共查询到20条相似文献,搜索用时 31 毫秒
1.
S. A. Forbes A. A. J. Pannett J. H. D. Bassett B. Harding C. Wooding R. V. Thakker R. Butler D. Ogilvie R. Anand P. Gaudray G. Weber C. Larsson C. X. Zhang A. Calender J. W. M. Höppener C. J. M. Lips K. Kas 《Human genetics》1997,100(3-4):481-485
The multiple endocrine neoplasia type 1 (MEN1) locus has been previously localised to 11q13 by combined tumour deletion mapping
and recombination studies, and a 0.5-Mb region, flanked by PYGM and D11S449, has been defined. In the course of constructing
a contig, we have identified the location of the gene encoding the B56β subunit of protein phosphatase 2A (PP2A), which is
involved in cell signal transduction pathways and thus represents a candidate gene for MEN1. We have searched for mutations
in the PP2A-B56β coding region, together with the 5′ and 3′ untranslated regions in six MEN1 patients. DNA sequence abnormalities
were not identified and thus the PP2A-B56β gene is excluded as the candidate gene for MEN1. However, our precise localisation
of PP2A-B56β to this region of 11q13 may help in elucidating the basis for other disease genes mapping to this gene-rich region.
Received: 17 April 1997 / Accepted: 22 April 1997 相似文献
2.
Bruno Reyntjens David R. Jollie Philip J. Stephens H. Samantha Gao-Sheridan B. K. Burgess 《Journal of biological inorganic chemistry》1997,2(5):595-602
Ferredoxins that contain 2[4Fe-4S]2+/+ clusters can be divided into two classes. The "clostridial-type" ferredoxins have two CysXXCysXXCysXXXCysPro motifs. The
"photosynthetic bacterial and nif-related" ferredoxins have one motif of that type and one more unusual CysXXCysX7–9CysXXXCysPro motif. In Azotobacter vinelandii three gene sequences have been reported that contain the latter motif, but until now none of the gene products has been purified.
Here we report the purification of a small anionic [Fe-S] protein with yields of ∼3 mg per 500 g cell paste. NH2-terminal sequence analysis shows that this protein is the product of a previously sequenced A. vinelandii gene that is found upstream of fixA and is cotranscribed with fixABCX. That gene was originally named fixP, but since that gene designation is now commonly used for a very different cb-type cytochrome oxidase we have renamed the
gene fixFd and its product Fix Fd. Its sequence places Fix Fd in the class of "photosynthetic bacterial and nif-related" 2[4Fe-4S]2+/1+ ferredoxins that includes Chromatium vinosum ferredoxin. Studies of the purified protein by Fe analysis, absorption, CD and EPR spectroscopies and electrochemistry confirm
this characterization; the reduction potentials of the two clusters are –440 mV vs SHE. The fact that A. vinelandii synthesizes three different proteins with the same sequence motif, each of which is likely to have a different function,
shows that although sequence motifs may be used reliably to classify ferredoxins by cluster type they cannot yet be used reliably
for classifying ferredoxins by function.
Received: 31 January 1997 / Accepted: 9 June 1997 相似文献
3.
Stefan Rieder Sead Taourit Denis Mariat Bertrand Langlois Gérard Guérin 《Mammalian genome》2001,12(6):450-455
Coat color genetics, when successfully adapted and applied to different mammalian species, provides a good demonstration
of the powerful concept of comparative genetics. Using cross-species techniques, we have cloned, sequenced, and characterized
equine melanocortin-1-receptor (MC1R) and agouti-signaling-protein (ASIP), and completed a partial sequence of tyrosinase-related protein 1 (TYRP1).
The coding sequences and parts of the flanking regions of those genes were systematically analyzed in 40 horses and mutations
typed in a total of 120 horses. Our panel represented 22 different horse breeds, including 11 different coat colors of Equus caballus. The comparison of a 1721-bp genomic fragment of MC1R among the 11 coat color phenotypes revealed no sequence difference apart from the known chestnut allele (C901T). In particular,
no dominant black (E
D) mutation was found.
In a 4994-bp genomic fragment covering the three putative exons, two introns and parts of the 5′- and 3′-UTRs of ASIP, two intronic base substitutions (SNP-A845G and C2374A), a point mutation in the 3′-UTRs (A4734G), and an 11-bp deletion in
exon 2 (ADEx2) were detected. The deletion was found to be homozygous and completely associated with horse recessive black
coat color (A
a
/A
a
) in 24 black horses out of 9 different breeds from our panel. The frameshift initiated by ADEx2 is believed to alter the
regular coding sequence, acting as a loss-of-function ASIP mutation. In TYRP1 a base substitution was detected in exon 2 (C189T), causing a threonine to methionine change of yet unknown function, and
an SNP (A1188G) was found in intron 2.
Received: 22 November 2000 / Accepted: 07 February 2001 相似文献
4.
M. Okubo Asako Horinishi Norimasa Nakamura Yoshiko Aoyama Masaji Hashimoto Yuzo Endo Toshio Murase 《Human genetics》1998,102(1):1-5
Genetic deficiency of the glycogen-debranching enzyme (debrancher) causes glycogen storage disease type III (GSD III), which
is divided into two subtypes: IIIa and IIIb. In GSD IIIb, glycogen accumulates only in the liver, whereas both liver and muscles
are involved in GSD IIIa. The molecular basis for the differences between the two subtypes has not been fully elucidated.
Recently, mutations in exon 3 of the debrancher gene were reported to be specifically associated with GSD IIIb. However, we
describe a homozygous GSD IIIb patient without mutations in exon 3. Analysis of the patient’s debrancher cDNA revealed an
11-bp insertion in the normal sequence. An A to G transition at position –12 upstream of the 3′ splice site of intron 32 (IVS
32 A–12→G) was identified in the patient’s debrancher gene. No mutations were found in exon 3. Mutational analysis of the family
showed the patient to be homozygous for this novel mutation as well as three polymorphic markers. Furthermore, the mother
was heterozygous and the parents were first cousins. The acceptor splice site mutation created a new 3′ splice site and resulted
in insertion of an 11-bp intron sequence between exon 32 and exon 33 in the patient’s debrancher mRNA. The predicted mutant
enzyme was truncated by 112 amino acids as a result of premature termination. These findings suggested that a novel IVS 32
A–12→G mutation caused GSD IIIb in this patient.
Received: 1 August 1997 / Accepted: 22 September 1997 相似文献
5.
Masahiko Yamamoto Takeshi Yasuda Kiyoshi Hayasaka A. Ohnishi Hiroo Yoshikawa Takehiko Yanagihara Tohru Ikegami Tatsunori Yamamoto Hirofumi Ohashi Tomoya Nishimura Terunori Mitsuma Hidenori Kiyosawa Phillip F. Chance G. Sobue 《Human genetics》1997,100(2):151-154
We have used human β2 and β4 cDNA probes to map the genes encoding two isoforms of the regulatory β subunit of voltage-activated
Ca2+ channels, viz. CACNB2 (β2) and CACNB4 (β4), to human chromosomes 10p12 and 2q22-q23, respectively, by fluorescence in situ
hybridization. The gene encoding the β2 protein, first described as a Lambert-Eaton myasthenic syndrome (LEMS) antigen in
humans, is found close to a region that undergoes chromosome rearrangements in small cell lung cancer, which occurs in association
with LEMS. CACNB2 (β2) and CACNB4 (β4) genes are members of the ion-channel gene superfamily and it should now be possible
to examine their loci by linkage analysis of ion-channel-related disorders. To date, no such disease-related gene has been
assigned to 10p12 and 2q22-q23.
Received: 5 February 1997 / Accepted: 4 April 1997 相似文献
6.
7.
To study the evolution of human X-linked red and green opsin genes, genomic sequences in large regions of the two genes were
compared. The divergences in introns 3, 4, and 5 and the 3′ flanking sequence of the two genes are significantly lower than
those in exons 4 and 5. The homogenization mechanism of introns and the 3′ flanking sequence of human red and green opsin
genes is probably gene conversion, which also occurred in exons 1 and 6. At least one gene conversion event occurred in each
of three regions (1, 3, and 5) in the sequences compared. In conclusion, gene conversion has occurred frequently between human
red and green opsin genes, but exons 2, 3, 4, and 5 have been maintained distinct between the two genes by natural selection.
Received: 29 September 1997 / Accepted: 29 September 1997 相似文献
8.
Y. Hisatomi K. Hanada S. Iida 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(7):1049-1056
Transposable elements have often been discovered as new insertion sequences in known genes, and minisatellites are often
employed as molecular markers in diagnostic and mapping studies. We compared the genes for flower pigmentation in a line of
the common morning glory bearing fully colored flowers with those in two anthocyanin
flaked
mutable lines producing variegated flowers and found RFLPs at the region of the ANS gene for anthocyanin biosynthesis. The DNA rearrangements detected by the RFLPs are due to integration of a novel type of
minisatellite, MiniSip1, having a long LTR retrotransposon, RTip1, inserted in the mutable lines. The structural analysis of the rearranged region revealed that the 12.4-kb RTip1 element is flanked by 5-bp target duplications within the MiniSip1 sequence and contains two LTR sequences of about 590 bp, a primer binding site for tRNALys, a typical polypurine tract and another new type of minisatellite, MiniSip2. Since no long open reading frame corresponding to the gag and pol genes was found, RTip1 appears to be a defective Ty3/gypsy-like element. Interestingly, the 269-bp-long MiniSip1 element comprises two alternating motifs of 41 bp and 19 bp, whereas the 962 bp long MiniSip2 element consists of two partially alternating motifs of 86 bp and 90 bp which are partially homologous to each other. Possible
evolutionary processes that may have generated the rearranged structure at the ANS gene region are also discussed.
Received: 25 April 1997 / Accepted: 16 May 1997 相似文献
9.
In a study of the 5′-flanking sequence of the Zea mays L. (maize) Glb1 gene in vitro, serial promoter deletions were generated and linked with the β-glucuronidase (GUS) reporter gene. The promoter deletion-GUS fusions were introduced into the maize P3377 cell line by particle
bombardment. GUS assays indicated that treatment of the maize cultured cells with abscisic acid (ABA) was required for Glb1-driven GUS transient expression, and that the –272-bp sequence of the Glb1 promoter was sufficient for ABA-regulated expression of GUS. The longest undeleted sequence used, –1391 GUS, showed relatively
low expression which could be indicative of an upstream silencer element in the Glb1 promoter between –1391 and –805. Further studies show that the Glb1-driven GUS activity of bombarded maize P3377 cells increases with increasing ABA concentration (up to 100–300 μm). Site-directed mutagenesis of a putative ABA response element, Em1a, abolished GUS expression in P3377 cells. This observation
indicated that the Em1a sequence in the Glb1 5′ regulatory region is responsible for the positive ABA regulation of gene expression.
Received: 9 May 1997 / Revision received: 9 November 1997 / Accepted: 8 December 1997 相似文献
10.
Human tRNA-specific adenosine deaminase (hADAT1) specifically converts A37 in the anticodon loop of human tRNAAla to inosine via a hydrolytic deamination mechanism. The enzyme is related to a family of RNA editing enzymes (ADARs) specific
for pre-mRNA, and it has been cloned based on its sequence homology to the catalytic domain of ADARs. In the present study
we have analyzed the 5′-flanking sequence of the murine ADAT1 gene, revealing that the first transcribed exon is located 1.1
kb downstream from the polyadenylation site of lysyl tRNA synthetase (KARS). The close proximity is conserved in the human
genome with an intergenic distance of 5.5 kb. We determined the complete cDNA sequence as well as exon/intron organization
of murine KARS. Significant sequence similarities between KARS and ADAT1 are apparent within their substrate interaction domains.
Radiation hybrid panel analysis mapped human ADAT1 and human KARS to region q22.2–22.3 of Chromosome (Chr) 16 with alanyl
tRNA synthetase (AARS) positioned centromeric to the KARS and ADAT1 genes. 16q22–24 has recently been recognized as a susceptibility
candidate locus for several autoimmune inflammatory diseases. The clustering of three tRNA specific genes, of which two are
specific for tRNAAla, may indicate their evolutionary relatedness or common factors involved in regulating their expression.
Received: 1 November 2000 / Accepted: 18 December 2000 相似文献
11.
N. Kitamoto J. Matsui Y. Kawai A. Kato S. Yoshino K. Ohmiya N. Tsukagoshi 《Applied microbiology and biotechnology》1998,50(1):85-92
For the development of an efficient gene expression system in a shoyu koji mold Aspergillus oryzae KBN616, the TEF1 gene, encoding translation-elongation factor 1α, was cloned from the same strain and used for expression of polygalacturonase
genes. The TEF1 gene comprised 1647 bp with three introns. The TEF1-α protein consisted of 460 amino acids possessing high identity to other
fungal TEF proteins. Two nucleotide sequences homologous to the upstream activation sequence, characterized for the ribosomal
protein genes in Saccharomyces cerevisiae, as well as the pyrimidine-rich sequences were present in the TEF1 gene promoter region, suggesting that the A. oryzae TEF1 gene has a strong promoter activity. Two expression vectors, pTFGA300 and pTFGB200 for production of polygalacturonases A
and B respectively, were constructed by using the TEF1 gene promoter. A polygalacturonase (PGB) gene cloned from the same strain comprised 1226 bp with two introns and encoded
a protein of 367 amino acids with high similarity to other fungal polygalacturonases. PGA and PGB were secreted at approximately
100 mg/l in glucose medium and purified to homogeneity. PGA had a molecular mass of 41 kDa, a pH optimum of 5.0 and temperature
optimum of 45 °C. PGB had a molecular mass of 39 kDa, a pH optimum of 5.0 and temperature optimum of 55 °C.
Received: 28 November 1997 / Received revision: 24 February 1998 / Accepted: 6 March 1998 相似文献
12.
The Protein Kinase C family of enzymes is a group of serine/threonine kinases that play central roles in cell-cycle regulation,
development and cancer. A key step in the activation of PKC is translocation to membranes and binding of membrane-associated
activators including diacylglycerol (DAG). Interaction of novel and conventional isotypes of PKC with DAG and phorbol esters
occurs through the two C1 regulatory domains (C1A and C1B), which exhibit distinct ligand binding selectivity that likely
controls enzyme activation by different co-activators. PKC has also been implicated in physiological responses to alcohol
consumption and it has been proposed that PKCα (Slater et al. J Biol Chem 272(10):6167–6173, 1997; Slater et al. Biochemistry 43(23):7601–7609, 2004), PKCε (Das et al. Biochem J 421(3):405–413, 2009) and PKCδ (Das et al. J Biol Chem 279(36):37964–37972, 2004; Das et al. Protein Sci 15(9):2107–2119, 2006) contain specific alcohol-binding sites in their C1 domains. We are interested in understanding how ethanol affects signal
transduction processes through its affects on the structure and function of the C1 domains of PKC. Here we present the 1H, 15N and 13C NMR chemical shift assignments for the Rattus norvegicus PKCδ C1A and C1B proteins. 相似文献
13.
Tarasova MV Kuznetsov VV Netesova NA Gonchar DA Degtyarev SKh 《Biochemistry. Biokhimii?a》2010,75(12):1484-1490
A restriction-modification system from Bacillus psychrodurans AC (recognition sequence 5′-CCGC-3′) comprises two DNA methyltransferases: M1.BspACI and M2.BspACI. The bspACIM1 gene was cloned in the pJW2 vector and expressed in Escherichia coli cells. High-purity M1.BspACI preparation has been obtained by chromatography on different carriers. M1.BspACI has a temperature
optimum of 30°C and demonstrates maximum activity at pH 8.0. M1.BspACI modifies the first cytosine in the recognition sequence
5′-CCGC-3′. The kinetic parameters of M1.BspACI DNA methylation are as follows: K
m for phage λ DNA is 0.053 μM and K
m for S-adenosyl-L-methionine is 5.1 μM. The catalytic constant (k
cat) is 0.095 min−1. 相似文献
14.
Heath Cole Knight Thomas R. Reynolds Gregory A. Meyers Robert J. Pomponio Gregory A. Buck Barry Wolf 《Mammalian genome》1998,9(4):327-330
Biotinidase cleaves biotin from biocytin, thereby recycling the vitamin. We have determined the structure of the human biotinidase
gene. A genomic clone, containing three exons that code for the mature enzyme, was obtained by screening a human genomic bacteriophage
library with the biotinidase cDNA by plaque hybridization. To obtain a clone containing the most 5′ exon of the biotinidase
cDNA, a human PAC library by PCR was screened. The human biotinidase gene is organized into four exons and spans at least
23 kb. The 5′-flanking region of exon 1 contains a CCAAT element, three initiator sequences, an octamer sequence, three methylation
consensus sites, two GC boxes, and one HNF-5 site, but has no TATA element. The region from nt −600 to +400 has features of
a CpG island and resembles a housekeeping gene promoter. The structure and sequence of this gene are useful for identifying
and characterizing mutations that cause biotinidase deficiency.
Received: 30 September 1997 / Accepted: 5 December 1997 相似文献
15.
Classical genetic studies in European rabbits (Oryctolagus cuniculus) suggested the presence of two alleles at the brown coat colour locus: a wild‐type B allele that gives dense black pigment throughout the coat and a recessive b allele that in the homozygous condition (b/b genotype) produces brown rabbits that are unable to develop black pigmentation. In several other species, this locus is determined by mutations in the tyrosinase‐related protein 1 (TYRP1) gene, encoding a melanocyte enzyme needed for the production of dark eumelanin. In this study, we investigated the rabbit TYRP1 gene as a strong candidate for the rabbit brown coat colour locus. A total of 3846 bp of the TYRP1 gene were sequenced in eight rabbits of different breeds and identified 23 single nucleotide polymorphisms (SNPs; 12 in intronic regions, five in exons and six in the 3′‐untranslated region) and an insertion/deletion of 13 bp, in the 3′‐untranslated region, organised in a few haplotypes. A mutation in exon 2 (g.41360196G>A) leads to a premature stop codon at position 190 of the deduced amino acid sequence (p.Trp190ter). Therefore, translation predicts a truncated TYRP1 protein lacking almost completely the tyrosinase domain. Genotyping 203 rabbits of 32 different breeds identified this mutation only in brown Havana rabbits. Its potential functional relevance in disrupting the TYRP1 protein and its presence only in brown animals strongly argue for this non‐sense mutation being a causative mutation for the recessive b allele at the brown locus in Oryctolagus cuniculus. 相似文献
16.
The brown coat colour of Coppernecked goats is associated with a non‐synonymous variant at the TYRP1 locus on chromosome 8 下载免费PDF全文
The recent development of a goat SNP genotyping microarray enables genome‐wide association studies in this important livestock species. We investigated the genetic basis of the black and brown coat colour in Valais Blacknecked and Coppernecked goats. A genome‐wide association analysis using goat SNP50 BeadChip genotypes of 22 cases and 23 controls allowed us to map the locus for the brown coat colour to goat chromosome 8. The TYRP1 gene is located within the associated chromosomal region, and TYRP1 variants cause similar coat colour phenotypes in different species. We thus considered TYRP1 as a strong positional and functional candidate. We resequenced the caprine TYRP1 gene by Sanger and Illumina sequencing and identified two non‐synonymous variants, p.Ile478Thr and p.Gly496Asp, that might have a functional impact on the TYRP1 protein. However, based on the obtained pedigree and genotype data, the brown coat colour in these goats is not due to a single recessive loss‐of‐function allele. Surprisingly, the genotype distribution and the pedigree data suggest that the 496Asp allele might possibly act in a dominant manner. The 496Asp allele was present in 77 of 81 investigated Coppernecked goats and did not occur in black goats. This strongly suggests heterogeneity underlying the brown coat colour in Coppernecked goats. Functional experiments or targeted matings will be required to verify the unexpected preliminary findings. 相似文献
17.
C. Daniells Magitha Maheshwar Lazarus Lazarou Felicity Davies Gerry Coles David Ravine 《Human genetics》1998,102(2):216-220
A search has been conducted for disease-causing mutations in the PKD1 gene in 147 unrelated ADPKD index cases. Using the polymerase chain reaction with primer pairs located in the 3′ single copy
region of the gene and single-strand conformation polymorphism analysis, we detected novel aberrant bands in five individuals
that were absent in 100 control samples. Sequencing revealed three nonsense mutations (Q4010X, E4024X, Q4041X), a frameshift
mutation (12262 del 2 bp), and a missense mutation (G4031D). In addition, three polymorphisms were detected [12346 + 19delG,
heterozygosity (0.13), I4044V (0.23), 12212-34C > A (0.07)]. The mutational mechanism for the recurrent mutation (Q4041X)
is likely to be slipped mispairing of an adjacent direct imperfect repeat sequence.
Received: 5 April 1997 / Accepted: 26 August 1997 相似文献
18.
《Molecular & general genetics : MGG》1997,256(2):195-202
A transposable element has been isolated from the entomopathogenic fungus Beauveria bassiana by trapping it in the nitrate reductase structural gene, which has been cloned from this species. The element had inserted
in the first exon of the nia gene and appeared to have duplicated the sequence TA at the site of insertion. It was 3336 bp long with 30-bp imperfect, inverted,
terminal repeats. The element, called hupfer, contained an open reading frame encoding a 321-amino acid protein similar to the IS630- or mariner-Tc1-like transposases, and a residual sequence of about 2 kb which was not significantly similar to any published sequence. There
are fewer than five copies of this transposable element present per genome in the fungus.
Received: 12 February 1997 / Accepted: 2 May 1997 相似文献
19.
A xylose reductase gene (xyl1) of Candida guilliermondii ATCC 20118 was cloned and characterized. The open reading frame of xyl1 contained 954 nucleotides encoding a protein of 317 amino acids with a predicted molecular mass of 36 kDa. The derived amino
acid sequence of C. guilliermondii xylose reductase was 70.4% homologous to that of Pichia stipitis. The gene was placed under the control of an alcohol oxidase promoter (AOX1) and integrated into the genome of a methylotrophic yeast, Pichia pastoris. Methanol induced the expression of the 36-kDa xylose reductase in both intracellular and secreted expression systems. The
expressed enzyme preferentially utilized NADPH as a cofactor and was functional both in vitro and in vivo. The different cofactor
specificity between P. pastoris and C. guilliermondii xylose reductases might be due to the difference in the numbers of histidine residues and their locations between the two
proteins. The recombinant was able to ferment xylose, and the maximum xylitol accumulation (7.8 g/l) was observed when the
organism was grown under aerobic conditions.
Received: 26 August 1997 / Received revision: 6 November 1997 / Accepted: 21 November 1997 相似文献
20.
Conservation in wheat high-molecular-weight glutenin gene promoter sequences: comparisons among loci and among alleles of the GLU-B1-1 locus 总被引:2,自引:0,他引:2
O. D. Anderson F. A. Abraham-Pierce A. Tam 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(5):568-576
The high-molecular-weight glutenin (HMW) genes and encoded subunits are known to be critical for wheat quality characteristics
and are among the best-studied cereal research subjects. Two lines of experiments were undertaken to further understand the
structure and high expression levels of the HMW-glutenin gene promoters. Cross hybridizations of clones of the paralogous
x-type and y-type HMW-glutenin genes to a complete set of six genes from a single cultivar showed that each type hybridizes
best within that type. The extent of hybridization was relatively restricted to the coding and immediate flanking DNA sequences.
Additional DNA sequences were determined for four published members of the HMW-glutenin gene family (encoding subunits Ax2*, Bx7, Dx5, and Dy10) and showed that the flanking DNA of the examined genes diverge at approximately −1200 bp 5′ to the start
codon and 200–400 bp 3′ to the stop codon. These divergence sites may indicate the boundaries of sequences important in gene
expression. In addition, promoter sequences were determined for alleles of the Bx gene (Glu-B1-1), a gene reported to show higher levels of expression than other HMW-glutenin genes and with variation among cultivars. The
sequences of Bx promoters from three cultivars and one wild tetraploid wheat indicated that all Bx alleles had few differences
and contained a duplicated portion of the promoter sequence “cereal-box” previously suspected as a factor in higher levels
of expression. Thus, the “cereal-box” duplication preceeded the origin of hexaploid wheat, and provides no evidence to explain
the variations in Bx subunit synthesis levels. One active Bx allele contained a 185-bp insertion that evidently resulted from
a transposition event.
Received: 5 August 1997 / Accepted: 6 November 1997 相似文献