Yu, D., Baird, M.A., Allen, J.R., Howe, E.S., Klassen, M.P., Reade, A., Makhijani, K., Song, Y., Liu, S., Murthy, Z., Zhang, S.Q., Weiner, O.D., Kornberg, T.B., Jan, Y.N., Davidson, M.W., Shu, X. (2015) A naturally monomeric infrared fluorescent protein for protein labeling in vivo. Nature Methods. 12(8):763-5.
Infrared fluorescent proteins (IFPs) provide an additional color to GFP and its homologs in protein labeling. Drawing on structural analysis of the dimer interface, we identified a bacteriophytochrome in the sequence database that is monomeric in truncated form and engineered it into a naturally monomeric IFP (mIFP). We demonstrate that mIFP correctly labels proteins in live cells, Drosophila and zebrafish. It should be useful in molecular, cell and developmental biology.