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571.
Elham Forouzesh Ashwani Goel Sally A. Mackenzie Joseph A. Turner 《The Plant journal : for cell and molecular biology》2013,73(3):509-520
Turgor pressure in plant cells is involved in many important processes. Stable and normal turgor pressure is required for healthy growth of a plant, and changes in turgor pressure are indicative of changes taking place within the plant tissue. The ability to quantify the turgor pressure of plant cells in vivo would provide opportunities to understand better the process of pressure regulation within plants, especially when plant stress is considered, and to understand the role of turgor pressure in cellular signaling. Current experimental methods do not separate the influence of the turgor pressure from the effects associated with deformation of the cell wall when estimates of turgor pressure are made. In this paper, nanoindentation measurements are combined with finite element simulations to determine the turgor pressure of cells in vivo while explicitly separating the cell‐wall properties from the turgor pressure effects. Quasi‐static cyclic tests with variable depth form the basis of the measurements, while relaxation tests at low depth are used to determine the viscoelastic material properties of the cell wall. Turgor pressure is quantified using measurements on Arabidopsis thaliana under three pressure states (control, turgid and plasmolyzed) and at various stages of plant development. These measurements are performed on cells in vivo without causing damage to the cells, such that pressure changes may be studied for a variety of conditions to provide new insights into the biological response to plant stress conditions. 相似文献
572.
Elham Schokraie Uwe Warnken Agnes Hotz-Wagenblatt Markus A. Grohme Steffen Hengherr Frank F?rster Ralph O. Schill Marcus Frohme Thomas Dandekar Martina Schn?lzer 《PloS one》2012,7(9)
Tardigrades have fascinated researchers for more than 300 years because of their extraordinary capability to undergo cryptobiosis and survive extreme environmental conditions. However, the survival mechanisms of tardigrades are still poorly understood mainly due to the absence of detailed knowledge about the proteome and genome of these organisms. Our study was intended to provide a basis for the functional characterization of expressed proteins in different states of tardigrades. High-throughput, high-accuracy proteomics in combination with a newly developed tardigrade specific protein database resulted in the identification of more than 3000 proteins in three different states: early embryonic state and adult animals in active and anhydrobiotic state. This comprehensive proteome resource includes protein families such as chaperones, antioxidants, ribosomal proteins, cytoskeletal proteins, transporters, protein channels, nutrient reservoirs, and developmental proteins. A comparative analysis of protein families in the different states was performed by calculating the exponentially modified protein abundance index which classifies proteins in major and minor components. This is the first step to analyzing the proteins involved in early embryonic development, and furthermore proteins which might play an important role in the transition into the anhydrobiotic state. 相似文献
573.
Sima Taheri Thohirah Lee Abdullah Shri Mohan Jain Mahbod Sahebi Parisa Azizi 《Molecular breeding : new strategies in plant improvement》2017,37(3):40
Induced mutations have been used effectively for plant improvement. Physical and chemical mutagens induce a high frequency of genome variation. Recently, developed screening methods have allowed the detection of single nucleotide polymorphisms (SNPs) and the identification of traits that are difficult to identify at the molecular level by conventional breeding. With the assistance of reverse genetic techniques, sequence variation information can be linked to traits to investigate gene function. Targeting induced local lesions in genomes (TILLING) is a high-throughput technique to identify single nucleotide mutations in a specific region of a gene of interest with a powerful detection method resulted from chemical-induced mutagenesis. The main advantage of TILLING as a reverse genetics strategy is that it can be applied to any species, regardless of genome size and ploidy level. However, TILLING requires laborious and time-consuming steps, and a lack of complete genome sequence information for many crop species has slowed the development of suitable TILLING targets. Another method, high-resolution melting (HRM), which has assisted TILLING in mutation detection, is faster, simpler and less expensive with non-enzymatic screening system. Currently, the sequencing of crop genomes has completely changed our vision and interpretation of genome organization and evolution. Impressive progress in next-generation sequencing (NGS) technologies has paved the way for the detection and exploitation of genetic variation in a given DNA or RNA molecule. This review discusses the applications of TILLING in combination with HRM and NGS technologies for screening of induced mutations and discovering SNPs in mutation breeding programs. 相似文献
574.
Micro‐spatial separation and associated morphological adaptations in the original case of avian character displacement 下载免费PDF全文
Masoud Yousefi Mohammad Kaboli Soheil Eagderi Alireza Mohammadi Ali Rezaei Elham Nourani 《Ibis》2017,159(4):883-891
Divergent evolution between Western Rock Nuthatch Sitta neumayer and Eastern Rock Nuthatch Sitta tephronota is widely recognized as the original case study of character displacement. However, in their contact zone in the Zagros Mountains, Iran, the morphological differences important for niche segregation between the two species remain unknown. We investigated microhabitat use and morphological adaptations of the two species, predicting that morphological adaptations to different habitats in these two nuthatches have led to spatial segregation. Seventy‐seven birds were captured and measured in the contact zone and allopatric zone in Iran. Twenty‐two primary variables related to flight apparatus, functional foot apparatus and feeding apparatus were measured and 11 ratios of primary variables were calculated as secondary variables due to their importance in habitat use. We also measured environmental variables related to geological features, mineral substrates and vegetation cover at a random sample of 100 of the locations where a nuthatch was observed. Results of morphometric and habitat analyses indicated that, in addition to trophic niche segregation, the two nuthatch species also differ in their microhabitat use and show differences in morphological features accordingly. In many case studies of character displacement, much more interest has been focused on the morphological differences in feeding apparatus than on those relating to habitat use. We suggest that future studies of character displacement should pay more attention to spatial niche segregation between sympatric species rather than trophic niche segregation. 相似文献
575.
Sophie Debs Amy Cohen Elham Hosseini-Beheshti Giovanna Chimini Nicholas H. Hunt Georges E.R. Grau 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(2):325-331
Background
Malaria is a serious parasitic infection affecting millions of people worldwide each year. Cerebral malaria is the most severe complication of Plasmodium infections, predominantly affecting children. Extracellular vesicles are essential mediators of intercellular communication and include apoptotic bodies, microvesicles and exosomes. Microvesicle numbers increase during disease pathogenesis and inhibition of their release can prevent brain pathology and mortality.Scope of review
We explore the current knowledge on microvesicles and exosomes in cerebral malaria pathogenesis.Major conclusions
Microvesicles and exosomes are implicated in cerebral malaria pathogenesis, in the modulation of host immunity to Plasmodium, and in cell-cell communication. Blocking their production is protective in models of cerebral malaria, both in vivo and in vitro.General significance
While anti-malarial treatments exist to combat Plasmodium infections, increasing drug resistance presents a major challenge. In order to improve diagnosis and treatment outcomes, further research is required to better appreciate extracellular vesicle involvement in cerebral malaria. 相似文献576.
577.
The necrotrophic fungus Thanatephorus cucumeris (anamorph Rhizoctonia solani) is among the most important soil‐borne pathogens which causes tomato foot and root rot worldwide. We investigated virulence and genetic relationships among and within different taxonomic groups of R. solani from the tomato‐growing regions in the north‐east of Iran. Characterization of R. solani taxonomic groups revealed that, of 56 isolates, four were AG‐2‐1, 16 were AG‐3 PT, 21 were AG‐4 HG‐I and 15 were AG‐4 HG‐II. Because interprimer binding site (iPBS), which is based on amplification of retrotransposons, is known as novel and powerful DNA fingerprinting technology, we selected four iPBS primers, which can detect polymorphisms of tomato foot root and root rot pathogen, for investigating genotypic variability of the isolates. The iPBS analyses separated various taxonomic groups of R. solani and showed great diversity among the isolates, demonstrating that the R. solani isolates obtained from tomato were not a clonal population. Crop rotation strategies and geographic location seem to be important factors affecting genetic structure of the isolates. Pathogenicity tests on tomato cultivar ‘Mobil’ showed significant differences in the virulence of various isolates. The overall results indicated that isolates of AG‐3 and AG‐4 were more virulent than AG‐2‐1. There was no significant correlation between genetic diversity and virulence of the isolates. This is the first report of R. solani AG‐4 HG‐II, causing tomato foot and root rot. Also, our research is the first in assessment of genetic diversity in fungal populations using iPBS molecular markers. 相似文献
578.
579.
Quantification of sperm specific mRNA transcripts (PRM1, PRM2, and TNP2) in teratozoospermia and normozoospermia: New correlations between mRNA content and morphology of sperm 下载免费PDF全文
580.
Fatemeh Firouzi Amoodizaj Sevda Baghaeifar Elham Taheri Mahdieh Farhoudi Sefidan Jadid Maryam Safi Nasrin Seyyed Sani Saba Hajazimian Alireza Isazadeh Dariush Shanehbandi 《Journal of biochemical and molecular toxicology》2020,34(6)
Gastric cancer (GC) is one of the prevalent human malignancies and the third most common cause of cancer‐related death worldwide. The doxorubicin hydrochloride is one of the important chemotherapeutic anticancer agents, with a limited therapeutic efficacy for treatment of GC. Therefore, taking advantage of synergistic effects by strategies like combination therapy seems appropriate and promising in treatment of GC. The aim of this study was to investigate a novel method to enhance the therapeutic efficacy of doxorubicin (as a chemotherapeutic agent) by co‐administration of curcumin (as a bioactive herbal compound) in GC treatment. In the present study, the effects of curcumin, doxorubicin, and their combinations (Dox‐Cur) were evaluated on the viability, morphological features, tumor spheroid formation, migration, invasion, and apoptosis of gastric adenocarcinoma cell line (AGS). Moreover, expression levels of BAX, BCL‐2, and CASP9 genes were assessed among AGS cells treated with curcumin, doxorubicin, and Dox‐Cur. The obtained results showed that all of curcumin, doxorubicin, and Dox‐Cur treatments significantly decreased the viability, tumor spheroid formation, migration, and invasion in the GC model cells. Furthermore, apoptosis rates in AGS cells were increased in a concentration‐ and time‐dependent manner in all of the treatment groups. Moreover, the anticancer activity of the Dox‐Cur combination was significantly more than curcumin and doxorubicin treatments alone. According to the results, Dox‐Cur combination therapy exerts more profound apoptotic and anticancer effects on the AGS cell line than curcumin or doxorubicin monotherapy. 相似文献