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Thirty eight ecotypes of watermelon were collected from different parts of Iran. After the preparation of the field, these eotypes were cultivated in a completely randomized block design with three replications. In order to invest-igate genetic diversity, genomic DNA samples were extracted from leaves and Polymerase chain reactions were optimized using 14 SRAP primer pairs. One hundred thirty six polymorphic bands were detected, of which the EM10-Me4 was the most abundant primer pair with 19 bands and EM16-Me4 and EM16-Me14 were the least primer pairs with 7 bands. PIC index varied from 0.20 to 0.32 and genetic diversity was 0.17 to 0.28 on the basis of Nei index. Fisher's Linear Detection Analysis showed that the UPGMA method and the grouping accuracy of about 90% are more appropriate than other cluster analysis methods. Cluster analysis, using Jakard method, was performed and the ecotypes studied were classified into five distinct groups. Based on the PCA, the first and second components included 92.5% of the variation, which represents the proper distribution of the markers on the whole genome.

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Plant growth is greatly influenced by environmental stresses including water deficit, salinity and extreme temperatures. Therefore, the identification of genes, especially regulatory ones whose expression enables plants to adapt to or to tolerate these abiotic stresses, is very essential. MYB proteins, a superfamily of transcription factors, play regulatory roles in developmental processes and in defense responses in plants. Members are characterized by a structurally conserved DNA-binding domain, i.e., the MYB domain. Thus, a factorial experiment in a randomized complete block design with three replications was carried out to investigate the effect of different levels of drought stress on the relative expression of TaMYB73 transcription factor gene using Real Time PCR method at Biotechnology Research Institute of Zabol University. The experimental treatments included durum wheat genotypes (Shabrang, Behrang, Karkheh, Aria and Dena) and drought levels (5, 10, 15, 20 and 25% of field capacity). Seedlings of genotypes
were cultured in pots and drought stress was exerted after 45 days (four to five leaves). Data analysis was performed using Ratio =2 ^-ΔΔCT and SAS software version 9.1. The results of the 2-way ANOVA for the effect of genotype, drought stress and cross-effects of drought stress on the relative expression of TaMYB73 gene and the amount of osmotic regulators (Proline and Carbohydrate) at different stress levels (20, 15, and 5% of field capacity) were significant in comparison with the normal condition (25% of field capacity) at 1% probability level. With the increase of drought stress level from 5 to 20% of crop capacity, relative to the normal level (25% crop capacity), the relative expression of TaMYB73 gene and osmotic regulators of proline and carbohydrates increased in Beharang, Karkheh and Dena genotypes. Therefore, Karkheh and Dena genotypes showed greater resistance to drought stress among the 5 genotypes studied.
 

 

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Yersinia pestis, a gram-negative rod belonging to the Enterobacteriaceae family, is the causative agent of plague. Classical methods of detecting the organisms are time-consuming, expensive and dangerous. The aim of the study was to design a Real-time PCR assay on the basis of the pla gene of Yersinia pestis. In this research the Real- time PCR test was optimized by using special primers for targeting pla gene. After preparing 10-fold serial dilutions of the pla and their analysis by the assay, the last dilution showing a fluorescent signal was confirmed as the limit of detection (LOD). A standard curve based on the Ct values was depicted, so the assay was developed to quantify the target gene. The analytical specificity was determined by subjecting the genome of some control negative bacteria to the assay. In this experiment, negative control genomes did not show detectable signals in the assay. The last dilution of pla plasmid which showed a fluorescent signal was 4.5 fg. So, the lower detectable copy numbers of the gene in a 20 μl PCR reaction was calculated as 1×10³.
 

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Q fever is caused by Coxiella burnetii and is transmitted by more than 40 tick species. This study aimed to identify the tick species in goats of Meshkin-Shahr, Ardabil Province, Iran, and their role in the transmission of C. burnetii. A number of 365 goats were inspected for the infestation of hard ticks in a randomized sampling design, during a 1-year period from April 2013 to April 2014. A total number of 280 tick specimens were collected and identified and were then examined by molecular methods for the presence of C. burnetii infection. 40.8% of the infected animals had at least one species of tick. The goats which were studied were found to be infested by the following tick species: Hyalomma anatolicum anatolicum (33.9%), Rhipicephalus sanguineus (22.1%), Rhipicephalus turanicus (17.1%), Hyalomma excavatum (11.1%), Rhipicephalus bursa (5%), Hyalomma detritum (3.9%), Hyalomma dromedarii (3.6%), Hyalomma asiaticum asiaticum (1.8%), and Hyalomma marginatum (1%). There were no significant differences between the infestation rate in different seasons, genders and ages of the animals which were studied (p=0.05). The molecular assay of 280 tick specimens revealed the presence of C. burnetii infection in 5 out of 40 pool samples (6-8 tick individuals of the same species in each pool), including H. anatolicum anatolicum (3 pools), H. excavatum (1 pool) and R. sanguineus (1 pool). The present study, therefore, reports the rate of C. burnetii infection transmitted by hard ticks in North-West of Iran for the first time. According to the zoonotic aspect of Q fever, further studies on the carriers as well as other hosts of the infection were found to be necessary.

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Urmia Lake is the largest lake in the Iranian plateau and the second largest Salt Lake in the world. This study was conducted to identify hypersaline bacteria in the lake through the screening with molecular markers. For the molecular study of the bacterial microbiome of the lake, samples were collected from water, sludge and soil of the different parts of the lake during different seasons of 2018 and 2019, and then transferred to the laboratory under standard conditions. Bacterial isolates were purified from the samples using universal culture media. ERIC molecular marker was used to study the species diversity. After clustering analysis of the species on the basis of their genetic markers, one bacterium from each cluster was selected as the representative of each cluster and then identified by DNA barcoding method using the 16srDNA. Biochemical tests were performed to confirm the molecular results. In total, 102 bacterial isolates were isolated and purified from the samples, of which only 29 isolates were extremely-halophilic. The molecular diversity of isolates, based on ERIC molecular marker, showed that isolates can be assigned to five different clusters. Five isolates selected from each cluster were selected and their 16SrDNA region were amplified and sequenced with 16SrDNA-specific primers. The results showed that the five selected isolates with 99% similarity belonged to the species Microbulbifer halophilus, Halomonas salina, Bacillus sonorensis, Salinivibrio costicola and Bacillus aquimaris. The results of molecular identification were consistent with the results of biochemical tests.
 
 

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Pancreatic cancer is one of the most deadly and aggressive cancers; Fluorouracil induces apoptosis and cell cycle arrest in cancer cells. In the present study; the effect of Fluorouracil on different stages of the cell cycle and the expression of genes involved in the internal pathway of apoptosis in the AsPC-1 cell line (human pancreatic cancer) were investigated. In order to do so, MTT assay was used to evaluate the cytotoxic effect of Fluorouracil on AsPC-1 cell proliferation; The type of induced cell death and cell cycle changes were investigated by flow cytometry; changes in the expression level of genes (BAX, Bcl-2, APAF-1, Caspase-3, Caspase-9, p53, p21) were examined by Real-time PCR. Quantitative data were analyzed at the significant level of (p<0.05). The MTT assay results showed that Fluorouracil decreased AsPC-1 cell proliferation in a concentration-dependent manner. The results of flow cytometry analysis showed that increased percentage of apoptotic cells in the treated cells; Fluorouracil induces S phase cell cycle arrest in AsPC-1 cells and reduced distribution in the G1 phase. The Real-time PCR results in treated cells showed an increase in the expression of genes in the mitochondrial apoptotic pathway as well as genes effective in regulating the cell cycle. Fluorouracil reduces cell proliferation and induces apoptosis by increasing the expression of genes involved in the Intrinsic apoptotic pathway in AsPC-1 cells; Fluorouracil also caused cell cycle arrest in these cells by regulating the (p53, p21) genes.