Biomacromolecular Journal
Volume:5 Issue: 1, Summer 2019

Genome editing by engineered nuclease enzymes, which, induce DNA double strand break (DSB) followed by the activation of repair mechanisms, is of great importance to researchers in the field of biology and medicine. TALEN (Activator Transistor like Effector Nuclease) as a tool for genome editing is widely used in a variety of organisms and cells to study the role of genes or mutations in biological or pathological pathways, create model organisms or a therapeutic approach to single genetic disorders such as sickle cell anemia. TALE consists of: 1) N-terminal T3S signal, 2) Central tandem repeat domain, 3) C-terminal nuclear localization signal (NLS) and 4) Acidic transcriptional activation domain (AD, fused to a non-specific domain for DNA double strand break). DSB can undergo changes such as insertion, deletion, inversion, translocation through two major repair pathways of NHEJ and HDR. In this review article, we will first discuss the TALEN technology, assembly of custom TALEN and its transmission techniques. This is followed by studies on genome editing, various repair mechanisms and donor design in the HDR pathway. Finally, the applications of this technology will be discussed.

One of the most important reasons for dementia is Alzheimer's disease (AD) characterized by amyloid plaques and neuronal death. Using natural therapies has always been a great concern for AD. Herein, nerol, as a natural monoterpene, was applied to examine its protective and therapeutic effects on a rat model of AD. Fifty six Wistar, male rats were randomly assigned to 7 groups (n= 8 rats/group), including control group with no Aβ42 injections, group 2 with Aβ42 injection into rats’ hippocampus, group 3 with injection of phosphate buffer saline, as Aβ buffer, into rats’ hippocampus, group 4, 5, and 6 that received nerol at 30, 60, and 90 mg/kg, respectively, after being injected with Aβ42, and group 7 that received nerol (60 mg/kg) in a protective mode before Aβ injection. Behavioral, biochemical, and histological parameters were evaluated in all groups. Alzheimer’s-induced group showed impairment in lipid profile, antioxidant enzyme level, long-term memory, enzymes activity along with loss of neuronal cells. Treatment with nerol improved the lipid profile, antioxidant enzyme level, number of amyloid plaques, and memory function. Protection with nerol (60 mg/kg) also demonstrated similar improvements against AD. Hence, nerol has shown capability of improving the deficiency of neuronal cells, memory as well as antioxidant enzyme level associated with AD.

Gold nanoparticles are promising materials for biomedical applications because of the attractive optical properties such as the absorption and scattering of light at resonant wavelength. Due to the fruitful applications of gold nanoparticles (GNPs), they are appropriate for a variety of biological studies. One of the most important applications of nanoparticles which consist of transport of therapeutically relevant protein to in vivo or in vitro targets is protein carriers. Protein folding and properties of probable intermediates during the folding of proteins had been investigated in several studies. The molten globule state, a main intermediate of protein folding, has native-like secondary but perturbation of tertiary structure. Consequently, the influence of gold nanoparticles concentration on a model protein was studied at the buffer concentration by far- and near-UV circular dichroism (CD), Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), intrinsic fluorescence emission spectroscopy and 8-Anilino-1-naphthalenesulfonic acid binding. The results indicated that the interactions between gold nanoparticles and lysozyme lead to the formation of molten globule-like state.

Firefly luciferase is a monomeric enzyme of 62 kDa that catalyzes emission of green to yellow region, typically 550–570 nm upon reaction with d-luciferin, ATP, and molecular oxygen. Semiconductor nanocrystal, also known as the quantum dots (QDs), are nanoscaled inorganic particles in size range of 1-10nm. QDs have properties, such as sharp and symmetrical emission spectra, size-dependent emission, good chemical and photostability and high quantum yield. In this study, recombinant P. pyralis luciferase was expressd and then purified based on N -terminal His-tag. Then the effects of the Cadmium Tellurium QD(6.2nm) on the tertiary structure, kinetic properties, Bioluminescence Resonance Energy Transfer, thermal stability and remaining activity of luciferase was assayed using fluorescence spectroscopy and bioluminescence assay. The results showed that the CdTe QD affects the tertiary structure of the luciferase enzyme. The kinetic parameters of the enzyme also changed, as well as the thermal stability. The remaining activity was decrease in the presence of quantum dot compared to the native enzyme and BRET also was not observed in the presence of QD.

The process of skeletal muscle aging is linked to the development of age-related diseases such as metabolic syndrome, diabetes, cancer and Alzheimer’s disease. Hence, to further investigate the effect of Ursolic Acid (UA) endorses previous studies on skeletal muscle rejuvenation, we tested whether UA alters two prominent anti-aging biomarkers such as SIRT1 and SIRT6 in skeletal muscle. UA is a triterpenoid compound widely found in natural plants and fruits, with known effects on skeletal muscle. To conduct this experiment, UA dissolved in Corn Oil (200mg/ml) was administrated (200mg/kg IP injection) twice daily for 7 days to male aged-mice C57BL/6. Then, mice skeletal muscle tissues were isolated and proteins were examined through immunofluorescence microscopy. Our findings clearly illustrated that UA enhances SIRT1 (~3.5 folds) and SIRT6 (~4 folds) expression levels, p

Extensive use of methyl tert-butyl ether (MTBE) has raised significant threats to the environment through pollution of environmental resources including ground waters. This compound could accumulate in the blood stream through inhalation of contaminated air since MTBE has a high affinity for blood proteins. The interaction of blood proteins such as human hemoglobin (Hb) with MTBE results in conformational and likely functional changes. The main mechanism for harmful effects of MTBE on Hb is through production of reactive oxygen species (ROS). In this regard, the present work was proposed to study the possible antioxidant potential of two dietary antioxidant agents, curcumin and caffeine, on the reduction of MTBE damage on Hb. Different spectroscopic methods including fluorescence, UV-Vis, circular dichroism, chemiluminescence, and molecular docking were used to study the interactions of curcumin and caffeine with Hb in the presence of MTBE. Our results showed caffeine could decrease the aggregation and ROS effects of MTBE on Hb. However, in the presence of curcumin the MTBE mediated aggregation of Hb was enhanced. These opposing effects of curcumin and caffeine as antioxidants were mainly contributed to the high iron chelating activity of curcumin. Thus, the complex formation between curcumin and heme further enhanced ROS production capability of MTBE.

Kinetic of the photo-oxidation of phenol in aqueous alkaline and neutral buffer solutions was studied and compared by irradiation of visible light in the presence of tetra-cationic porphyrins and their zinc metal ion photo-sensitizers. The porphyrins 5,10,15,20-tetrakis(3- methylpyridinium)porphyrin (TMPyP(3)); 5,10,15,20-tetrakis(4-methylpyridinium)porphyrin (TMPyP(4)); 5,10,15,20-tetrakis(4-N,N,Ntrimethylanilinium)porphyrin (TAPP) and their zinc ion complexes were used in this study. In the dark conditions, none of the porphyrin compounds showed any effect on the reducing of phenol. The results showed that the rate of the photo-oxidation of phenol in alkaline medium has been increased in the presence of these photo-sensitizers. Among them, the rate of photo-oxidation by TAPP was more than the other ones. In neutral medium, the rate of the photo-oxidation of all of the compounds have been shown approximately similar behavior. It was found that the dominant pathway of phenol degradation occurred in the reaction with molecular singlet oxygen (1O2). Kinetic parameters of the phenol reaction with 1O2 were estimated. According to the equation (lnA/A0 = kobs t) and by plotting lnA/A0 against time, the rate of the reaction was obtained first order.