Rxi Pharmaceuticals Corp (RXII)

 

The genome is made of a double-strand of DNA (the double helix) that acts as an instruction manual for the production of the roughly 30,000 to 50,000 human proteins. Proteins are important molecules that allow cells and organisms to live and function. With rare exceptions, each cell in the human body has the entire complement of genes. However, only a subset of these genes directs the production of proteins in any particular cell type. For example, a muscle cell produces muscle-specific protein, whereas a skin cell does not.

 

In order for a gene to guide the production of a protein, it must first be copied into a single-stranded chemical messenger (messenger RNA or mRNA), which is then translated into protein. RNA interference is a naturally occurring process by which a particular messenger RNA can be destroyed before it is translated into protein. The process of RNAi can be artificially induced by introducing a small double-stranded fragment of RNA corresponding to a particular messenger RNA into a cell. A protein complex set of proteins within the cell called RISC (RNA-Induced Silencing Complex) recognizes this double-stranded RNA fragment and splits the double-strands apart, retaining one strand in the RISC complex. The RISC then helps this guide strand of RNA bind to and destroy its corresponding cellular messenger RNA target. Thus, RNAi provides a method to potentially block the creation of the proteins that cause disease, as depicted in the following figure.

 

The human genetic code (human genome) is made of a double-strand of DNA (the double helix) that acts as an instruction manual for the production of the roughly 50,000 human proteins. Proteins are the molecular parts that allow cells and organisms to live and function. With rare exceptions, each cell in the human body has the entire complement of genes. However, only a subset of these genes directs the production of proteins in any particular cell type. For example, a muscle cell produces muscle-specific protein, whereas a skin cell does not. In order for a gene to guide the production of a protein, it must first be copied into a single-stranded chemical messenger (messenger RNA) and then translated into protein. RNA interference (RNAi) is a naturally occurring process by which a particular messenger RNA can be destroyed before it is translated into protein. The process of RNAi can be artificially induced by introducing a double-stranded fragment of RNA corresponding to a particular messenger RNA into a cell. A complex set of proteins within the cell called RISC (RNA-Induced Silencing Complex) recognizes this double-stranded RNA fragment and splits the double-strands apart. One of the strands of RNA then binds to its corresponding cellular messenger RNA and destroys this targeted RNA. Thus, RNAi provides a method to potentially block the creation of the proteins that cause disease, as depicted in the following figure.