Genes are strings of DNA molecules. They are found on chromosomes within cell nuclei. DNA is like a storage bin for vital information -- like the hard drive of a computer. To be useful, a computer hard drives needs to run a program that performs work. It's the same with DNA. To be useful, it runs programs (RNAs) that make desired products. The products are proteins. Proteins are the substances that carry out all life functions, which is why advanced cancer research focuses on them.
To do their jobs, proteins need to be activated. They become activated by binding to other protein partners. The Mayo Clinic team investigated a specific kind of protein the BRCA1 gene codes for, known as a BRCT-domain protein. The BRCT-domain influences how the protein binds and with what protein partners it binds -- which in turn, affects the role the protein plays in the cycle of cell growth. BRCT domains are found in many proteins involved in cell-cycle regulation, and have for some years been thought to be key players in cell-cycle regulation. But just how they did so was not known.
The Mayo Clinic Research Solves The Mystery
The Mayo team showed that phosphorylation of a binding partner is necessary to activate the BRCT-domain protein. Once activated, the BRCT-domain protein then helps regulate vital tasks in the cell cycle. These tasks include repairing DNA or signaling DNA damage. When these tasks are accomplished, the BRCA1 gene can function correctly to suppress tumors. Without phosphorylation of BRCA1 binding partners, BRCA1 cannot function to suppress tumors. This leaves cells vulnerable to the cumulative mutations that can eventually produce breast cancer.