RNAi (known as RNA interference) is a process through which cells control the activity and expression of particular genes. Small RNA molecules such as siRNA and miRNA are vital for inducing the RNAi process. In this mechanism, siRNAs and miRNAs bind to their complimentary RNAs and regulate their activity by preventing messenger RNA (mRNA) from engaging in protein production. This process plays an important role in the cell’s ability to defend itself against viruses, and may help researchers and scientists develop gene expression systems that can prevent or cure many disease processes.
Gene regulation or gene knockdown is useful for many research applications, including gene target discovery, validation of gene targets, functional analysis of genes, assay development and screening of therapeutic compounds. Understanding of gene regulation has the promise to elucidate cellular mechanisms and treat diseases that are resultant of misregulation of proteins and viral diseases. The use of RNAi-inducing species in vivo for research purposes and in therapeutic development is under investigation by a number of biotechnology companies. One hurdle they have encountered is that nucleic acid based products, including siRNA and gene constructs to manufacture shRNA, are notoriously difficult to deliver, and often excreted by the cell prior to providing effectiveness. DNA is vulnerable to nucleases in both blood and the gastrointestinal system, with solutions to bioavailability being a productive area of investigation. Improvements of delivery include using liposomal formulations, nanoparticles, viral vectors and applying modifications to the nucleic acid mimic.
A typical RNAi research services laboratory offers cloning of short hairpin RNA (shRNA) into a suitable vector backbone, and then creates a stable expressing cell line in which the plasmid construct integrates into the genome and expresses an antibiotic resistance gene for clonal selection. The resultant cell line can then be utilized in functional RNAi validation experiments.
Commercial RNAi services often includes the ability to express double-stranded RNA (dsRNA) in vitro and in vivo to stimulate cellular processes or actions that reduce the expression of specific genes (such as oncogenes). The ability to inhibit or knockdown gene expression in cells is achieved using the process of plasmid DNA transfection as mentioned previously or through the transfection of small interfering RNA (siRNA). In either case, one must be careful to not induce an antiviral response, which is an essential consideration in the development of novel therapeutics and treatment protocols.
The advances in stable cell line creation has enabled scientists and researchers to accelerate stable cell line creation to roughly 4-5 weeks, whereas previously it took 30 or 40 weeks to complete. RNAi gene silencing experiments rely heavily on high transfection efficiencies as well as high cell viability. Utilizing commercial RNAi services avoids unsuccessful experiments along with the undesired waste of time and money. Various bioscience providers throughout the world offer RNAi services, along with pre-optimized siRNA/DNA transfection reagents.
Biology CRO pre-clinical research services include:
- IC50 pharm/tox testing
- xenograft animal studies
- RNAi services
- siRNA and protein liposome encapsulation
- in vivo siRNA delivery and tissue-targeting
- generation of stable cell lines in 28 days
- inducible RNAi cell line development
- cell banking and cryopreservation GLP-compliant services
- RNAi and biodistribution research studies
Commercial RNAi services are able to provide highly efficient transfection methods, healthy cultures and optimal conditions for stable transfection, as well as high quality materials to ensure a greater chance of success. If needed, development of retroviral vectors allows a capability to transform single-stranded RNA (ssRNA) genomes into double-stranded DNA molecules that enable stable integration into host genomes. Such gene transfers, as well as services like multiplex protein assays, recombinant RNA or protein production will help the efforts of scientists and researchers to create novel medicines and treatments.