Gene Silencing – BioQuakes

CRISPR/Cas9 is currently being researched as a method to alter genes by editing or silencing them. This enzyme is derived from bacteria and archaea that use it to protect themselves from viruses. Researchers are currently finding more practical applications for this discovery. However, it has been recently been found that nucleosomes may play a large effect on CRISPR.

Structure of a Nucleosome

At UC Berkeley, researchers have been studying the interaction of these prokaryotic enzymes with eukaryotic cells. They have found that nucleosomes may inhibit CRISPR/Cas9. Because bacteria likely do not use this enzyme to explore eukaryotic chromatin structures, their enzymes are not adapted to these types of structures. This is seen by many of the researchers’ experiments where stretches of DNA with low concentrations of nucleosomes had higher activity of CRISPR while others stretches with high concentrations of nucleosomes had lower activity. Scientists have also added chromatin remodeling enzymes while using CRISPR and found higher activity.

This has a few implications on the usage of the enzyme. While gene editing may be less influenced because only one cut is needed to introduce a sequence, scientists should take nucleosome concentration into account in gene silencing and epigenetic editing. CRISPR/Cas9 is an amazing discovery for genetics but we still have much to learn about how it works and how we can use it.

Original Article

In today’s world, there are more and more breaks in cancer research, and Dr. Sven Diederichs and his team are one more to add to the list. Dr. Sven believes that “In many cancers we find that specific non- coding genes are particularly active. Therefore, we want to understand what the RNA molecules transcribed from these genes bring about in the tumor cells.” Could this be the big answer? After all this time, could it be that it has been RNA molecules sending messages that create cancer.

Dr. Sven and his team came to this hypothesis and therefore created a method to find out the truth called “loss-of-function.” In this experiment, scientists can silence a gene of a living cell and try to find changes in the cell’s behavior, metabolism, or physiology. They created this method on the use of zinc finger nucleases.

Once the scientist figured out how to make this method work, they were able to, for the first time, completely silence genes. Why is this important to cancer research? Dr. Sven believes that certain genes play a huge role in the development of cancer and are very active in tumor cells. If we have the chance to “shut down” these genes in RNA before they become active, we can ultimately prevent cancer.

In AP Biology class, we are learning about RNA transferring different kinds of information that stimulate cells to perform certain functions based on need, location and ability. Are all these stimuli good? Or are they sending messages to create tumor cells?

We all know someone that has cancer, whether it’s your brother’s girlfriend’s uncle’s high school girlfriend, a friend of a friend, your best friend or it’s you. Everyone has a reason they want to get rid of such a terrible disease. So would you invest in this research or do you think its impossible to figure out which exact gene is the cause for all cancers?

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: Gene Silencing

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