共查询到20条相似文献,搜索用时 46 毫秒
1.
Nassima Fodil Laurent Laloux Valérie Wanner Philippe Pellet Georges Hauptmann Nobuhisa Mizuki Hidetoshi Inoko Thomas Spies Ioannis Theodorou Seiamak Bahram 《Immunogenetics》1996,44(5):351-357
The hallmark of the classical major histocompatibility complex (MHC) class I molecules is their astonishing level of polymorphism,
a characteristic not shared by the nonclassical MHC class I genes. A distinct family of MHC class I genes has been recently identified within the human MHC class I region. The MICA (MHC class I chain-related A) gene in this family is a highly divergent member of the MHC class I family and has a unique pattern of tissue expression. We have sequenced exons encoding the extracellular α1, α2,
and α3 domains of the MICA gene from twenty HLA homozygous typing cell lines and four unrelated individuals. We report the identification of eleven new alleles defined by
a total of twenty-two amino acid substitutions. Thus, the total number of MICA alleles is sixteen. Interestingly, a tentative superimposition of MICA variable residues on the HLA-A2 structure reveals a unique pattern of distribution, concentrated primarily on the outer edge of the MICA putative antigen
binding cleft, apparently bordering an invariant ligand binding site.
Received: 13 May 1996 / Revised: 29 May 1996 相似文献
2.
3.
Zhao-Jun Wei Miao Yu Shun-Ming Tang Yong-Zhu Yi Gui-Yun Hong Shao-Tong Jiang 《Molecular biology reports》2011,38(2):1121-1127
Prothoracicotropic hormone (PTTH) is one of key players in regulation of insect growth, molting, metamorphosis, diapause,
and is expressed specifically in the two pairs of lateral PTTH-producing neurosecretory cells in the brain. Analysis of cis-regulatory elements of the PTTH promoter might elucidate the regulatory mechanism controlling PTTH expression. In this study,
the PTTH gene promoter of Bombyx mori (Bom-PTTH) was cloned and sequenced. The cis-regulatory elements in Bom-PTTH gene promoter were predicted using Matinspector software, including myocyte-specific enhancer
factor 2, pre-B-cell leukemia homeobox 1, TATA box, etc. Transient transfection assays using a series of fragments linked
to the luciferase reporter gene indicated that the fragment spanning −110 to +33 bp of the Bom-PTTH promoter showed high ability
to support reporter gene expression, but the region of +34 to +192 bp and −512 to −111 bp repressed the promoter activity
in the BmN and Bm5 cell lines. Electrophoretic mobility shift assays demonstrated that the nuclear protein could specifically
bind to the region spanning −124 to −6 bp of the Bom-PTTH promoter. Furthermore, we observed that the nuclear protein could
specifically bind to the −59 to −30 bp region of the Bom-PTTH promoter. A classical TATA box, TATATAA, localized at positions
−47 to −41 bp, which is a potential site for interaction with TATA box binding protein (TBP). Mutation of this TATA box resulted
in no distinct binding band. Taken together, TATA box was involved in regulation of PTTH gene expression in B. mori. 相似文献
4.
Xin-Wen Hu Si-Xin Liu Jian-Chun Guo Ji-Tao Li Rui-Jun Duan Shao-Ping Fu 《Functional & integrative genomics》2009,9(3):351-361
Mabinlin II is one of the major sweet proteins stored in the seeds of Capparis masaikai Lévl. Its promoter region (779 bp) located 5′ upstream of the mabinlin II gene has been isolated and named as MBL-779 (GenBank
accession number, EU014073). This promoter contains two typical TATA box regions and a series of motifs related to seed-specific
promoters, such as ACGT motifs, RY motif, napin motif, and G box. The MBL-779 promoter drove GUS gene to transiently express in the embryos of bean, maize, and rice seeds or to constantly express in the embryos and anthers
of the transgenic Arabidopsis. The MBL-779 promoter regulated gene expression from approximately the 12th day and peaked on approximately the 16th day
after flowering in Arabidopsis. The −300-bp promoter region is a minimal sequence required to functionally regulate gene expression. The CAATs at −325 to
−322 bp and −419 to −416 bp and the region at −485 to −770 bp play a role in the quantitative regulation of gene expression.
The RY motif, CATGAC, at −117 to −112 bp and the ACGT within the G box (CACGTG) at −126 to −123 bp positively regulate gene
expression.
X.-W. Hu and S.-X. Liu have the same contribution as first author. 相似文献
5.
Yunfei Chen Hyun S. Lillehoj Chung-Hsin Hsu Susan L. Carpenter S. J. Lamont 《Immunogenetics》1997,45(4):242-248
A 0.7 kilobase (kb) DNA fragment from the 5′ flanking region of a chicken major histocompatibility complex (MHC) class II B gene was cloned into chloramphenicol acetyltransferase (CAT) reporter vectors and was transfected into a chicken macrophage
cell line that expresses a low level of MHC class II antigens. Positive orientation-dependent promoter activity of the chicken
DNA was evident in a reporter construct containing an SV40 enhancer. Deletion analysis of this 0.7 kb DNA fragment revealed
a short fragment in the 3′ end that was crucial for the promoter function and negative regulatory elements (NRE) located further upstream. The conserved MHC class II X and Y boxes did not have a significant effect on promoter activity. Sequence analysis of the 0.7 kb class II B gene upstream region suggests possible involvement of interferon (IFN), E twenty-six specific (ETS)-related proteins, and
other factors in regulating this promoter. A chicken T-cell line culture supernatant increased surface expression of MHC class
II antigens, as well as class II promoter activity, in this macrophage cell line. This first functional characterization of
a chicken MHC class II B gene promoter will aid in understanding the regulatory mechanisms that control the expression of these genes.
Received: 9 July 1996 / Revised: 7 October 1996 相似文献
6.
7.
The promoter of Brassica campestris Male Fertile 5 (BcMF5), a pollen coat protein member, class A (PCP-A) gene family, was isolated from Brassica rapa L. ssp. chinensis Makino (Chinese cabbage-pak-choi) by Thermal Asymmetric Interlaced Polymerase Chain Reaction (TAIL-PCR). Sequence analysis
suggested that the 605-bp promoter of BcMF5 appears to be a pollen promoter. In an attempt to confirm the promoter activity of BcMF5 promoter, −609 to +3 bp and −377 to +3 bp fragments of the upstream sequence of BcMF5 were inserted at the site upstream of the coding region of the uidA gene in the sense orientation to construct two deletion expression vectors. Transient expression analysis in onion epidermal
cells by particle bombardment showed that both −609 to +3 bp and −377 to +3 bp fragments of BcMF5 promoter were capable of driving β-glucuronidase gene expression. Furthermore, by Agrobacterium-mediated genetic transformation
method, Arabidopsis transgenic KanR plants were obtained. GUS assay analysis revealed that the promoter of BcMF5 induced gene expression at the early stage of anther development and drove high levels of GUS expression in anther walls,
upper regions of petals, pollen, and pollen tubes in the middle and late stage of anther development, but did not drive any
expression in sepals and pistils. 相似文献
8.
Xue-Feng Wu Chun-Lian Wang En-Bei Xie Ying Gao Ying-Lun Fan Pi-Qing Liu Kai-Jun Zhao 《Planta》2009,229(6):1231-1242
We have previously isolated a Brassica juncea cDNA encoding a novel chitinase BjCHI1 with two chitin-binding domains (Zhao and Chye in Plant Mol Biol 40:1009–1018, 1999). The expression of BjCHI1 was highly inducible by methyl jasmonate (MeJA) treatment, wounding, caterpillar feeding, and pathogenic fungal infection.
These observations suggest that the promoter of BjCHI1 gene might contain specific cis-acting elements for stress responses. Here, we report the cloning and characterization of the BjCHI1 promoter. A 1,098 bp BjCHI1 genomic DNA fragment upstream of the ATG start codon was isolated by PCR walking and various constructs were made by fusing
the BjCHI1 promoter or its derivatives to β-glucuronidase reporter gene. The transgenic Arabidopsis plants showed that the BjCHI1 promoter responded to wounding and MeJA treatment, and to treatments with either NaCl or polyethyleneglycol (PEG 6000), indicating
that the BjCHI1 promoter responses to both biotic and abiotic stresses. A transient gene expression system of Nicotiana benthamiana leaves was adopted for promoter deletion analysis, and the results showed that a 76 bp region from −695 to −620 in the BjCHI1 promoter was necessary for MeJA-responsive expression. Furthermore, removal of a conserved T/G-box (AACGTG) at −353 to −348
of the promoter greatly reduced the induction by MeJA. This is the first T/G-box element identified in a chitinase gene promoter.
Gain-of-function analysis demonstrated that the cis-acting element present in the 76 bp region requires coupling with the T/G-box to confer full magnitude of BjCHI1 induction by MeJA. 相似文献
9.
10.
We previously cloned and analyzed the 1,893-bp promoter region (−1,915 to −23) of the tomato (Lycopersicon esculentum) Lehsp23.8 gene, whose expression is induced by treatment with high or low temperatures, heavy metal, or abscisic acid (ABA). In our
present work, we examined how this expression is regulated. A comprehensive quantitative promoter deletion and base-substitution
analysis was conducted under various environmental conditions. The proximal region (−565 to −23 bp) of the Lehsp23.8 promoter harbors cis-regulatory elements that conferred high levels of heat-induced expression in transgenic tobacco. Mutation of the five proximal
HSEs (HSE1 to 5) of that promoter led to an absence of heat inducibility. The AT-rich regions between −255 bp and −565 bp
(AT-rich1 to 4) in the promoter might serve as enhancers for such heat-induced expression. Deletion and HSE mutation analysis
indicated that other cis-acting elements also function in response to low temperature, heavy metal, and ABA and that HSE1 to 5 act at least as cis-acting elements in multiple-stress responses of Lehsp23.8. These results reveal that those five proximal HSEs and AT-rich regions function interdependently in the expression of Lehsp23.8 in response to non-heat stresses. Furthermore, the putative elements CRT/DRE, AP-1, and ABRE in that promoter are not required
for multiple-stress induction. 相似文献
11.
Frequent segmental sequence exchanges and rapid gene duplication characterize the<Emphasis Type="Italic"> MHC</Emphasis> class I genes in lemurs 总被引:2,自引:2,他引:0
Go Y Satta Y Kawamoto Y Rakotoarisoa G Randrianjafy A Koyama N Hirai H 《Immunogenetics》2003,55(7):450-461
Major histocompatibility complex (MHC) class I genes have complicated and profound evolutionary histories. To reconstruct and better understand their histories, partial class I genes (exon 2–intron 2–exon 3) were sequenced in a sampling of prosimians (Strepsirhini, Primates). In total, we detected 117 different sequences from 36 Malagasy prosimians (lemurs) and 1 non-Malagasy prosimian (galago) representing 4 families, 7 genera, and 13 species. Unlike the MHC class II genes (MHC-DRB), MHC class I genes show a generally genus-specific mode of evolution in lemurs. Additionally, no prosimian class I loci were found to be orthologous to HLA genes, even at highly conserved loci (such as HLA-E, HLA-F). Phylogenetic analysis indicates that nucleotide diversity among loci was very small and the persistence time of the polymorphisms was short, suggesting that the origin of the lemur MHC class I genes detected in this study was relatively recent. The evolutionary mode of these genes is similar to that of classic HLA genes, HLA-A, HLA-B, and HLA-C, in terms of their recent origin and rarity of pseudogenes, and differs from them with respect to the degree of gene duplications. From the viewpoint of MHC genes evolution, some interlocus sequence exchanges were apparently observed in the lemur lineage upon phylogenetic and amino acid motif analyses. This is also in contrast to the evolutionary mode of HLA genes, where intralocus exchanges have certainly occurred but few interlocus exchanges have taken place. Consequently, the gene conversion model for explaining the generation of the MHC diversity among different loci can be thought to play more important roles in the evolution of lemur MHC class I genes than in that of HLA genes.Electronic Supplementary Material Supplementary material is available in the online version of this article at 相似文献
12.
The expression of nitrite reductase (NiR; EC 1.7.7.1), the second enzyme in the nitrate assimilatory pathway, is regulated
by nitrate as well as by end-products of nitrate assimilation, namely, glutamine (Gln) and asparagine (Asn). Nitrate induces
expression of the NiR gene. Previously, using deletion analysis of the spinach (Spinacia oleracea L.) NiR gene promoter in transgenic tobacco (Nicotiana tabacum L.) and in-vivo dimethyl sulfate footprinting, we had identified the region between −230 bp and −180 bp as being critical
for nitrate inducibility of this gene. In the present study, we show that the region from +1 to +67, which forms part of its
untranslated leader, is important for minimal induction in the presence of nitrate. Electrophoretic mobility shift assays
reveal concentration-dependent and competitive binding of a factor in tobacco nuclear extracts to this region. In the presence
of Gln or Asn, the expression of spinach NiR is repressed. This repression is observed with the full-length NiR promoter (−3100 bp)
as well as with the shortest promoter (−230 bp) that gives nitrate induction, which includes the +67 bp leader sequence. The
repressed expression of the gene is not the result of reduced nitrate accumulation in the presence of the nitrogen metabolites.
Received: 2 December 1997 / Accepted: 20 January 1998 相似文献
13.
14.
A new major histocompatibility complex class I b gene expressed in the mouse blastocyst and placenta
Susan L. Sipes Maxine V. Medaglia Deborah L. Stabley Craig S. DeBruyn Mark S. Alden Vicki Catenacci C. P. Landel 《Immunogenetics》1996,45(2):108-120
Because of the role major histocompatibility complex (MHC) class I b molecules may play during mouse embryonic development,
we thought it would be interesting to search for additional MHC class I b molecules that might be expressed in preimplantation
embryos, and in particular in the trophoblastic lineage. We therefore screened a mouse preimplantation blastocyst cDNA library
for MHC class I sequences. This search led to the identification and characterization of a new MHC class I b gene, blastocyst MHC. Sequences identical to the exons and 3′ untranslated region of this gene have been found in many laboratory mouse strains,
as well as in the related mouse species Mus spreciligus. The presence of this gene in mouse strains of different MHC class I haplotypes argues that blastocyst MHC is a unique, newly-described gene rather than a new allele of a previously described mouse MHC class I gene. Blastocyst MHC has the structure of an MHC class I b gene, with the six exons characteristic of T-region genes. It is linked to H2-D. The amino acid sequence encoded by this gene maintains all the features of a functional antigen-presentation domain. The
blastocyst MHC gene, like the human class I b gene HLA-G, is expressed at the blastocyst stage and in the placenta, and may be the mouse analog for HLA-G.
Received: 31 May 1996 / Revised: 19 August 1996 相似文献
15.
P. B. F. Ouwerkerk T. O. Trimborn F. Hilliou J. Memelink 《Molecular & general genetics : MGG》1999,261(4-5):610-622
Plant secondary metabolites of the terpenoid indole alkaloid (TIA) class comprise several compounds with pharmaceutical applications.
A key step in the TIA biosynthetic pathway is catalysed by the enzyme tryptophan decarboxylase (TDC), which channels the primary
metabolite tryptophan into TIA metabolism. In Catharanthus roseus (Madagascar periwinkle), the Tdc gene is expressed throughout plant development. Moreover, Tdc gene expression is induced by external stress signals, such as fungal elicitor and UV light. In a previous study of Tdc promoter architecture in transgenic tobacco it was shown that the −538 to −112 region is a quantitative determinant for the
expression level in different plant organs. Within this sequence one particular region (−160 to −99) was identified as the
major contributor to basal expression and another region (−99 to −37) was shown to be required for induction by fungal elicitor.
Here, the in vitro binding of nuclear factors to the −572 to −37 region is described. In extracts from tobacco and C. roseus, two binding activities were detected that could be identified as the previously described nuclear factors GT-1 and 3AF1,
based on their mobility and binding characteristics. Both factors appeared to interact with multiple regions in the Tdc promoter. Mutagenesis of GT-1 binding sites in the Tdc promoter did not affect the basal or elicitor-induced expression levels. However, induction of the Tdc promoter constructs by UV light was significantly lower, thereby demonstrating a functional role for GT-1 in the induction
of Tdc expression by UV light.
Received: 2 February 1998 / Accepted: 5 March 1999 相似文献
16.
We isolated and characterized a pollen-preferential gene, BAN102, from Chinese cabbage and analyzed the activity of its promoter. There were three or four copies of the BAN102 gene in the Chinese cabbage genome that specifically expressed in pollen and pollen tube. There were 2137 bp of BAN102 genomic clone comprising 186 bp of protein coding region, and 1178 bp of 5′ and 773 bp of 3′ non-coding regions. TATA box
were located at 1071 nt of the promoter region while the polyadenylation signal and polyadenylation site were at 1470 and
1486 nt of the 3′ non-coding region. BLAST search of BAN102 sequence showed that coding region of BAN102 gene was the greatest percent similarity with arabinogalactan protein (AGP23) gene from Arabidopsis thaliana. Promoter analysis using GUS gene as a reporter showed that the pollen-specificity of BAN102 resided within the −112 to −44 bp of proximal promoter from the transient expression in tobacco and Chinese cabbage plants. 相似文献
17.
18.
The Perilla (Perilla frutescens L. cv. Okdong) oleosin gene, PfOle19, produces a 19-kDa protein that is highly expressed only in seeds. The activity of the −2,015 bp 5′-upstream promoter region
of this gene was investigated in transgenic Arabidopsis plants using the fusion reporter constructs of enhanced green fluorescent protein (EGFP) and β-glucuronidase (GUS). The PfOle19 promoter directs Egfp expression in developing siliques, but not in leaves, stems or roots. In the transgenic Arabidopsis, EGFP fluorescence and histochemical GUS staining were restricted to early seedlings, indehiscent siliques and mature seeds.
Progressive 5′-deletions up to the −963 bp position of the PfOle19 promoter increases the spatial control of the gene expression in seeds, but reduces its quantitative levels of expression.
Moreover, the activity of the PfOle19 promoter in mature seeds is 4- and 5-fold greater than that of the cauliflower mosaic virus 35S promoter in terms of both
EGFP intensity and fluorometric GUS activity, respectively. 相似文献
19.
SBgLR (Solanum tuberosum genomic lysine-rich) gene was isolated from a potato genomic library using SB401 (S.
berthaultii 401) cDNA as probe. RT-PCR analysis of SBgLR gene expression profile and microscopic analysis of green fluorescent protein (GFP) expression in tobacco plants transformed
with SBgLR promoter-GFP reporters indicate that SBgLR is a pollen-specific gene. A series of 5′deletions of SBgLR promoter were fused to the β-glucuronidase (GUS) gene and stably introduced into tobacco plants. Histochemical and quantitative assays of GUS expression in transgenic
plants allowed us to localize an enhancer of SBgLR promoter to the region −345 to −269 relative to the translation start site. This 76 bp (−345 to −269) fragment enhanced GUS
expression in leaves, stems and roots when fused to −90/+6 CaMV 35S minimal promoter. Deletion analysis showed that a cis-element, which can repress gene expression in root hairs, was located in the region −345 to −311. Further study indicated
that the −269 to −9 region was sufficient to confer pollen-specific expression of GFP when fused to CaMV 35S enhancer.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Authors Zhihong Lang and Peng Zhou contributed equally to this work. 相似文献
20.
K. E. Orishchenko E. A. Elisaphenko A. E. Kel S. M. Zakian 《Russian Journal of Genetics》2009,45(10):1182-1191