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Background and Objective: Human erythropoietin (EPO) is a glycosylated hormone with molecular weight of about 40 KDa which is synthesized in kidneys and plays an important role in proliferation and differentiation of erythrocytes.This study was done to assess and analyze the expression of recombinant EPO in Leishmania tarentolae host. Method: In this descriptive study, the EPO gene was codoned , optimized with bioinformatics database prior to be synthesized. It was cleaved by KpnIandXbaI enzymes and cloned into pLEXSY expression vector. The constructed expression cassette was transfected into Leishmania tarentolae through electroporaton method. Identification and confirmation of transfected colonies was performed using PCR expression diagnostic primers and EPO specific primers. Induction of the cloned gene was done with tetracycline. The expression in induced strains was analyzed by SDS-PAGE and western blotting techniques. The amount of recombinant protein was quantified by ELISA method. Confirmation of cloning and EPO expression cassette was carried out through genetic engineering procedures. Results: Expression analysis of transfected parasitic strain with SDS-PAGE and western blotting confirmed gene integration into chromosomal of host as well as expression. The optimal conditions for expression were found to be 10μg of tetracycline and 72h induction time. Molecular weight of expressed protein estimated to be 40 KDa and expression level was determined to be 12.4 mg/l which was equal to 1% of total protein mass. Conclusion: EPO expression cassette for cloning and expression in Leishmania tarentolae was designed and protein of interest was successfully induced and identified Leishmania tarentolae can be used as a suitable host for production of recombinant EPO and this technology has a potential for localization.

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Background and Objective: Neural, hormonal, and mechanical factors regulate the expression of fast-twitch isoforms in developing and mature muscle fibers. The transcriptional mechanisms responsible for regulating the gene expression of myosin heavy chain types are not well understood. This study aimed to determine the effect of a single session of intense resistance exercise with glutamine supplementation on the relative expression of the alpha and IIX isoforms of the myosin heavy chain gene in male rats.
Methods: This experimental study was conducted on 30 adult male Wistar rats divided into three groups: control, intense resistance exercise (first experimental group), and fierce resistance exercise combined with glutamine supplementation (second experimental group). The exercise groups participated in a single session of resistance climbing on an inclined plane with 4 sets of 5 repetitions, 30 seconds of rest between repetitions, and 2 minutes of rest between sets. Glutamine supplement powder was dissolved in 100 ml of distilled water at a dose of 0.5 grams per kilogram of body weight and administered daily via gavage for 5 days. The expression of alpha and IIX isoforms of the myosin heavy chain gene was examined in the extensor digitorum longus muscle tissue.
Results: The relative expression of the alpha myosin heavy chain gene in the fast-twitch muscle fibers increased significantly in the first experimental group (1.93±0.298) and the second experimental group (1.65±0.195) compared to the control group (P<0.05). The relative expression of the IIX motor unit gene in the fast-twitch muscle fibers also increased significantly in the first experimental group (1.42±0.239) and the second experimental group (1.26±0.190) compared to the control group (P<0.05). The increase in the relative expression of the alpha myosin heavy chain gene in the first experimental group compared to the second experimental group was statistically significant (P<0.05). However, the increase in the relative expression of the IIX motor unit gene in the first experimental group compared to the second experimental group was not statistically significant.
Conclusion: Our study concludes that a single session of intense resistance exercise, with or without glutamine supplementation, significantly increases the relative expression of the alpha myosin heavy chain gene and the IIX motor unit gene in the fast-twitch muscle fibers of the extensor digitorum longus muscle in adult male rats. These findings provide valuable insights into the molecular