List of Articles Tubulin

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  1 - Generation of taxol susceptible yeast strain by inducing mutation TUB2 -Asp26
  Hamed Ashourion Shamsozoha Abolmaali Ziba Fooladvand Fatemeh Rezagholi
  Background & Objectives: Paclitaxel is an effective anti-microtubule agent against lung, ovarian and breast cancers. The low production of taxol in the yew, as well as its resistance to chemotherapy, is limiting the use of paclitaxel. This study aimed to create a sc More

  Background & Objectives: Paclitaxel is an effective anti-microtubule agent against lung, ovarian and breast cancers. The low production of taxol in the yew, as well as its resistance to chemotherapy, is limiting the use of paclitaxel. This study aimed to create a screening system for new sources of taxol using the taxol sensitive mutant strain of Saccharomyces cerevisiae.   Materials & Methods: To mutate the yeast chromosome TUB2 gene, primers containing a change in codon 26 from glycine to aspartic acid (GGT to GAT) were designed and TUB2-Asp26 gene amplified by three-step PCR method. The TUB2 gene was then cloned from the haploid strain into the yeast expression vector in the galactose promoter. After transplantation of haploid yeast with Gal-TUB2 construct (pZF58), transgenic screening was carried out for the second time by PCR product of the TUB2-Assp26 gene and in the medium containing galactose and against 40 μM taxol. Results: Of the 84 transgenes, the yeast strain YNAH1 was selected from the first screening and the integration of mutation in the chromosome was confirmed by the MBC value of 50 μM taxol. The formerly generated membrane-defective yeast strain with amino acid sequences similar to the brain beta-tubulin with an exception for amino acid 26, tolerated 25 µM taxol. However, in the present study, tolerance increased by up to 2-fold due to the use of yeast hosts that had no defects in membrane transporters. Conclusion: The mutant yeast strain can be used in screening to find new sources of taxol producers with production capacity up to 50 µM. Manuscript profile
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  2 - Study on genetic variation of Hyrcanian Calonectria pseudonaviculata (boxwood blight agent) isolates using RAPD and ISSR markers
  Parisa Khazaeli Saeed Rezaee Mansoureh Mirabolfathy Hamidreza Zamanizadeh Hadi Kiadaliri
  Background & Objectives: Boxwood tree is one of the Iranian endemic trees expanded throughout Hyrcanian forests. They are of particular importance among the world's forest reserves. Recently, Calonectria pseudonaviculata has been considered as one of the most import More

  Background & Objectives: Boxwood tree is one of the Iranian endemic trees expanded throughout Hyrcanian forests. They are of particular importance among the world's forest reserves. Recently, Calonectria pseudonaviculata has been considered as one of the most important causes of blight and leaf defoliation of the boxwood in Iran. For the first time, the present study was aimed to evaluate the genetic variation of Hyrcanian C. pseudonaviculata isolates using RAPD and ISSR markers. Material & Methods: In this study, 75 fungal isolates were collected from the infected boxwoods throughout Hyrcanian forests in the North of Iran. The isolates were assessed based on morphology and colony color. Genetic diversity of the isolates was studied using RAPD and ISSR markers. A part of the beta-tubulin gene was sequenced and deposited at NCBI. Phylogenetic analysis was carried out using PAUP* v. 4.0b10. Results: The colony color of isolates on potato dextrose agar (PDA) medium was brown with pale hale, conidia were cylindrical, rounded at both ends, 1-septate, 48- 68 µm. Stipe was long (90-14 µm) and hyaline, with the extension terminating in a broadly ellipsoid papillate vesicle, the widest part above the middle. Phylogenetic tree based on the β-tubulin gene showed that all isolates are placed into the same group. Our results indicated that the population of this fungus has a low genetic diversity in Iran. Conclusion: It seems that the variation of this pathogen is started to change genetically in some areas due to selection pressure phenomenon. Manuscript profile