New human protein map could help pinpoint cancer genes

An international team of scientists has published a paper detailing one of the most comprehensive protein maps to date. Covering 14 000 interactions between protein pairs, the new map is over four times larger than any previous map of its kind. According to Lab Product News, it contains more high-quality interactions than have come from all previous studies put together.

Identifying protein interactions in this way could help researchers understand how cells function on a molecular level, and ultimately help us identify some of the genes involved in cancer. Co-led by Frederick Roth of the University of Toronto and Marc Vidal of Harvard Medical School, the study is the culmination of years of research into human interactome – a complete map of every protein interaction in humans in order to produce this new map.

Identifying protein interactions is almost like creating a manual for the human cell. Speaking to Scientific American, Roth drew an analogy between his work and a mechanic who has a list of car parts but no idea how they interconnect: ‘This takes us from a rough draft of a list of parts, in no particular order, to a list of pairs of parts. Now we can begin to understand how they fit together.’

Scientific American adds: ‘Roth estimates that the new map captures between 5 and 10 percent of all the protein interactions in human cells. That may not sound like a lot, but the last big advance for the human interactome was almost a decade ago, when Roth released his first map of only about 3,000 protein interactions.’

The scientists used lab experiments to identify interactions and then used computer modelling to zero in on proteins that connect to one or more other cancer proteins.

Speaking to Lab Product News, Roth noted that this is the first time that a study has shown that cancer proteins are more likely to interconnect with one another than they are to connect to randomly chosen non-cancer proteins. He added, ‘Once you see that proteins associated to the same disease are more likely to connect to each other, now you can use this network of interactions as a prediction tool to find new cancer proteins, and the genes they encode.’

Scientific American points to the immediate applications for cancer research: ‘Studies have linked the gene MAPK1IP1L to tumor formation in mice, but it has not been studied extensively and the protein that it produces is not currently recognized as a cancer protein in humans. Roth’s study found that MAPK1IP1L interacts with at least three known cancer proteins. That does not necessarily mean MAPK1IP1L is a cancer gene, but it does suggest an avenue for future research.’

For more information, please visit:
http://www.cell.com/cell/abstract/S0092-8674%2814%2901422-6