Grant: Project Grant

Messenger RNAs (mRNA) are copies of genes that contain the information necessary to produce proteins. They are first made as premature (pre) mRNAs and must undergo a process called splicing to become the mature mRNAs that are used to produce proteins, which are the building blocks of our cells. Genetic disorders are caused by rare spelling errors in our genes that are copied into the pre-mRNA. Some of these spelling errors lead to defects in splicing. Depending on the type of splicing defect, the disease symptoms can be milder or more severe. The type of splicing defect can also determine which type of treatment could be beneficial. However, predicting the type of splicing defect can be challenging. Human pre-mRNAs are very long, but splicing has only been studied for one short section of a pre-mRNA at a time. Our project will use new technology that allows to read much longer sections of pre-mRNAs. We will initially focus on collagen VI-related muscular dystrophy, a childhood-onset muscle disease that is caused by spelling errors in the COL6A1-3 genes and for which there is currently no cure. We will investigate the order in which splicing happens in the COL6 pre-mRNAs, when the proteins that accomplish splicing bind to pre-mRNAs, and how this influences the type of splicing defect caused by genetic spelling errors. We will also study how communication between different parts of a pre-mRNA that are located far away from one another affects a special type of splicing error called "pseudo-exon" inclusion. Lastly, we will use a specific type of CRISPR technology to introduce thousands of splicing errors in hundreds of human genes. We will determine how each splicing error affects other parts of the pre-mRNAs. Overall, this project will improve our understanding of fundamental splicing mechanisms, which will help determine how splicing goes wrong in rare genetic diseases and could lead to improved prognosis and treatment options for some of these devastating diseases.