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1.
Chiu CH Amemiya CT Carr JL Bhargava J Hwang JK Shashikant CS Ruddle FH Wagner GP 《Development genes and evolution》2000,210(2):105-109
The identification of cis-sequences responsible for spatiotemporal patterns of gene expression often requires the functional analysis of large genomic
regions. In this study a 100-kb zebrafish Hoxa-11b-lacZ reporter gene was constructed and expressed in transgenic mice. PAC clone 10-O19, containing a portion of the zebrafish HoxA-b
cluster, was captured into the yeast-bacterial shuttle vector, pPAC-ResQ, by recombinogenic targeting. A lacZ reporter gene was then inserted in-frame into exon 1 of the zfHoxa-11b locus by a second round of recombinogenic targeting. Expression of the zfHoxa-11b-lacZ reporter gene in 10.5 d.p.f. transgenic mouse embryos was observed only in the posterior portion of the A-P axis, in the paraxial mesoderm, neural tube,
and somites. These findings demonstrate the utility of recombinogenic targeting for the modification and expression of large
inserts captured from P1/PAC clones.
Received: 22 June 1999 / Accepted: 1 September 1999 相似文献
2.
T. Leroy A. -M. Henry M. Royer I. Altosaar R. Frutos D. Duris R. Philippe 《Plant cell reports》2000,19(4):382-385
A synthetic version of the cry1Ac gene of Bacillus thuringiensis has been used for the transformation of coffee species (Coffea canephora and C. arabica) to confer resistance to an important pest, the coffee leaf miner (Perileucoptera coffeella and other Leucoptera spp). Somatic embryos were co-cultivated with the LBA4404 strain of Agrobacterium tumefaciens containing the cry1Ac gene. More than 100 transformed plants from independent transformation events were obtained for each coffee genotype.
The integration and expression of the cry1Ac gene was studied, and effective resistance of transgenic plants against leaf miner was verified in bioassays with the
insects. These plants could represent a good opportunity to analyse the impact of genetic engineering of perennial crops for
sustainable resistance to an obligate endocarpic pest using a B. thuringiensis insecticidal protein.
Received: 7April 1999 / Revision received: 20 July 1999 / Accepted: 22 July 1999 相似文献
3.
Genomic structure, mapping, and expression analysis of the mammalian Lunatic, Manic, and Radical fringe genes 总被引:3,自引:0,他引:3
Jennifer L. Moran Stuart H. Johnston Cordelia Rauskolb Jayant Bhalerao Anne M. Bowcock Thomas F. Vogt 《Mammalian genome》1999,10(6):535-541
The three members of the mammalian fringe gene family, Manic fringe (Mfng), Radical fringe (Rfng), and Lunatic fringe (Lfng), were identified on the basis of their similarity to Drosophila fringe (fng) and their participation in the evolutionarily conserved Notch receptor signaling pathway. Fringe genes encode pioneer secretory
proteins with weak similarity to glycosyltransferases. Both expression patterns and functional studies support an important
role for Fringe genes in patterning during embryonic development and an association with cellular transformation. We have
now further characterized the expression and determined the chromosomal localization and genomic structure of the mouse Mfng, Rfng, and Lfng genes; the genomic structure and conceptual open reading frame of the human RFNG gene; and the refined chromosomal localization
of the three human fringe genes. The mouse Fringe genes are expressed in the embryo and in adult tissues. The mouse and human
Fringe family members map to three different chromosomes in regions of conserved synteny: Mfng maps to mouse Chr 15, and MFNG maps to human Chr 22q13.1 in the region of two cancer-associated loci; Lfng maps to mouse Chr 5, and LFNG maps to human Chr 7p22; Rfng maps to mouse Chr 11, and RFNG maps to human Chr 17q25 in the minimal region for a familial psoriasis susceptibility locus.
Characterization of the genomic loci of the Fringe gene family members reveals a conserved genomic organization of 8 exons.
Comparative analysis of mammalian Fringe genomic organization suggests that the first exon is evolutionarily labile and that
the Fringe genes have a genomic structure distinct from those of previously characterized glycosyltransferases.
Received: 19 February 1999 / Accepted: 22 February 1999 相似文献
4.
A homologue of the yeast HOP1 gene is inactivated in the Arabidopsis meiotic mutant asy1 总被引:5,自引:0,他引:5
Synapsis of homologous chromosomes is a key event in meiosis as it is essential for normal chromosome segregation and is implicated
in the regulation of crossover frequency. We have previously reported the identification and cytological characterisation
of a T-DNA-tagged asynaptic mutant of Arabidopsis thaliana. We have demonstrated that this mutant, asy1, is defective in meiosis in both males and females. Cloning and nucleotide sequencing of the ASY1 gene has revealed that it encodes a polypeptide of 596 amino acids that exhibits similarity to the HOP1 gene of Saccharomyces cerevisiae, which is known to encode a protein essential for synaptonemal complex assembly and normal synapsis. Expression studies indicate
that, in common with a number of other Arabidopsis meiotic genes, ASY1 exhibits low-level expression in a range of plant tissues. Southern analysis coupled with database searching has resulted
in the identification of an ASY1 homologue, ASY2. Although asy1 exhibits a strong asynaptic phenotype, a residual low level of synapsis indicates that ASY1 and ASY2 may exhibit a low degree of functional redundancy.
Received: 22 September 1999; in revised form: 18 October 1999 / Accepted: 18 October 1999 相似文献
5.
Fischer W Schwan D Gerland E Erlenfeld GE Odenbreit S Haas R 《Molecular & general genetics : MGG》1999,262(3):501-507
Helicobacter pylori produces a number of proteins associated with the outer membrane, including adhesins and the vacuolating cytotoxin. We observed
that the functional expression of such proteins is deleterious to Escherichia coli, the host bacterium used for gene cloning. Therefore, a general method was developed for the functional expression of such
genes on a shuttle vector in H. pylori, which has been termed SOMPES (Shuttle vector-based Outer Membrane Protein Expression System). The intact, active gene is
reconstituted by recombination in H. pylori from partial gene sequences cloned on an E. coli-H. pylori shuttle vector. This system was established in an H. pylori strain carrying a precise, unmarked chromosomal deletion of the vacA gene, which was constructed by adapting the streptomycin sensitivity system to H. pylori. It is based on the expression of the H. pylori rpsL gene as a counterselectable marker in the genetic background of an rpsL mutant. The utility of this approach is demonstrated by the expression of a recombinant gene encoding vacuolating cytotoxin
(vacA) and a recombinant gene encoding an adherence-associated outer membrane protein (alpA) in H. pylori.
Received: 10 May 1999 / Accepted: 7 July 1999 相似文献
6.
7.
An effective plant regeneration procedure and a gene transfer system via Agrobacterium tumefaciens were developed in Brassica campestris ssp. parachinensis. Hypocotyls from 5-day-old seedlings with 2 days pre-culture were infected with Agrobacterium strain MOG301 harboring a binary vector containing a synthetic Bacillus thuringiensis (B.t.) cry1Ab or cry1Ac gene with full codon-modification. After culture and selection on MS medium supplemented with 4.0 mg/l BAP, 2.0 mg/l NAA,
70 μM AgNO3 and 50 mg/l kanamycin, a number of kanamycin-resistant plantlets were regenerated. PCR and Southern blotting analysis were
used to identify and characterize the transgenic plants with the integrated cry1Ab or cry1Ac gene. Western blotting analysis of the transgenic plants confirmed the expression of insecticidal proteins encoded by cry1Ab or cry1Ac. Subsequent bioassay with larvae of the Diamondback moth, Plutella xylostella, demonstrated that the transgenic plants were resistant to feeding damage.
Received: 22 February 1999 / Revision received: 14 April 1999 / Accepted: 26 April 1999 相似文献
8.
Adam J.W. Paige Brent W. Kiernan Anabel Varela Michael J.C. Rogers David Hughes Karen P. Steel Steve D.M. Brown 《Mammalian genome》2000,11(1):51-57
Whirler (wi) mice display profound deafness and a head-tossing and circling phenotype, showing an autosomal recessive mode of inheritance.
The wi mutation has been shown to map close to the Orm gene cluster on mouse Chromosome (Chr) 4. We have, therefore, investigated the Orm loci as candidates for the whirler gene. Detailed mapping and analysis of the Orm gene cluster in both normal and whirler mice indicates the presence of a <48-kb deletion in whirler mice that disrupts the
Orm1 locus. The Orm1 locus is also deleted in the CE/J mouse strain, and we discuss the candidature of Orm1 for the whirler gene.
Received: 22 June 1999 / Accepted: 17 September 1999 相似文献
9.
A. V. Babwah C. S. Waddell 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(5):802-809
The enzyme cytosine deaminase, encoded by the codA gene, catalyzes the deamination of the non- toxic compound 5-fluorocytosine (5-FC) to the highly toxic compound 5-fluorouracil
(5-FU). Cytosine deaminase activity is not found in higher plants and Brassica napus seedlings are unaffected by the presence of 5-FC in the growth medium. In codA-transformed B. napus seedlings, expression of cytosine deaminase results in a reduction of root and hypocotyl lengths, and a severe suppression
of true leaf development. This phenotype is dependent on the presence of the 5-FC substrate and no effects are seen in plants
grown in the absence of the substrate or in sibling plants lacking the transgene. The codA transformants have been assessed over three generations of growth and in each generation the transgene is stably inherited
and confers the same 5-FC-sensitive phenotype. Transfer of 5-FC-sensitive seedlings to soil results in the restoration of
normal growth in up to 100% of the seedlings. These results indicate that codA is a versatile dominant marker gene that can be used effectively in B. napus for substrate-dependent negative selection.
Received: 24 June 1999 / Accepted: 22 July 1999 相似文献
10.
H. Fukuoka T. Ogawa I. Mitsuhara T. Iwai K. Isuzugawa Yoko Nishizawa Y. Gotoh Yaeko Nishizawa A. Tagiri M. Ugaki M. Ohshima H. Yano N. Murai Y. Niwa T. Hibi Y. Ohashi 《Plant cell reports》2000,19(8):815-820
The NCR promoter (PNCR) from soybean chlorotic mottle virus (SoyCMV) was used to express the selectable marker, neomycin
phosphotransferase (nptII) gene, in Agrobacterium-mediated transformation of both monocot (rice) and dicot (tobacco) plants. A multi-cloning site for insertion of a gene of
interest into the binary vector pTN is located proximal to the right border region of T-DNA. When chimeric genes under the
control of other strong promoters were located in a head-to-head orientation to the PNCR-nptII gene, kanamycin-resistant tobacco shoots were generated more efficiently than when using the original pTN vectors. This suggests
that the enhancer-like sequences in the promoters adjacent to PNCR may promote expression of the PNCR-nptII gene.
Received: 20 August 1999 / Revision received: 16 November 1999 / Accepted: 19 November 1999 相似文献
11.
We have identified a plant homologue of the Drosophila meiotic gene Pelota in Arabidopsis thaliana (AtPelota1). This gene maps to chromosome 4 of Ara- bidopsis and is one of two Pelota homologues present in this plant. When the expression pattern of AtPelota1 was examined it was found to be expressed at similar levels in all plant tissues tested (whole plant, bud, stem, leaf and
root). This expression pattern corresponds to that seen for some other Arabidopsis meiotic genes and their homologues. A search of the databases reveal that the AtPelota gene family is widespread with homologues present in higher and lower eukaryotes and archaebacteria, but not eubacteria.
Received: 13 December 1999 / Accepted: 27 December 1999 相似文献
12.
K. Rajasekaran J. W. Cary T.J. Jacks K. D. Stromberg T.E. Cleveland 《Plant cell reports》2000,19(4):333-338
Transgenic tobacco plants producing chloroperoxidase (CPO-P), encoded by a novel gene from Pseudomonas pyrrocinia, were obtained by Agrobacterium-mediated transformation. Successful transformation was shown by PCR, Southern, northern and western blot analyses, and assays
of CPO-P enzyme activity. Extracts from plants transformed with the CPO-P gene significantly reduced Aspergillus flavus colonies by up to 100% compared with extracts from control plants transformed with pBI121. Compared with controls, the transformed
plants showed increased disease resistance in planta against a fungal pathogen, Colletotrichum destructivum, the causal agent of tobacco anthracnose.
Received: 10 March 1999 / Revision received: 22 June 1999 · Accepted: 5 July 1999 相似文献
13.
Transformation and regeneration of garlic (Allium sativum L.) by Agrobacterium-mediated gene transfer 总被引:5,自引:0,他引:5
By using highly regenerative calluses, we developed a stable transformation system in garlic (Allium sativum L.). The temperature and number of days of co-cultivation with Agrobacterium tumefaciens was shown to be an important factor in transient expression of the uid A gene. After a culture period of 5 months in selection medium containing hygromycin, 20 shoots were induced from ca. 1000
calluses, among which 15 plants expressed β-glucuronidase activity upon staining with X-Gluc. Shoots developed into transgenic garlic after 1 month. Integration of the uid A gene was confirmed by Southern blot analysis for genomic DNA of transgenic garlic plants.
Received: 25 October 1999 / Revision received: 16 February 2000 / Accepted: 22 February 2000 相似文献
14.
A promoter vector pACPR33 for Escherichia coli based on the promotorless ampicillin-resistance gene from pBR322 has been constructed. The promoter of the ampicillin-resistance
gene was deleted and replaced by a suitable multiple cloning site. Molecular cloning of promoters into the polylinker resulted
in activation of the ampicillin resistance in E. coli. The plasmid contains a functional origin of DNA replication and a tetracycline resistance gene for E. coli, and a chloramphenicol resistance gene for S. aureus. The vector permitted direct detection of promoter activity, especially strong promoters, by easy iodometric determination
of β-lactamase activity in liquid or solid media.
Received: 26 July 1999 / Accepted: 22 November 1999 相似文献
15.
Allelic expression of IGF2 in marsupials and birds 总被引:12,自引:0,他引:12
Genomic imprinting, the parent-of-origin- specific expression of genes, has been observed in a variety of eutherian mammals.
One gene that has been shown to be imprinted in all eutherians examined is the IGF2 gene. This gene encodes a potent fetal-specific growth factor that is expressed almost exclusively from the paternal chromosome.
Several other imprinted genes in the IGF2 pathway are imprinted as well, suggesting that IGF2 is a focal point for the selective pressure leading to imprinted gene expression. This observation is in keeping with a proposal
that imprinting arose as the result of a genetic conflict between parents over the allocation of maternal resources to the
embryo. One prediction of this model is that imprinting exists in species in which there is at least some contribution of
maternal resources to the embryo, and in which polyandry is observed. To test this prediction the allelic expression of the
IGF2 gene was examined in two noneutherian species. The IGF2 gene was shown to be expressed in a paternal-specific manner identical to that in eutherians in Monodelphis domestica, a placental South American opossum. In contrast, the IGF2 gene is biallelic in expression in chickens, which are oviparous, and make no postfertilization contribution of maternal
resources to the offspring.
Received: 24 June 1999 / Accepted: 28 July 1999 相似文献
16.
J.-H. Sohn E.-S. Choi H. A. Kang J.-S. Rhee M. O. Agaphonov M. D. Ter-Avanesyan S.-K. Rhee 《Applied microbiology and biotechnology》1999,51(6):800-807
To facilitate the selection of multiple gene integrants in Hansenula polymorpha, a rapid and copy-number-controlled selection system was developed using a vector containing a telomeric autonomous replication
sequence and the bacterial aminoglycoside 3-phosphotransferase (APH) gene. Direct use of the unmodified APH gene as a dominant selectable marker resulted in the extremely slow growth of transformants and the frequent selection of
spontaneous resistance. For the proper performance of the APHgene, a set of deleted glyceraldehyde-3-phosphate dehydrogenase (GAPDH) promoters of H. polymorpha were fused to the APH gene. The fusion construct with the 578-bp GAPDH promoter conferred G418 resistance sufficient to allow rapid growth of transformants, and thus facilitated the selection
of transformants with up to 15 tandem copies of the vector. To increase further the integration copy number within the gene-dose-dependent
range, the GAPDHpromoter was serially deleted down to the −61 nucleotide. With this weak expression cassette, the integration copy number
could easily be controlled between 1 and 50. Tandemly integrated copies of plasmids near the end of the chromosome were mitotically
stable over l50 generations. The dosage-dependent selection system of this study would provide a powerful tool for the development
of H. polymorpha as an industrial strain to produce recombinant proteins.
Received: 23 October 1998 / Received revision: 6 January 1999 / Accepted: 22 January 1999 相似文献
17.
A novel mouse gene, associated with the enhancer-trap mutation TKZ736, has been cloned and sequenced. It encodes a polyspecific
transmembrane transporter with 12 putative transmembrane domains, that shares significant homology with the mouse organic
cation transporter 1 (Oct1/Slc22a1) called Lx1. Like Oct1/Slc22a1/Lx1, this gene maps to the proximal part of Chromosome (Chr) 17, but shows a different expression pattern from Oct1/Slc22a1/Lx1. The gene identified here is predominantly expressed in the kidney and ureter, but no expression is detectable in liver. Sequence
comparisons suggest that this novel gene most likely represents the mouse homolog of the rat organic cation transporter 2
gene. The genomic DNA flanking the 3′ transgene integration site in the enhancer-trap mutation TKZ736 encodes the second exon
of the Oct2/Slc22a2 gene.
Received: 6 July 1998 / Accepted: 15 October 1998 相似文献
18.
Emmanuel Collec Yves Colin Florence Carbonnet Claude Hattab Olivier Bertrand Jean Pierre Cartron C. Le Van Kim 《Immunogenetics》1999,50(1-2):16-21
The human Kx blood group antigen is carried by a 37 000 M
r apparent molecular mass membrane polypeptide which is deficient in rare individuals with the McLeod syndrome. The X-linked
human XK gene is transcribed in many tissues including adult skeletal muscle and brain, sieges of disorders observed in McLeod syndrome.
We report here the cloning of the orthologous mouse XK mRNA. Comparison of XK from human and mouse revealed 80% sequence similarity at the amino acid level. The mouse XK gene is organized in two exons and is expressed in many tissues, but its expression pattern is slightly different from that
of the human gene. The presence in mouse erythrocyte membrane of a 43 000 M
r Kx-related protein was demonstrated by immunoblotting with a rabbit antiserum directed against the human protein. With non-reduced
samples, a 140 000 M
r species was detected instead of the 43 000 M
r protein, suggesting that, as demonstrated in the Kx polypeptide might be complexed with another protein in mouse red cells,
presumably the homologue of the human Kell protein of 93 000 M
r.
Received: 22 February 1999 / Revised: 8 June 1999 相似文献
19.
20.
Elicitation of Arabidopsis thaliana (L.) Heynh. suspension cultures with the bacterial protein harpin (from Pseudomonas syringae pv. syringae) induced the activation of two kinases of 39 and 44 kDa, as demonstrated by in-gel kinase assays using myelin basic protein
(MBP) as a substrate. Both these kinases appeared to be tyrosine-phosphorylated upon activation, as demonstrated by treatment
with tyrosine phosphatase and immunoprecipitation using an anti-phosphotyrosine monoclonal antibody. An inhibitor of mammalian
mitogen-activated protein kinase (MAPK) activation, PD98059, inhibited harpin-induced MBPK activation, but did not inhibit
the activity of these kinases. PD98059 also inhibited harpin-induced programmed cell death and defence gene expression, suggesting
the involvement of harpin-induced MAPKs in defence responses in Arabidopsis thaliana.
Received: 23 February 1999 / Accepted: 22 July 1999 相似文献