فهرست مطالب m.r. mofid

Kinome refers to the complete set of protein kinases encoded in the genome. The most common type of post-translational modification is phosphorylation, with more than two-thirds of all human encoded proteins being phosphorylated by protein kinases. Phosphorylation as an important regulatory factor in the activity of proteins greatly expands the flexibility of the epigenome. Thus, protein kinases often promote cell proliferation, survival, and migration by participating in intracellular pathways and are associated with carcinogenesis when overexpressed or activated. The main goal of this study is to investigate the role of kinase enzymes in causing cancer and to investigate their potential as drugs in the treatment of various types of cancer.

In this review, by searching Scopus, PubMed, Web of Science and ScienceDirect databases, articles published between 2010 and 2022 were selected and analyzed using the keywords "cancer, human kinome, kinase and kinase inhibitor".

64 articles were selected according to the research topic and 11 articles were excluded due to the lack of relation to the main keywords. In this study, the role of kinases in cell proliferation and human cancers has been investigated, and kinase inhibitors in combination with other common treatments such as chemotherapy or radiation therapy can be mentioned as a new and promising approach in cancer treatment.

Based on the results of this study, kinases are known as one of the most important components of cell growth and proliferation, so that they play an important role in the cancer process with excessive activity. This study shows that controlling and inhibiting the kinase family to overcome cancer cell growth has good benefits.

The isolation of the target protein from inclusion bodies (IBs) is a preliminary step to increase protein titer and to maintain its biological activity. In the present study, the effects of various cell lysis methods and the expression temperature was investigated on the improvement of the subsequent purification steps of mecasermin produced in IB. We also investigated the solubilization profile of the top-notch IB in 6 M guanidine hydrochloride (Gdn-HCl) and 8 M urea at different pH ranges. Mecasermin was expressed at various temperatures (25, 28, 30, and 37 °C) and the Escherichia coli cells were lysed by different cell lysis methods. The purity and quality of harvested IBs was evaluated with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Finally, mecasermin was refolded and purified using gel filtration chromatography. The profile of SDS-PAGE analysis showed higher quality and purity after application of sonication coupled with lysozyme pretreatment for expressed mecasermin at 37 °C. Besides, from dithiothreitol application in washing step, we achieved a manifold enriched secondary IB for further purification of mecasermin. Mecasermin exhibited optimized solubility in 6 M Gdn-HCl at pH of 5.4. The findings of this study indicate an important role for cell disruption techniques to efficient purification of mecasermin. The study presents the most efficient techniques for improvement of downstream purification of mecasermin.

Human Insulin-like growth factor 1 (hIGF-1) consists of 70 amino acids in a single chain with three intermolecular disulfide bridges possessing valuable therapeutic effects. To date, numerous variants of specifically engineered hIGF-1 have been produced so as to improve hIGF-1 biological activity, stability and stronger binding to IGF-1 receptor. Mecasermin is one of the modified variants with one amino acid substitution near the N-terminal (T4I) approved for the treatment of growth failure diabetes, wound healing, amyotrophic lateral sclerosis and severe primary IGF-1 deficiency. No scientific report for recombinant production of mecasermin in Escherichia coli (E. coli) expression system has been sofar reported. In the present study, we therefore investigated the overexpression of mecasermin in two different E. coli strains in order to obtain higher yield of recombinant protein. To achieve this goal, mecasermin DNA encoding sequence was designed based on polypeptide sequence, optimized according to E. coli codon preference, and cloned in pET15b. Recombinant vector, pET15-mecasermin, transferred into two E. coli strains rigami B (DE3) and BL21 (DE3) and induced for expression in a small scale. Results revealed the E. coli Origami B (DE3) expression system was a preferable host for mecasermin production due to its high expression level being around twice as much as BL21 (DE3). Large scale mecasermin production was performed in batch culture and produced recombinant protein specifically confirmed by western blotting and mass spectroscopy. Since major part of recombinant mecasermin was expressed as inclusion body, isolation and refolding was accomplished through developed purification procedure, and finally recombinant protein was successfully purified by gel filtration chromatography.

Due to the widespread applications of xylitol dehydrogenase, an enzyme used for the production of xylitol, the present study was designed for the cloning of xylitol dehydrogenase gene from Glcunobacter oxydans DSM 2003. After extraction of genomic DNA from this bacterium, xylitol dehydrogenase gene was replicated using polymerase chain reaction (PCR). The amplified product was entered into pTZ57R cloning vector by T/A cloning method and transformation was performed by heat shocking of the E. coli XL1-blue competent cells. Following plasmid preparation, the cloned gene was digested out and ligated into the expression vector pET-22b(+). Electrophoresis of PCR product showed a 789 bp band. Recombinant plasmid (rpTZ57R) was then constructed. This plasmid was double digested with XhoI and EcoRI resulting in 800 bp and 2900 bp bands. The obtained insert was ligated into pET-22b(+) vector and its orientation was confirmed with XhoI and BamHI restriction enzymes. In conclusion, in the present study the recombinant expression vector containing xylitol dehydrogenase gene has been constructed and can be used for the production of this enzyme in high quantities.

Ergovaline, the main ergopeptine alkaloid produced in tall fescue (Fescue arundinacea Schreb.) infected with endophyte (Neotyphodium coenophialum Morgan- Jones & Gams), is known to cause tall fescue toxicosis. This study was conducted to examine the presence of fungal endophytes in five populations of tall fescue collected from various regions of Iran. The existence of Neotyphodium mycelia in the tissues of the samples was confirmed by microscopic examination, and the isolation was performed from leaf tissues of the hosts on potato dextrose agar. All isolates were confirmed as the Neotyphodium species by PCR, using specific primers. Mass detection and determination of ergovaline were performed by HPLC at three plant growth stages. Ergovaline was detected in all isolates, with the mean concentrations of 0.24 to 3.48 µg/g dry matter of different populations for the whole three plant growth stages. The differences in ergovaline content between plant populations and sampling time were statistically significant. This is the first report of ergovaline content in endophyte infected Fescue. arundinacea from natural grasslands in Iran.