment of the STS along the chromosomal DNA (generation of the contigs) based on the comparative computer analysis of STS from the same and from the neighboring restriction sites, 3) determination of the distance between STS by hybridization of large DNA fragments with STS. In order to apply this strategy called "shot-gun sequencing strategy for long range genome mapping" a new family of vectors (SK series) specially designed for the genome cloning was constructed and the simplified inexpensive technology for preparing the jumping/linking libraries was developed. Chromosome 3 fragments were sequenced around NotI sites, and the contigs covering about 50 Mbp of genomic DNA were constructed. The perspectives for the whole human genome mapping are discussed.
Mol Biol (Mosk)
PMID:[Physical mapping of the human genome: on the way to developing an optimal strategy]. 788 25


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