共查询到20条相似文献,搜索用时 15 毫秒
1.
Ectomycorrhizas are formed between certain soil fungi and fine roots of woody plants. An important feature of this symbiosis
is the supply of photoassimilates to the fungus. Hexoses, formed from sucrose in the common apoplast at the root/fungus interface,
can be taken up by both plant and fungal monosaccharide transporters. Recently we characterised a monosaccharide transporter
from the ectomycorrhizal fungus Amanita muscaria. This transporter was up-regulated in mycorrhizas, thus increasing the hexose uptake capacity of the fungal partner in symbiosis.
In order to characterise host (Picea abies) root monosaccharide transporters, degenerate oligonucleotide primers, designed to match conserved regions from known plant
hexose transporters, were used to isolate a cDNA fragment of a transporter by PCR. This fragment was used to identify a presumably
full length clone (PaMST1) in a P. abies/A. muscaria mycorrhizal cDNA library. The entire cDNA code for an open reading frame of 513 amino acids, revealing best homology to H+/monosaccharide transporters from Ara- bidopsis, Saccharum and Ricinus. PaMST1 was highly expressed in the hypocotyl and in roots of P. abies seedlings, but not in needles. Mycorrhiza formation led to a slight reduction of PaMST1 expression. The results are discussed
with special reference to carbon allocation in ectomycorrhizas.
Received: 9 October 1999 / Accepted: 22 December 1999 相似文献
2.
Iwasaki Yukimoto Kato Teruhisa Kaidoh Toshio Ishikawa Atsushi Asahi Tadashi 《Plant molecular biology》1997,34(4):563-572
A recombinant protein with a cDNA that encodes the putative subunit of a rice heterotrimeric G protein was synthesized in Escherichia coli and purified. The recombinant protein (rGrice ) with an apparent molecular mass of 45 kDa was bound with guanosine 5-(3-O-thio)triphosphate with an apparent association constant (kapp) of 0.36. The protein also hydrolyzed GTP and its Kcat was 0.44. rGrice was ADP-ribosylated by activated cholera toxin.Monoclonal antibodies raised against rGrice reacted with a 45 kDa polypeptide localized in the plasma membrane of rice seedlings. The peptide map of this polypeptide after digestion with V8 protease was identical to that of rGrice . A 45 kDa polypeptide in the plasma membrane, as well as rGrice , was ADP-ribosylated by activated cholera toxin. The GTPase activity of the plasma membrane was stimulated 2.5-fold by mastoparan 7 but not mastoparan 17. These properties were similar to those of the subunits of heterotrimeric G proteins in animals, suggesting that the putative subunit is truly the subunit itself. 相似文献
3.
Molly Vernersson Gunnar Pejler Therese Kristersson Kjell Alving L. Hellman 《Immunogenetics》1997,46(6):461-468
As a step in the evolutionary studies of immunoglobulin E (IgE) and for the purpose of developing new reagents that will
facilitate a more detailed analysis of IgE-mediated inflammatory reactions in a large animal model, we here present the cloning
of the ε chain of IgE in the domestic pig (Sus scrufa). A partial cDNA clone for the ε chain of pig IgE was isolated by polymerase chain reaction (PCR) amplification using degenerate
primers directed against conserved regions in the second (CH2) and the fourth (CH4) constant domains of IgE. cDNA derived
from mRNA isolated from the spleen and lymph nodes of a pig actively sensitized with a protein extract from the nematode Ascaris suum was used as template. Screening of a spleen cDNA library with the partial cDNA clone as probe resulted in isolation of a
clone that contained the entire coding region. The nucleotide sequence was determined and was found to conform with the previously
identified mammalian ε-chain sequences. The highest degree of similarity was found to sheep IgE. A DNA construct encoding
a baculovirus signal sequence, a histidine hexapeptide, and the CH2-CH3-CH4 domains of the pig IgE ε chain was obtained by
PCR amplification. The construct was ligated into the baculovirus expression vector pVL1392. Infection of High Five insect
cells with recombinant baculovirus resulted in expression and secretion of a soluble 6 × His-CH2-CH3-CH4 protein product.
Received: 9 April 1997 / Revised: 28 May 1997 相似文献
4.
《Gene》1997,192(2):261-270
We have isolated and sequenced a genomic clone for a pancreatic α-amylase gene (amy) of the chicken (Gallus gallus). The gene is interrupted by nine introns, spans over 4 kb, and encodes a protein (AMY) of 512 aa that is 83% identical to the human pancreatic α-amylase enzyme. Southern blot analysis of chicken DNA revealed two distinct pancreatic amy loci. In addition, we have generated a cDNA from chicken pancreatic RNA corresponding to the coding sequence of the genomic clone. The cDNA was inserted into a yeast expression vector, and the resulting construct used to transform Saccharomyces cerevisiae cells. Transformed yeast cells synthesized and secreted active AMY enzyme, and the gel migration pattern of the α-amylase produced by the yeast cells was identical to that of the native chicken enzyme. 相似文献
5.
6.
Cheng Chun-Wen Lin Jin-Seng Liu Yu-Tien Yang Shang-Shyng 《World journal of microbiology & biotechnology》2000,16(3):225-230
An 8.4 kb Sau3AI DNA fragment containing the Streptomyces rimosus TM-55 -amylase gene (amy) was ligated to a vector pIJ702, named pCYL01, and cloned into amylase deficient mutant S. lividans M2 (amy
–). Subcloning study showed that the amy gene was localized in 3.3 kbKpnI-PstI fragment. The molecular weight of the purified -amylases of S. lividans M2/pCYL01 and S. rimosus TM-55 were estimated to be 65.7 kDa. Different sizes of recombinant plasmids carrying the amy gene had been retransferred into the parental strain of S. rimosus TM-55. Among these S. rimosus transformants, TM-55/pCYL01, TM-55/pCYL12 and TM-55/pCYL36 showed amylase activity 1.36- to 2.05-fold at the seventh day (1.61 to 2.42 units vs 1.18 units), and oxytetracycline (OTC) production 2.00- to 2.50-fold at the ninth day (approximate 140 to 170 g ml–1 vs 72 g ml–1), higher than that of S. rimosus TM-55 alone, respectively. These results showed that industrial microorganisms could be improved by genetic and metabolic engineering. 相似文献
7.
Hee-Ok Kim Jeong-Nam Park Hyun-Jung Sohn Dong-Jun Shin Chan Choi Suhn-Young Im Hwanghee Blaise Lee Soon-Bai Chun Suk Bai 《Biotechnology letters》2000,22(18):1493-1498
Genomic DNA and cDNA encoding the -amylase from the oomycete, Saprolegnia ferax, were cloned into Saccharomyces cerevisiae and analyzed. The Spl. ferax -amylase gene consisted of a 1350 bp open reading frame, encoding a protein of 450 amino acids with a calculated mass of 49353 Da, and was not interrupted by any intron. The deduced amino acid sequence of the -amylase gene had 42% similarity to the -amylase of Arabidopsis thaliana. The -amylase gene was expressed in Sacc. cerevisiae and its product was secreted into the culture medium. 相似文献
8.
Song J Imanaka H Imamura K Minoda M Katase T Hoshi Y Yamaguchi S Nakanishi K 《Bioscience, biotechnology, and biochemistry》2011,75(6):1194-1197
A gene of β-galactosidase from Bacillus circulans ATCC 31382 was cloned and sequenced on the basis of N-terminal and internal peptide sequences isolated from a commercial enzyme preparation, Biolacta(?). Using the cloned gene, recombinant β-galactosidase and its deletion mutants were overexpressed as His-tagged proteins in Escherichia coli cells and the enzymes expressed were characterized. 相似文献
9.
Ki-Woong Han Jinsang Yoo Eun-Joo Oh Jeong Jin Choi Hyun-Kyu Kim Suk-Tae Kwon 《Biotechnology letters》2001,23(5):379-384
The gene (bglT) encoding Thermus caldophilus GK24 -glycosidase (Tca -glycosidase) was cloned and sequenced. The gene contains an open reading frame encoding 431 amino acids with a M
r of 48 658 Da. The bglT gene was expressed under the control of tac promoter on a high-copy plasmid in E. coli. The recombinant Tca -glycosidase was purified 41.5-fold with a 59% yield and a specific activity of 83 U mg–1 protein. 相似文献
10.
Previous studies on the activity of the rice Gα promoter using a β-Glucuronidase (GUS) reporter construct indicated that Gα expression was highest in developing organs and changed in a developmental stage-dependent manner. In this paper, GUS activity derived from the rice Gα promoter was analyzed in seeds and developing leaves. In seeds, GUS activity was detected in the aleurone layer, embryo, endosperm and scutellar epithelium. In developing leaves, the activity was detected in the mesophyll tissues, phloem and xylem of the leaf sheath and in the mesophyll tissue of the leaf blade. The activity in the aleurone layer and scutellar epithelium suggests that the Gα subunit may be involved in gibberellin signaling. The activity in the mesophyll tissues of the leaf blade suggests that the Gα subunit may be related to the intensity of disease resistance. The pattern of the activity in the developing leaf also indicates that the expression of Gα follows a developmental profile at the tissue level.Key words: expression pattern, Gα subunit, GUS staining pattern, heterotrimeric G protein, riceThe rice mutant d1 is deficient in the heterotrimeric G protein α subunit (Gα). Recently it was found that the dwarfism phenotype of d1 is due to a reduction in cell numbers.1 This discovery has led to new questions regarding how rice Gα regulates cell number, and which other signaling molecules are involved in this process in various tissues and at different development stages. Studies of d1 suggest that rice Gα participates in both gibberellin signaling2–4 and brassinosteroid signaling.5–8 Promoter studies using the β-Glucuronidase (GUS) reporter indicate that Gα expression is highest in developing organs.1 In this paper, we report on the expression pattern of a Gα promoter::GUS construct in seeds and developing leaves of rice. 相似文献
11.
《Gene》1997,193(1):1-4
The canine (Canis familiaris) retinal rod transducin (GT) α, β1 and γ1 subunits were sequenced. Cloning of the cDNAs was accomplished by polymerase chain reaction (PCR) using degenerate and wild type retinal cDNA libraries as templates. The deduced amino acid sequences were highly similar to rod transducins from other species: GTα differed by 5 amino acids from the corresponding human sequence, whereas β1 and γ1 were identical to human sequences. The coding sequence of rod transducin was evaluated as a possible cause for the recessively inherited retinal rod-cone degeneration: there were no nucleotide differences between the wild type and retinal degenerate strains. 相似文献
12.
13.
14.
Three starch synthase (SS) genes, OsSSII-1, OsSSII-2 and OsSSII-3, were identified in rice (Oryza sativa L.) and localized to chromosomes 10, 2 and 6, respectively. The three OsSSII full-length cDNAs were cloned, and the predicted amino acid sequences were found to share 52–73% similarity with other members of the plant SSII family. The SS activity of each OsSSII was confirmed by expression and enzyme activity assay in Escherichia coli. Expression profile analysis revealed that OsSSII-1 was expressed in endosperms, leaves and roots; OsSSII-2 was mainly expressed in leaves, while OsSSII-3 was mainly expressed in endosperms. Similar to the OsSSI proteins, the OsSSII-2 and OsSSII-3 proteins were found in the soluble as well as the starch-granule-bound fractions in rice. The roles of the OsSSII proteins in starch biosynthesis in rice and the evolutionary relationships of the genes encoding monocotyledonous and dicotyledonous class-II SS enzymes are discussed.Abbreviations
CDS
Coding domain sequence
-
EST
Expressed sequence tag
- GB
Granule-bound
- Glc
Glucose
-
SS
Starch synthase 相似文献
15.
Yoshiki Fujii Takaji Matsutani Kazutaka Kitaura Satsuki Suzuki Tsunetoshi Itoh Tomohiko Takasaki Ryuji Suzuki Ichiro Kurane 《Immunogenetics》2010,62(6):383-395
The common marmoset (Callithrix jacchus) is useful as a nonhuman primate model of human diseases. Although the marmoset model has great potential for studying autoimmune
diseases and immune responses against pathogens, little information is available regarding the genes involved in adaptive
immunity. Here, we identified one TCR α constant (TRAC), 46 TRAJ (joining), and 35 TRAV (variable) segments from marmoset
cDNA. Marmoset TRAC, TRAJ, and TRAV shared 80%, 68–100%, and 79–98% identity with their human counterparts at the amino acid
level, respectively. The amino acid sequences were less conserved in TRAC than in TCRβ chain constant (TRBC). Comparative
analysis of TRAV between marmosets and humans showed that the rates of synonymous substitutions per site (d
S
) were not significantly different between the framework regions (FRs) and complementarity determining regions (CDRs), whereas
the rates of nonsynonymous substitutions per site (d
N
) were significantly lower in the FRs than in CDRs. Interestingly, the d
N
values of the CDRs were greater for TRBV than TRAV. These results suggested that after the divergence of Catarrhini from Platyrrhini, amino acid substitutions were decreased in the FRs by purifying selection and occurred more frequently in CDRβ than in CDRα
by positive selection, probably depending on structural and functional constraints. This study provides not only useful information
facilitating the investigation of adaptive immunity using the marmoset model but also new insight into the molecular evolution
of the TCR heterodimer in primate species. 相似文献
16.
A dextranase gene from Penicillium minioluteum (strain IMI068219) has been cloned, sequenced and expressed in Saccharomyces cerevisiae via fusion of the DNA segment encoding the mature dextranase protein with α-factor signal sequence, and insertion into the GAL1–controlled expression vector pYES2/CT. Galactose-induced expression yielded extracellular dextranase activity of 0.63 units/ml and cell-associated dextranase activity of 0.48 units/ml, after 24 h incubation. The dextranase construct was introduced into a strain of S. cerevisiae expressing the human cytochrome P450 3A4 (CYP3A4) and the cognate reductase, which was then used to develop a microplate toxicity bioassay. Toxicity was signalled as inhibition of dextranase activity, assayed fluorimetrically. This novel bioassay was assessed using six economically significant mycotoxins. 相似文献
17.
This paper presents the first study describing the isolation, cloning and characterization of a full length gene encoding Bowman–Birk protease inhibitor (RbTI) from rice bean (Vigna umbellata). A full-length protease inhibitor gene with complete open reading frame of 327 bp encoding 109 amino acids was cloned from rice bean seeds using degenerate primer set. BlastP search revealed that the RbTI encoded amino acid of approx 13.0 kDa and shared 99% homology each with BBI from Phaseolus parvulus, Vigna trilobata and Vigna vexilata. Phylogenetic tree also showed close relationship of RbTI with BBI from other members of Leguminaceae family. RbTI gene was further confirmed as intronless (GenBank accession no. KJ159908). The secondary and 3D-structural models for the RbTI were predicted with homology modeling. qRT-PCR studies revealed the highest RbTI expression in the seeds nearing maturity, whereas the low expression of the gene was noticed in young leaves. The isolated RbTI was successfully expressed in Escherichiacoli and the highest expression was recorded after 5.5 h of induction. Study on the inhibitory activity of expressed protein against the gut proteases of Hessian fly larvae revealed 87% inhibition. The novel RbTI gene will further broaden the pool of plant defense genes and could be an ideal choice for developing transgenic crops resistant to insect pests with high economic value. In addition, it has the potential to be used as a probe for selection of insect- and pathogen-resistant genotypes. 相似文献
18.
Interferon-α (IFN-α) genes have been cloned from a variety of animals, but information regarding crane IFN-α has not been reported to date. In this study, we cloned a full-length Red-crowned Crane interferon-α (crIFN-α) gene sequence consisting of a 486 bp partial 5′ UTR, 741 bp complete ORF and 559 bp partial 3′ UTR. This gene encodes a protein of 246 amino acids and shares 60 to 80% identity with avian IFN-α and less than 45% identity with mammalian IFN-α. The expression of crIFN-α with an N-terminal His-tag was investigated in Escherichia coli, and the protein was purified on a nickel column. To obtain activated proteins, crIFN-α inclusion bodies were renatured by dialysis. In vitro cytopathic inhibition assays indicated that the recombinant crIFN-α could inhibit the replication of vesicular stomatitis virus in chicken fibroblasts. These antiviral activities were abrogated by rabbit anti-crIFN-α antibodies in vitro. In addition, an immunofluorescence assay indicated that crIFN-α could be expressed in chicken fibroblasts and was primarily located in the cytoplasm. Taken together, our results suggest that the crIFN-α gene may play an important role in inhibiting the replication of viruses. 相似文献
19.
Like those in mammals, heterotrimeric G protein complexes have been implicated in signal transduction pathways in plants; however, the subunits themselves have not been isolated. In this study, the rice heterotrimeric G protein subunits α (Gα) and β (Gβ) were purified by affinity chromatography using anti-Gα and -Gβ antibodies and SDS-PAGE. Six and seven peptides, respectively, were identified by mass spectrometry and identified as the translation products of the Gα gene RGA1 and Gβ gene RGB1. During purification, the subunits dissociated easily from the G protein complex. 相似文献