We have broadly defined the DNA regions regulating esterase6 activity in
several life stages and tissue types of D. melanogaster using P-
element-mediated transformation of constructs that contain the esterase6
coding region and deletions or substitutions in 5' or 3' flanking DNA.
Hemolymph is a conserved ancestral site of EST6 activity in Drosophila and
the primary sequences regulating its activity lie between -171 and -25 bp
relative to the translation initiation site: deletion of these sequences
decrease activity approximately 20-fold. Hemolymph activity is also
modulated by four other DNA regions, three of which lie 5' and one of which
lies 3' of the coding region. Of these, two have positive and two have
negative effects, each of approximately twofold. Esterase6 activity is
present also in two male reproductive tract tissues; the ejaculatory bulb,
which is another ancestral activity site, and the ejaculatory duct, which
is a recently acquired site within the melanogaster species subgroup.
Activities in these tissues are at least in part independently regulated:
activity in the ejaculatory bulb is conferred by sequences between -273 and
-172 bp (threefold decrease when deleted), while activity in the
ejaculatory duct is conferred by more distal sequences between -844 and
-614 bp (fourfold decrease when deleted). The reproductive tract activity
is further modulated by two additional DNA regions, one in 5' DNA (-613 to
-284 bp; threefold decrease when deleted) and the other in 3' DNA (+1860 to
+2731 bp; threefold decrease when deleted) that probably overlaps the
adjacent esteraseP gene. Collating these data with previous studies
suggests that expression of EST6 in the ancestral sites is mainly regulated
by conserved proximal sequences while more variable distal sequences
regulate expression in the acquired ejaculatory duct site.
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Four new Dactylogyrus species are described and two redescribed from cyprinids of the River Tigris, Iraq. These are as follows: Dactylogyrus barbioides n. sp. from Barbus grypus; D. orbus n. sp. from Barbus lacerta; D. barbuli n. sp. from Barbus barbulus; D. macrostomi n. sp. from Cyprinion macrostomi; D. pavlovskyi Bychowsky, 1949 from Barbus grypus and Barbus sharpeyi; and D. inutilis Bychowsky, 1949 from Barbus xanthopterus. A phylogenetic and zoogeographical analysis is presented. 相似文献
Citrus Tristeza Virus (CTV), usually occurs in nature as a mixture of genotypes. Six naturally infected citrus
(Citrus sinensis) trees grafted on sour orange rootstock were collected from three citrus growing governorates
in Egypt (Sharqia, Qalyubia and Garbia). In this study, RT-PCR, Single-Strand Conformation Polymorphism
(SSCP) and nucleotide sequence analysis were used for four independent CTV genomic regions (p65, p18,
p20, and p23) to detect and assess the sequence and genetic variabilities among CTV Egyptian isolates. RTPCR products (650 bp) for the CTV p23 gene obtained from the selected isolates were used for the SSCP analysis
and DNA sequencing. SSCP patterns of p23 gene for individual isolates yielded different complex haplotype patterns. Nucleotide sequence analysis of p23 region amplified from six isolates under study revealed that p23 shared
high nucleotide identity 98.7% with T36 isolate from USA, Florida. Phylogenetic analysis of p23 gene indicated a
close evolutionary relationship between all examined isolates and Qaha isolate (T36 isolate group), suggesting that
they may have originated from closely related ancestors. Nucleotide sequence analysis of the three genes located
on CTV 3′-coterminal overhang, p18, p20 and p65, amplified from isolate A3, Sharqia governorate, revealed that
the p18, p65, and p20 genes were related to the T3-KB isolate from South Africa with 99%–100% sequence
homology. Phylogenetic relationship analysis for p65, p18 and p20 ORFs clustered the current A3 isolate with
T3 genotype group. The recombination analysis identified three of six isolates from Sharqia, and Garbia as potential recombinant for p23 gene. The isolates T36 and T3 were identified as major donors for recombination events
in isolate A3. Our results concluded that p23 ORF likely to be as a hotspot region for recombination and originated through recombination event. The current study indicated that recombination is an important factor for the
origin of CTV strains in Egypt. 相似文献
Production of peaches (Prunus persica (L.) Batsch) for both local market and export is increasing each year in
Egypt. Brown rot disease, caused by Monilinia laxa and Monilinia fructigena, is considered one of the most
important postharvest rots affecting peaches in Egypt and economic losses are increasing. Antifungal activity
of glycyrrhizic acid nanoparticles (GA-NPs) and glycyrrhizic acid (GA) at 0.2 and 0.4 mmol/L was investigated
as a control for both these brown rot pathogens on peach fruits in both in vitro and in vivo studies. In the in vitro
studies, GA-NPs were the most effective as shown by the ability to decrease linear growth of both brown rot
pathogens in potato dextrose agar (PDA) amended with 0.4 mmol/L GA-NPs. Micrographs of M. fructigena
exposed to 0.4 mmol/LGA showed mycelial deformations, nodule formation, detachment of the cell wall, shrinkage and inhomogeneous cytoplasmic materials with large vacuoles. Mycelium of M. laxa exposed to 0.4 mmol/
LGA-NPs resulted in thinner and distorted hyphae, nodule formation, cell wall thinning, and swellings. The GANPs and GA treatments improved fruit quality by maintaining firmness and total soluble solids (TSS). GA-NPs
were more effective in decreasing decay incidence than their bulk material. The 0.4 mmol/L GA-NPs completely
inhibited the disease on naturally infected peach fruits for both seasons of 2018 and 2019. Furthermore,
0.4 mmol/L GA-NPs reduced the disease incidence in inoculated fruits by 95 (M. laxa) and 88% (M. fructigena)
in 2018 season and 96 (M. laxa) and 85% (M. fructigena) in 2019 season. In conclusion, GA-NPs could enhance
the resistance of peaches against brown rot caused by M. laxa and M. fructigena. 相似文献
Low-temperature and high humidity are typical environmental factors in the plastic tunnel and solar greenhouse during the cold season that restricts plant growth and development. Herein, we investigated the impact of different combinations of low-temperature and high humidity (day/night: T1 15/10 °C?+?95%, T2 12/8 °C?+?95%, and T3 9/5 °C?+?95%) along with a control (CK 25/18 °C?+?80%) on cucumber cultivars viz: Zhongnong37 (ZN37: resistant) and Shuyanbailv (SYB: sensitive). The low-temperature and high humidity stresses increased electrolyte leakage (EL), malondialdehyde (MDA), hydrogen peroxide (H2O2) and intercellular concentration of carbon dioxide (Ci), and reduced morphological indices, relative water content (RWC), net photosynthesis rate (Pn), stomatal conductance (Gs), transpiration rate (E) and leaf pigments in both cultivars as compared to control (CK). Superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) were decreased in cv. SYB under stress conditions as compared to cv. ZN37. Low-temperature and high humidity treatments showed an increase in proline and soluble protein content in cv. ZN37 as compared to cv. SYB. Abscisic acid (ABA) and jasmonic acid (JA) were augmented while indole-3-acetic acid (IAA), zeatin (ZT), zeatin riboside (ZR), and gibberellic acid (GA) were decreased in both cultivars. Under T3 (9/5 °C?+?95%), Pn, protoporphyrin, and ZT were extremely decreased by 71.3%, 74.3%, and 82.4%, respectively, in cv. SYB compared to control. Moreover, principal component analysis (PCA) based on physiochemical traits confirmed that cv. ZN37 had the strongest correlation with antioxidant enzymes, proline, and soluble protein content than cv. SYB under low-temperature and high humidity treatments. Our results suggest that a stress-tolerant cultivar mitigates stress damage in cucumber transplants by regulating photosynthetic efficiency, antioxidant capacity and hormonal profile when compared to a stress-sensitive cultivar.
Cancer is one of the main challenges of the health system around the world. This disease is increasing in developing countries and imposes heavy costs on patients and governments. On the other hand, despite various drugs, the death rate among cancer patients is still high and the current treatments have many harmful effects. In the traditional medicine of different countries, there are many medicinal plants that can be effective in the treatment of cancer. Ferula plants are traditionally used as spices and food or for medicinal purposes. Ferula assa-foetida is one of the famous plants of this genus, which has been used for the treatment of various diseases since ancient times. Among the main compounds of this plant, we can mention monoterpenes, sulfide compounds and polyphenols, which can show different therapeutic effects. This article has been compiled with the aim of collecting evidence and articles related to the anti-cancer effects of extracts, derived compounds, essential oils and nanoparticles containing Ferula assa-foetida. This review article was prepared by searching the terms Ferula assa-foetida and cancer, and relevant information was collected through searching electronic databases such as ISI Web of Knowledge, PubMed, and Google Scholar. Fortunately, the results of this review showed that relatively comprehensive studies have been conducted in this field and shown that Ferula assa-foetida can be very promising in the treatment of cancer. 相似文献
The current study was designed to evaluate the antioxidant, anticancer and antimicrobial activities of silver nanoparticles (AgNPs) biosynthesized by Spirulina platensis extract. The biosynthesized silver nanoparticles were characterized using Fourier transform infrared (FT-IR) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The antioxidant activity of the biosynthesized AgNPs were determined via DPPH radical scavenging assay while its anticancer activity was determined using the MTT assay. The antimicrobial activity of the biosynthesized AgNPs were analyzed by disc diffusion method. Spirulina platensis acts as a reducing and capping agent. The efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Gram-negative bacteria, specifically Acetobacter, Klebsiella, Proteus vulgaris, and Pseudomonas aeruginosa, was assessed by the utilisation of the diffusion method. The study aimed to evaluate the efficacy of biosynthesized silver nanoparticles (AgNPs) against many strains of Pseudomonas aeruginosa bacteria. The findings of the study revealed that when administered in doses of 50 μl, 75 μl, and 100 μl, the largest observed zone of inhibition corresponded to measurements of 10.5 mm, 14 mm, and 16 mm, respectively. A zone of inhibition with dimensions of 8 mm, 10.5 mm, and 12 mm was detected during testing against Acetobacter at concentrations of 50 μl, 75 μl, and 100 μl, respectively. The findings also indicate that there is a positive correlation between the concentration of AgNP and the DPPH scavenging ability of silver nanoparticles. The percentage of inhibition observed at concentrations of 500 μg/ml, 400 μg/ml, 300 μg/ml, 200 μg/ml, and 100 μg/ml were recorded as 80±1.98, 61±1.98, 52±1.5, 42±1.99, and 36±1.97, respectively. In addition, it was observed that the silver nanoparticles exhibited the greatest antioxidant activity at a concentration of 500 g/ml, with a measured value of 80.89±1.99. The IC-50 values, representing the inhibitory concentration required to achieve 50 % inhibition, were found to be 8.16, 19.15, 30.14, 41.13, and 63.11 at inhibition levels of 36±1.97, 42±1.99, 52±1.5, 61±1.98, and 80±1.98, respectively. 相似文献
Intraspecific variation among 84 isolates of the anamorphic fungusChaunopycnis alba from 26 different geographical locations was analyzed by investigating optimal growth temperatures, differences in the production of secondary metabolites and presence or absence of the cyclosporin synthetase gene. The genetic diversity was assessed using random amplified polymorphic DNA (RAPD). Analysis of these data showed high genetic, metabolic and physiological diversity within this species. Isolates from the Antarctic represented the most homogeneous group withinC. alba and together with isolates from the Arctic these polar strains differed from alpine, temperate and tropical strains by low optimal growth temperatures and by low production of secondary metabolites. Isolates from tropical climes were characterized by high optimal growth temperatures and by the production of comparatively diverse metabolite spectra. Most of the isolates that were similar in the combination of their physiological and metabolic characters were also genetically related. Isolates from different geographical origins did not show many similarities, with the exception of the cyclosporin A-producing isolates, and large diversity could be observed even within a single habitat. This leads us to the suggestion that for pharmaceutical screening programs samples should be collected from a diversity of different geographical and climatic locations. For the selection of strains for screening the RAPD assay seems to be the most powerful tool. It reflected the highest intraspecific diversity and the results corresponded well with the other characteristics. 相似文献