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31.
Ali Asghar Moghadam Eemaeil Ebrahimie Seyed Mohsen Taghavi Ali Niazi Mahbobeh Zamani Babgohari Tahereh Deihimi Mohammad Djavaheri Amin Ramezani 《Molecular biotechnology》2013,54(3):756-769
A small number of stress-responsive genes, such as those of the mitochondrial F1F0-ATP synthase complex, are encoded by both the nucleus and mitochondria. The regulatory mechanism of these joint products is mysterious. The expression of 6-kDa subunit (MtATP6), a relatively uncharacterized nucleus-encoded subunit of F0 part, was measured during salinity stress in salt-tolerant and salt-sensitive cultivated wheat genotypes, as well as in the wild wheat genotypes, Triticum and Aegilops using qRT-PCR. The MtATP6 expression was suddenly induced 3 h after NaCl treatment in all genotypes, indicating an early inducible stress-responsive behavior. Promoter analysis showed that the MtATP6 promoter includes cis-acting elements such as ABRE, MYC, MYB, GTLs, and W-boxes, suggesting a role for this gene in abscisic acid-mediated signaling, energy metabolism, and stress response. It seems that 6-kDa subunit, as an early response gene and nuclear regulatory factor, translocates to mitochondria and completes the F1F0-ATP synthase complex to enhance ATP production and maintain ion homeostasis under stress conditions. These communications between nucleus and mitochondria are required for inducing mitochondrial responses to stress pathways. Dual targeting of 6-kDa subunit may comprise as a mean of inter-organelle communication and save energy for the cell. Interestingly, MtATP6 showed higher and longer expression in the salt-tolerant wheat and the wild genotypes compared to the salt-sensitive genotype. Apparently, salt-sensitive genotypes have lower ATP production efficiency and weaker energy management than wild genotypes; a stress tolerance mechanism that has not been transferred to cultivated genotypes. 相似文献
32.
Narges Zamani Amirhossein Khoshgoftarmanesh Majid Afyuni 《International journal of phytoremediation》2015,17(5):456-463
The effect of Neotyphodium endophytes on growth parameters and zinc (Zn) tolerance and uptake was studied in two grass species of Festuca arundinacea and Lolium perenne. Plants were grown under different Zn concentrations (control, 200, 400, 800, and 1800 mg kg?1) in potted soil for 5 months. The results showed that the number of plant tillers was 85 and 51% greater in endophyte infected Festuca (FaEI) and Lolium (LpEI), respectively, compared to their endophyte free (EF) plants. Roots and shoots dry weights in infected Festuca were 87 and 9% greater than non-infected counterparts but in opposite, EF Lolium had 47 and 8% greater root and shoot dry weights than LpEI. Endophyte infected Festuca and Lolium improved chlorophyll fluorescence as Fv/Fm at high concentrations of Zn, showing their better chlorophyll functions and significant reduction of Zn stress in endophyte infected plants. Shoots of endophyte infectedFestuca had 82% greater concentration of Zn than EF Festuca when grown in soil containing 1800 mg kg?1 Zn. Festuca and Lolium may tolerate high Zn concentration in soil without reduction in shoot and root growth. Endophyte infection in Festuca may help the grass accumulate and transport more Zn in aboveground parts under Zn-stress, thereby aiding phytoremediation of contaminated soils. 相似文献
33.
Autoradiographic method to screen for soil microorganisms which accumulate zinc. 总被引:1,自引:0,他引:1 下载免费PDF全文
An autoradiographic method was developed to screen for and isolate soil microorganisms which accumulate zinc (Zn). Diluted soil samples (Rubicon fine sand, Entic Haplorthods [pH 5.9]) were plated on soil extract-glucose agar containing radioactive 65Zn. After 7 days of incubation, individual colonies which accumulated sufficient 65Zn could be detected by autoradiography. These colonies were isolated and confirmed as Zn accumulators in pure culture by using the autoradiographic plate technique. Most Zn accumulators were filamentous fungi, identified as Penicillium janthinellum, Aspergillus fumigatus, and Paecilomyces sp. Isolates of Penicillium janthinellum were the most common Zn accumulators. The most abundant Zn-accumulating bacteria were Bacillus spp. The validity of the autoradiographic plate technique to differentiate soil microbes which accumulate Zn was examined independently by energy dispersive X-ray analysis in a scanning electron microscope. This method confirmed that fungal isolates which gave positive autoradiographic responses in the plate assay bioaccumulated more Zn in their biomass than fungal isolates from the same soil sample which gave negative autoradiographic responses. Thus, this technique can be applied to specifically screen for and isolate microbes from the environment which bioaccumulate Zn. 相似文献
34.
Soheila Matroodi Mostafa Motallebi Mohammadreza Zamani Mehdi Moradyar 《World journal of microbiology & biotechnology》2013,29(8):1517-1523
Chitinases have the ability of chitin digestion that constitutes a main compound of the cell wall in many of the phytopathogens such as fungi. Chitinase Chit42 from Trichoderma atroviride PTCC5220 is considered to play an important role in the biocontrol activity of this fungus against plant pathogens. Chit42 lacks a chitin binding domain (ChBD). We have produced a chimeric chitinase with stronger chitin-binding capacity by fusing to Chit42 a ChBD from Serratia marcescens Chitinase B. The fusion of ChBD improved the affinity to crystalline and colloidal chitin and also the enzyme activity of the chimeric chitinase when compared with the native Chit42. The chimeric chitinase showed higher antifungal activity toward phytopathogenic fungi. 相似文献
35.
Bashir Ahmad Ali Muhammad Yousafzai Ayaz Ali Khan Mohammad Attaullah Waqar Ali Saeed Ahmad Ghazala Yasmin Zamani Farhat Naz Sumayya Raziq Amjad Ali 《Saudi Journal of Biological Sciences》2021,28(8):4324-4328
Present study focuses on ameliorative potential of Typha elephantina leave’s aqueous (TE.AQ) extract against Paracetamol (PCM) induced toxicity in rabbits. We fed the male rabbits with 300 mg PCM in alone and in combination with TE.AQ at different doses i.e. (100, 200 and 300 mg/kg body weight) or silymarin (100 mg/kg) daily for 21 days. PCM in alone significantly (P < 0.5) increased serum urea, uric acid, creatinine, total protein, albumin, globulin and blood urea nitrogen. Serum sodium, potassium and magnesium level were high. The glutathione, radical scavenging activity and Thiobarbituric acid reactive substances were significantly reduced. Treatment with TE.AQ at dose rate 300 mg/kg body weight and Silymarin significantly ameliorated all the parameters when compared with PCM administered group. The 100 and 200 mg of TE.AQ showed no significant effects. The histopathological examination confirmed the therapeutic potential of TE.AQ. These results established the presence of natural antioxidants in Typha elephantina leaves. 相似文献
36.
Zahra Zamani Masoud Bahar Marie Agnès Jacques Mohammad Reza Lak Alireza Akhavan 《World journal of microbiology & biotechnology》2011,27(10):2371-2378
Xanthomonad-like bacteria that are associated with common bacterial blight of bean in Iran were identified on the basis of
their colonial morphology, biochemical and serological properties, presence of a specific DNA fragment using PCR primers and
pathogenicity on bean. Xanthomonas axonopodis pv. phaseoli (Xap) strains were further characterized using rep-PCR and restriction fragment length polymorphism (RFLP). RFLP profiles
generated by the restriction endonucleases RsaI, TaqI, HaeIII and Sau96I and rep-PCR analysis revealed that Iranian strains were relatively genetically homogenous. The similarity coefficients
among the strains ranged from 0.87 to 1. The genetic diversity coefficients among strains from three infected provinces, Isfahan,
Markazi and Lorestan, were 0.019, 0.072 and 0.033, respectively. The low overall level of polymorphism within Xap isolates
collected from the three Iranian infected regions could suggest that few initial inoculum introductions might have distributed
among these different bean-growing areas in Iran. 相似文献
37.
Peyman?Norouzi Mohammad?A.?MalboobiEmail author Katayoun?Zamani Hahman?Yazdi-Samadi 《In vitro cellular & developmental biology. Plant》2005,41(1):11-16
Summary Despite intensive efforts, a reproducible and reliable method for transformation of sugarbeet plants is still lacking. Having
examined several explants, we found that cells around the main vein of leaves of plantlets reared from tissue-cultured apical
meristems are sufficiently competent for transformation and subsequent regeneration. A transformation protocol was designed
by evaluating alterations in several parameters such as plant genotype, Agrobacterium strain, antibiotics, darkness and duration of co-culture period. An average transformation rate of 6.2% transformed shoots
per explant was achieved as judged by Southern blotting. Consistent inactivation of reporter genes was correlated to multiple
copies of transgenes present in some transformants. The necessary steps for rooting and planting of transformed shoots were
also established. 相似文献
38.
Kwintkiewicz J Spaczynski RZ Foyouzi N Pehlivan T Duleba AJ 《Biology of reproduction》2006,74(6):1034-1040
Insulin and moderate oxidative stress stimulate proliferation of ovarian theca-interstitial cells. The effects of these agents on selected signal transduction pathways were examined. PD98059 (inhibitor of MAP2K1, also known as MEK-1, upstream of extracellular signal-regulated protein kinases MAPK3/1, also known as ERK1/2), wortmannin (inhibitor of PIK3C2A, also known as PI3K), and rapamycin (inhibitor of FRAP1, also known as mTOR, upstream of RPS6KB1) each significantly decreased insulin and oxidative stress-induced proliferation of theca-interstitial cells. The greatest inhibition was observed in the presence of rapamycin; this effect occurred without a significant change in cell viability. Phosphorylation of AKT was stimulated by insulin only, while phosphorylation of MAPK3/1 and RPS6KB1 was increased by insulin and oxidative stress. Insulin-induced and oxidative stress-induced phosphorylation of RPS6KB1 was partly inhibited by wortmannin and partly by PD98059; the greatest inhibition was observed in the presence of a combination of wortmannin plus PD98059. Effects of insulin and oxidative stress on phosphorylation of RPS6KB1 were confirmed by kinase activity assays. These findings indicate that actions of insulin and oxidative stress converge on MAPK3/1 and RPS6KB1. Furthermore, we speculate that activation of RPS6KB1 may be in part induced via the MAPK3/1 pathway. 相似文献
39.
We describe the development of a method in which protein oxidation by H2O2 followed by ultrahigh-pressure liquid chromatography (UHPLC) coupled with electrospray ionization time-of-flight mass spectrometry (ESI-ToFMS) and multivariate analysis are used to detect alterations in conformational states of proteins. In the study reported here, an IgG1 monoclonal antibody in native and denatured conformational states was oxidized by treatment with hydrogen peroxide. Peptide fragments generated by tryptic digestion were then analyzed by UHPLC-ESI-ToFMS. After reducing noise and extracting peaks from the LC–MS data using MzExplorer, software developed in-house and based on Matlab, we were able to distinguish peptides arising from the native and denatured states of the oxidized protein by principal component analysis. Peptides containing residues, which are inclined to undergo oxidation, such as methionine, are founded to be particularly important in this approach. We believe that the methodology could facilitate attempts to characterize the conformational states of recombinant monoclonal antibodies and other proteins. 相似文献
40.
Non-insulin-dependent diabetes mellitus (NIDDM) is a complex disease with a very high degree of heritability. Linkage and
segregation analyses have not been very productive in identifying genes responsible for polygenic diseases such as NIDDM,
and the majority of the genes determining susceptibility to this disorder remain to be identified. Using a case-control study
design, we investigated the possible roles of genes coding for HLA class II antigens, tumor necrosis factor-α (TNF-α), and
immunoglobulin (Ig) allotypes (GM and KM) in a group of Caucasians from Belgium (214 NIDDM patients and 200 controls). All
genetic markers were determined by polymerase chain reaction-based methods. We demonstrate that particular homozygous genotypes
of TNF-α and GM and KM allotypes epistatically interact with HLA-DQα1Arg 52 and contribute to an increased relative risk of NIDDM.
Received: 3 January 1999 / Accepted: 18 March 1999 相似文献