جستجوی مقالات مرتبط با کلیدواژه « rt-pcr » در نشریات گروه « زیست شناسی »

Drought is one of the most important abiotic stresses that affects the growth and development of plants. Adaptation of the plants to abiotic stresses causes changes in the expression of a large number of defense genes and their regulators, including transcription factors. MYB proteins are a large family of transcription factors that are of particular importance in regulating developmental processes and defense responses in plants. In this study, the expression level of eight MYB transcription factors from bread wheat in Tajen and Zagros cultivars was investigated in response to drought stress. RT-PCR analysis showed that almost all genes of the MYB family, including TC282418, TaMYB80, PTTa00740, TaMYB33, TaMYBR3, were expressed with 2.4, 3.2, 7.1, 6.1, and 6.6 respectively, had an increased expression compared to the control under severe stress in the Zagros genotype that was examined in this research. On the other hand, the Zagros variety, which is one of the drought stress-tolerant varieties, had a higher expression increase than the Tajen variety for all the studied genes.

Flagella and motility are important factors in bacterial colonization and pathogenicity. flaB is one of the important genes encoding the flagellar protein, which produces antibody against this gene play major role in immunogenesis. The aim of the present study was to make a flaB gene construct and to evaluate its expression in eukaryotic cells as a candidate for vaccine production. 

flaB cloning and subcloning was done in pTZ57RT and pBudCE4.1 plasmids. Then the accuracy of the obtained clones confirmed by PCR, double enzyme digestion and sequencing. After transferring the confirmed gene construct to the animal cells, the gene expression was checked at the level of transcriptome and proteome by RT-PCR and SDS-PAGE methods. 

PCR results showed amplification of a1563 bp segment related to flaB gene. Desired gene cloning had confirmed by PCR, double enzyme digestion and sequencing. The observation of 1563 bp and 56 kDa bands from RT-PCR and SDS-PAGE indicates the successful expression of flaB in HDF cells.

The recombinant gene construct can express the FlaB protein in animal cells. Therefore, according to the results, this construct can be used as a candidate to produce an effective gene vaccine against Helicobacter pylori.

The transition to flowering is a major phase change in life cycle of plants. Flowering locus T (FT) gene is the final signaling target gene of the photoperiod pathway that promotes flowering. FT protein is a major component of flowering hormone (florigen). This study was performed to identify FT homologus gene in garden cress (Lepidium sativum L.). Total RNA was isolated from young leaf tissues of L. sativum in reproductive phase and was used for first-strand cDNA synthesis. The specific primers were designed based on nucleotide sequence alignment of FT homologus genes from other plants and were used in RT-PCR. The RT-PCR product were purified and sequenced. The results indicated amplification of 294 nucleotides fragment that was named LsFT and registered in NCBI database with access number KP070729. This part of FT gene codes major part of phosphatidyl ethanolamine-binding Protein (PEBP) domain of FT protein that is conserved in amino acid sequence in many plants. Comparison of this deduced protein with FT homologous proteins from other species showed %61 to %94 identity. According to these results, LsFT can play a similar role as FT in flowering induction and could act as a flowering inducer gene in Lepidium sativum L.

Growing faster and mass production of seed is always notable economically, industrially and pharmaceutically. Hence, the identification of the effective genes in growth, flowering and seed production is very valuable in the plants. The CURLY LEAF (CLF) is a key gene due to its important role in flowering inhibition. In this research, identification of CLF gene in black mustard (Brassica nigra L.), due to pharmaceutical and industrial consumption and its proximity to Arabidopsis model plant, was studied. For gene identification studies, the total RNA was extracted from the mature leaves in the vegetative stage. Gene expression was studied using extracted RNAs from leaves and shoot tips in both vegetative and generative stages as well as flower buds. Identification and expression were investigated after cDNA synthesis using the designed primers and the RT-PCR technique. The results confirmed a specific fragment of 665 nucleotides recorded in the gene bank as bnCLF (KT984485). The studies of phylogenetic tree showed that the CLF gene of the black mustard has a close relation with Brassicaceae family but the most homology was observed with Brassica rapa. The higher expression of CLF was observed in leaf and shoot tip at generative phase compared with vegetative phase. Further, the highest of expression amount was seen in floral buds in generative phase than leaf and shoot tip. Therefore, it seems that it is possible to accelerate flowering in some plants by identification and repression of this gene.

Newcastle is an acute and contagious disease in poultry that has irreparable economic detriments in the poultry industry. Due to many deaths in broiler chicken flocks, it is vital to detect and characterize the viral circulation. The aim of this study was to isolation and pathotyping of Newcastle virus by RT-PCR and MDT (Mean death time) methods in broiler chickens in Fars province.

In this study 300 tracheal tissue and cloacal swab samples from 30 infected poultry farms with a high mortality and respiratory disease were collected in Fars province. The samples were inoculated in  the allantoic cavities of 9-11-day-old embryonated chicken eggs. After 72 hours incubation, the allantoic fluids were tested by hemagglutination, RT-PCR and MDT methods for the present of Newcastle virus and their pathotyping.

10 out of total samples investigated by molecular method showed a 535bp amplification band fragment and were identified as Newcastle viruses. Also, among these samples, Velogenic, Mesogenic and Lentogenic strains identified in 6, 3 and 1 sample respectively by MDT method.

Based on isolation of velogenic and mesogenic viruses in broiler chickens flocks, it is essential to continues survey vaccine strains and their effectiveness.