A new study from MIT and collaborating institutions implicates a family of RNA-binding proteins in the regulation of cancer, particularly in a subtype of breast cancer. These proteins, known as Musashi proteins, can force cells into a state associated with increased proliferation. Biologists have previously found that this kind of transformation, which often occurs in cancer cells as well as during embryonic development, is controlled by transcription factors — proteins that turn genes on and off. However, the new MIT research reveals that RNA-binding proteins also play an important role. Human cells have about 500 different RNA-binding proteins, which influence gene expression by regulating messenger RNA, the molecule that carries DNA’s instructions to the rest of the cell. “Recent discoveries show that there’s a lot of RNA-processing that happens in human cells and mammalian cells in general,” says Dr. Yarden Katz, a recent MIT Ph.D. recipient and one of the lead authors of the new paper. “RNA is processed at several points within the cell, and this gives opportunities for RNA-binding proteins to regulate RNA at each point. We’re very interested in trying to understand this unexplored class of RNA-binding proteins and how they regulate cell-state transitions.” Dr. Feifei Li of China Agricultural University is also a lead author of the paper, which was published online on November 7, 2014 in an open-access article in eLife. Senior authors of the paper are MIT biology professors Dr. Christopher Burge and Dr. Rudolf Jaenisch, and Dr. Zhengquan Yu of China Agricultural University. Until this study, scientists knew very little about the functions of Musashi proteins. These RNA-binding proteins have traditionally been used to identify neural stem cells, in which they are very abundant.Login Or Register To Read Full Story