Over the past decade the variety of hosts and vector systems for recombinant protein expression has increased dramatically. Researchers now select from among mammalian, insect, yeast, and prokaryotic hosts, and the number of vectors available for use in these organisms continues to grow. With the increased availability of cDNAs and protein coding sequencing information, it is certain that these and other, yet to be developed systems will be important in the future. Despite the development of eukaryotic systems, E. coli remains the most widely used host for recombinant protein expression. Optimization of recombinant protein expression in prokaryotic and eukaryotic host systems has been carried out by varying simple parameters such as expression vectors, host strains, media composition, and growth temperature. Recombinant gene expression in eukaryotic systems is often the only viable route to the large-scale production of authentic, post translationally modified proteins. It is becoming increasingly easy to find a suitable system to overexpress virtually any gene product, provided that it is properly engineered into an appropriate expression vector.

The purpose of this study was to explore the different roles of heat shock proteins especially in immunity and infections. Heat shock proteins were discovered 56 years ago, and much of the work has focused on the role of these proteins that play in protecting cells from stress. Heat shock proteins are highly conserved class of proteins present in all species from bacteria to humans. Several experimental studies have been successful in pointing to the role of heat shock protein as a clinical biomarker and therapeutic target in a variety of diseases. It will also highlight features of HSP family, and will discuss future implications of HSPs in the diagnosis and prognosis of clinical and therapeutic significance. The development of membrane-interacting drugs that modify specific membrane domains, modulating heat shock response, may also be of significant therapeutic benefit. These proteins function as molecular chaperones, assisting in the refolding of misfolded proteins or their elimination if they become irreversibly damaged. Proteomic studies have identified several different HSPs in various disease types that may be clinical biomarkers or molecular targets for various therapies.

The evolutionary constraints of a gene consist of cis-gene regulatory regions, such as promoters and enhancers, which contribute to the regulation of gene expression. Several genomic and computational studies stated the roles of G-quadruplex and i-motif structures in vital cellular processes like transcription, translation, gene regulation, etc. The formation of these non-B DNA structures is supported by the occurrence of unique repeated sequences. However, many studies lean toward understanding the role of the G-quadruplex, and only recent studies indicated i-motif significance. In this study, we attempted to dissect the enrichment of G-quadruplex and i-motifs in promoter regions of mammals and plants. To this end, we employed the genomic sequences encompassing -500 to +500 region relative to the gene start positions in mammals and plants retrieved from the UCSC browser and Plant Genome database (PlantGDB). We computed the putative G-quadruplexes and i-motifs with well-recognized regular expression sequence patterns. We observed that G-quadruplex motifs showed preponderance in mammals, algal species, namely, green algae, and Chlamydomonas when compared to plants. Contrastingly i-motifs are enriched in both monocot and dicot plants compared to G-quadruplex motifs. The comparative examinations in this study revamp our understanding of the two quadruplex structures and their emerging functional roles in complex eukaryotes.

Bone tissue engineering has been an evolving field for decades in view of its intrinsic potential to regenerate and the necessity of repair in response to injuries or disorders. Scaffold implantation is one of the most applied techniques to overcome the donor crisis leading to bone regeneration using osteoinducible cells. Numerous combinations of scaffold composites are being designed in-order to achieve the maximum regeneration considering the parameters such as bio-compatibility, biodegradability osteo conductivity, mechanical strength and hydrophilicity that helps in the assessment of the possible negative impacts of the healing process. This review article concentrates on some of such composites where the chitosan, a natural polymer, is combined with the other biopolymers like synthetic and ceramic polymers at various concentrations and treatments reporting the desired results. The distinct characteristic of this review is that it focuses on the scaffolds that are completely Nano fibrous in nature fabricated by electro spinning. In this review, we reported the results of various combinations of chitosan and their significance. The ability to form (Calcium and Phosphate crystals-Biomineralization) is evident that chitosan combined with the other biopolymers can be contemplated as phenomenal scaffold as the used seed cells are clinically applied across the world – human mesenchymal stem cells (hMSCs), bone marrow mesenchymal stem cells (BM-MSCs), mouse mesenchymal stem cells (mMSCs), human fetal osteoblasts (hFOB), etc. Apart from the in-vitro studies, the results of in-vivo experiments were also included in this article where the implantation targets the calvarial bone regeneration. Besides osteogenic differentiation, this article highlighted the prominent efficiency of the scaffolds to exhibit the antimicrobial activity and to act as drug delivery system when doped with components like AgNO3, Chlorhexidine, ZnO and Amoxicillin, Sinapic acid respectively. Overall, in the current review, we tried to focus on consolidation of various results related to chitosan based nanofibers for bone tissue remodeling.