Mapping the targets of RNase MRP (360G-Wellcome-213011_Z_18_Z)

Cartilage hair hypoplasia, or CHH, is an uncommon disease. Patients with this disease have short limbs and thin hair. They also have problems with their immune system, making them vulnerable to infections. These patients have a mutation in their DNA, in a gene called RMRP. In healthy people, we think RMRP helps build ribosomes. Ribosomes are the cell’s factories which turn the instructions in DNA into the proteins which make up the body. But this happens in all cells, and so it is hard to understand why people with CHH only have problems with their bones and immune system, while most other organs work well. Understanding this is a first step to thinking about new treatments. We will use recently developed techniques to map all the molecules in the cell which interact with RMRP. We will initially apply these in yeast cells, which are similar to human cells, and in human cells grown in the laboratory. We will then determine what happens when we introduce the DNA changes seen in patients into these cells, and into a laboratory mouse strain. This will give us a better understanding of how RMRP normally works, and what goes wrong in the patients.