مجله پژوهش های سلولی مولکولی (زیست شناسی ایران)
سال سی و چهارم شماره 3 (پاییز 1400)

HtrA2 is the mitochondrial serine protease, expressed in almost all tissues. At stressful conditions, this protease is converted into a pro-apoptic factor and induces apoptosis. It has been showed that beside protease function, HtrA2 acts as a chaperone and is involved in the proper protein folding. Considering the importance of the HtrA2 enzyme in inducing apoptosis and its association with some diseases, the expression pattern of HtrA2 protein was evaluated in natural cell lines and some disease categories. PCR results obtained in the present study showed that the normal human gastric tissue express HtrA2 gene, but the HtrA2 gene was not expressed in gastric cancer form. Also, HtrA2 gene was expressed in human lung cancer tissue, SW480 cell lines and MS cell lines. According to different expression of HtrA2 gene in natural and diseases tissues and cell lines, there was no specific pattern indicating the association of expression of this protease with a disease. In the next step, due to the importance of HtrA2, the coloning of HtrA2 gene in pET21a (+) (expression vector) has been done and the recombinant vector was transformed to the E. coli TOP10 strain cells. Finally, protein expression was analyzed with SDS-PAGE electrophoresis. Then, the produced protein was purified with Ni-NTA Agarose and protease activity of HtrA2 was assayed by casein substarte with spectrophotometer. The results showed the produced protein is active, so the produced HtrA2 has natural structure and can be used for further research.

vAcetylcholinesterase inhibitors (anticholinesterases) are commonly used to improve the symptoms of Alzheimer's disease and the other forms of dementia and central nervous system disorders. Propolis is a sticky resinous substance produced by honey bees and exhibits a variety of biological activities such as anticancer, antioxidant, antimicrobial and antifungal. Recently, a number of articles have been published on the anticholinesterase activity of propolis. In this study, the interaction of 17 propolis flavonoid compounds with human acetylcholinesterase (hAChE) was investigated using molecular docking. These studies were performed with AutoDock Vina software and the grid box was designed to be placed on the active site gorge of the enzyme. The results obtained showed that all these compounds bind to this region with very good binding energy (-7 to -8.9 kcal/mol). The highest and lowest binding energies are related to rutin and fisetin, respectively. Investigation of the amino acids involved in the interaction demonstrated that all of these compounds interact with PAS and acyl pocket. The two compounds, caffeic acid phenethyl ester (CAPE) and myricetin, also interact with CAS and oxyanion hole. Myricetin is the only compound that has the ability to bind to two amino acids belonging to the catalytic triad. The results of this study suggest that all of these flavonoid compounds have the ability to inhibit the hAChE activity by binding to the active site gorge of the enzyme and are therefore suitable candidates for further studies to design new anticholinesterase drugs.

Colorectal cancer as the most common cancer of the digestive tract is the fourth leading cause of death in the world. According to studies, miRNA-34a (miR-34a) expression declines in colon cancer. The aim of this study was to investigate the effect of miR-34a on growth and migration inhibition and apoptosis induction of colon cancer cells.In this experimental study, HCT116 human colorectal cancer cells were used in RPMI1640 medium. MiR-34a transmission into cancer cells was performed by the jetPEI transfection reagent. MTT assay to determine the survival of cancer cells and the qRT-PCR test to confirm the transfer of miR-34a to the cells and also an investigation of the expression of Caspase genes were used. Finally, the Wound healing test in order to investigate the migration status of transfected and control cells was performed. The expression changes of the intended genes in the transfected cells were compared with the control cells using the 2-ΔΔCt method.The MTT test showed that induction of miR-34a causes the death of colorectal cancer cells. Also, the results of the qRT-PCR test revealed a significant increase of miR-34a in the HCT116 transfected cells compared to the control as well as increased expression of Caspase genes in transfected cells. Ultimately, the results of the Wound healing test showed reduced migration of transfected cells compared to the control cells. The study showed that miRNA-34a plays an important role in inhibiting the growth and migration of colon cancer cells and can be a candidate for molecular therapies.

Early blight is one of the major diseases of tomato that reduce the quality and quantity of the product. Regarding the molecular mechanisms involved in the host defense to the pathogen, little information is available to realize the mechanisms of defense response of tomato to pathogenic fungus Alternaria solani. In this research, the protein profile (proteome) of tomato leaves were investigated using two-dimensional electrophoresis. A total of 610 detection protein showed 29 different expression proteins in resistant and susceptible cultivars. These proteins mainly involved in stress and defense, energy and metabolism, photosynthesis, protein biosynthesis, and signal transduction. Proteins involved in stress and defense such as pathogencity related proteins (PR) and biosynthesis of phenolic metabolite were the most frequent. The most important defense mechanisms of the plant against A. solani were strengthening of the cell wall and antimicrobial phenolic compounds. The results of this study can be used to production of resistant varieties of tomato against A.solani.

In this paper, the interactions between paclitaxel molecule and asteropsin_A protein in the aqueous media have been studied by molecular dynamics simulation and MM-PBSA method. The binding energies between paclitaxel and asteropsin_A have been evaluated by the help of MM-PBSA in these systems after equilibration and simulation. The main goal of this study is investigated the active sites to create effective interactions between drug nanoparticles and proteins and also to form a framework for drug by proteins, for this purpose used one, two, three, four and five asteropsin_A. The results of molecular dynamics simulations, such as radius of gyration, radial distribution functions and hydrogen bonding, have been discussed. The results were analyzed by the comparing their values in the systems with and without Paclitaxel. The results show that by increasing the number of asteropsin_A in the systems, the solubility of paclitaxel in water increases. Also, the results show that the residues Gly2, Leu21, Cys3, Phe14 and PGa1 have maximum interactions with paclitaxel in the systems containing one, two, three, four and five asteropsin_A proteins, respectively. The results represent that increasing the number of asteropsin A, lead to increasing the binding affinity of drug to proteins.

Circulating miRNAs have also been proposed as novel biomarkers for early diagnosis and even prognosis of cancer. Due to the non-invasive access, in addition to before metastase early detection, the use of these molecules can reduced injuries of patients. In this study, the biosensor was designed to isolate circulating mi RNAs by microfluidic system. The design was based on the isolation of two miRNAs (miR-21 and miR-486), which have been described in papers as miRNAs with potential to diagnosis of lung cancer.In this system, miRNA isolation is performed using a capture probe (single-strand DNA), immobilized by GPTMS linker on PDMS surface. By attaching of microRNA to this probe, the second probe that was biotinilated DNA complement to upper portion of microRNA, attaches to it and creates a sandwich structure. Eventually, trapped microRNA between two probes was detected by FITC- streptavidin. miRNA has been visualized under IX81 Olympus florescent microscope.

The S. cerevisiae is a unique microorganism in toxic metals biosorption. The extracellular uptake of zinc in S. cerevisiae mediated by the high-affinity Zrt1 protein as zinc transporter. The aim of current study was to examination of Zrt1 gene expression level in the presence of zinc metal, in S. cerevisiae as an industrially important yeast strain.

Yeast isolates, obtained from alcohol factory’s effluent were filtered and grown in YPD (yeast extract-peptone-dextrose) medium as a specific medium for yeast growth. The PCR method and DNA sequencing was employed to identify S. cerevisiae yeasts strains. Then, growth rate of this yeast in present of different concentration of Zn2+, was examined at 24-hour intervals (0, 24, 48, and 72 h), using spectrophotometry. The qRT-PCR technique was carried out to quantified expression level of Zrt1 in yeast cells under these conditions. Also, the protein-protein interaction (PPI) network of Zrt1 and its closely interacting genes, obtained from STRING database were analyzed using Network Analyzer (plugged in Cytoscape v3.7.0) to identify the most potentially effective genes.

In optimum conditions of 25 µg/ml of zinc after 24 h incubation, S. cerevisiae showed the maximum growth rate and expression level of Zrt1 as Zn transporter. Also, bioinformatics analyses identified Zrt1 as crucial gene in cell signaling pathway for zinc absorption by S. cerevisiae.

our study demonstrated that S. cerevisiae, obtained from industrial effluents, can be used to produce Zn-enriched biomass.

As a high value crop with natural tolerance for drought conditions, Quinoa (Chenopodium quinoa Willd) is an excellent candidate for improving food safety and food quality. It's an Amaranthacean, stress-tolerant plant cultivated along the Andes for the last 7000 years. Quinoa seeds represent potential rich sources of polyphenol compounds; they may protect cell constituents against oxidative damage and therefore limit the risk of various degenerative diseases associated to oxidative stress. In this study cellular and biochemical parameters include of total phenolic content, total free amino acids, superoxide dismutase activity, leaf total soluble protein, soluble protein SDS-PAGE and chromosomal observation in quinoa varieties cultivated in climate condition of meimeh Isfahan were investigated. Optical microscope was not a good tool for studying quinoa chromosomes. The total phenol content amongst the five quinoa varieties was significantly higher in Q29 (12.90±2.62 μg GA/mg seed). Analysis of variance of total content of free amino acids revealed significant .

Pseudomonas is considered as one of the most opportunistic and pathogenic microbes. Due to its high resistance to antibiotics, this bacterium has also encouraged the researchers to introduced alternative therapies, including phage therapy.

Recognition of the family of phages affecting the family of Pseudomonas and evaluation of the immunogenicity of antimicrobial lysine are considered here.

Here, the physio-chemical features of the family of phages affecting the bacterium Pseudomonas was investigated using bioinformatic and immunoinformatic databases. The secondary and tertiary structures of the lysines and the capacity of antigenicity in the host cells were determined.

The results showed that the three bacteriophage families Siphoviridae, Myoviridae, podoviridae with more than 90% abundance had the highest frequency among the bacteriophage families affecting Pseudomonas genus. Analyses of the lysine sequences of each of these three families showed immunity in only half of the total amino acids with a numerial value of half of the threshold of the software for B cells. 1% of amino acids had a strong affinity for MHC molecules those subjected to T cells. Total resulting:Due to the low induction of the immune response by phage lysine protein, they can be a candidate as alternative therapies for antibiotic resistance.

Fenugreek is an important medicinal plants that has valuable secondary metabolites. Diosgenin, a steroid saponin, occurs abundantly in fenugreek which has many medicinal properties. Anticancer activity of diosgenin has been reported in many studies. In this study the expression of some key genes involved in the biosynthesis of diosgenin, was assessed. First, plants (before flowering stage) were treated with 0.5 mM methyl jasmonate and 1 mM salicylic acid in separate experiments. Then, at 0, 12, 24, and 48 hours after treatment, leaves were sampled for further investigation. The total RNA was extracted from the leaves and afterward cDNA was synthesized. Selected key genes included cycloartenol synthase (CAS), squalene synthase (SQS), and squalene monooxygenase (SMO). To verify the sequence of the genes, the amplified fragments of them were separately cloned into the pTG19-T vector and their targeted region were finally sequenced. After confirming the sequence of selected genes, the relative expression level of all of the target genes was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR) method. The results showed that the expression level of CAS in salicylic acid-treated plants did not change compared to control plants, however, expression levels of SQS and SMO were increased at some time courses. While, CAS, SQS and SMO expression levels in methyl-jasmonate treated plants were significantly increased in comparison with control plants. Considering the expression of the key genes in the biosynthesis pathway of diosgenin suggests that diosgenin is likely to increase in response to salicylic acid and in particular methyl jasmonate.

Considering the undesirable side effects of synthetic antioxidants and antibiotics on human health and increasing the antibiotic resistance of pathogens, it is necessary to identify safe alternative sources for these compounds. In this study, antioxidant and antimicrobial activity of Mentha spicata methanolic extract were evaluated. The extract of leaves was prepared using Soxhlet extractor and methanol as solvent. The total phenol and flavonoid content were determined by folin-ciocalteu reagent and aluminum chloride colorimetric method, respectively. The antioxidant activity of M. spicata was determined via DPPH method. Also, the antimicrobial activity was evaluated by the agar well diffusion method and minimum inhibitory concentration (MIC) against various types of microorganisms. The extraction yield of M. spicata leaves was 22.60%. Also, the total phenol and flavonoid content were 278.537μg/mg dry weight of the extract in gallic acid equivalent and 75.579μg/mg dry weight of the extract, respectively. The IC50 of the methanolic extract of leaves and butylated hydroxytoluene were 61.243μg/ml and 19.8μg/ml, respectively. Based on the results of the agar well diffusion method and MIC, the most inhibitory effect of M. spicata extract was observed against Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Klebsiella pneumonia and Staphylococcus aureus, respectively and had no effect on fungi. According to the results of this study, M. spicata extract has desired antioxidant and antimicrobial activity.

Apiaceae is one of the largest plant families with a wide distribution including 114 genera and 363 species in Iran. Heracleum consists more than 100 species in the world, eight of them being reported in Iran including three endemic species. Based on taxonomic descriptions in Flora Iranica, the species reported in Pubescentia and Wendia sections have several morphological similarities and some display extensive geographical variation. We used the nuclear ITS and the chloroplast rpl32-trnL nucleotide sequences were used to evaluate the genetic relationships of different populations of Heracleum species. The Bayesian analysis showed that the phylogenetic tree constructed based on both nuclear and cpDNA were relatively similar, but a higher number of variable sites were observed in ITS compared to rpl32-trnL. The tree constructed by combined sequences could separate the species associated with the different sections, but could not separate the species in the sections. The results of this study indicate that the molecular data is in agreement with the morphological data reported in Flora Iranica at section level. However various populations of the different species in each section, except H. gorganicum, could not be distinguished from the others. The result suggests that more work is required for the taxonomic classification for the endemic Iranian species, including H. anisactis and H. rechingeri, as a separate species.