Funk is interested in the broad topic of cellular decisions, how cells decide what they will become in a multicellular organism. His cell of choice for these studies is the B-lymphocyte, the cell that produces antibody molecules. B-lymphocytes develop continuously throughout the lifetime of an individual and undergo several distinct steps in their development from hemopoietic stem cells to mature B-lymphocytes. The development of B-lymphocytes is also controlled by other cell types, the stromal cells in bone marrow. B-lymphocytes produce antibody molecules that can be involved in autoimmune diseases and B-lymphocytes that grow abnormally can lead to leukemia. So the body must carefully monitor the growth and development of a B-lymphocyte. One of the most important decisions a B-lymphocyte makes is whether to live or die. Greater than 90% of the B-lymphocytes made will be triggered to die because they have developed a defect of some sort. These cell deaths are important, but no one understands how these cells are told that they must die. Funk's laboratory is currently studying the role of a molecule called chick B6 (chB6) that is present on B-lymphocytes in the chicken and appears to cause a rapid form of cell death when it is bound by an antibody. Interestingly, this molecule can also function and be regulated when placed into mouse cells, suggesting that it has a conserved function. The lab is trying to understand how chB6 functions to initiate cell death and if there are similar molecules in mice and humans.

Li, X.W., J.S. Rees, P. Xue, H. Zhang, S.W. Hamaia, B. Sanderson, P.E. Funk, R.W. Farndale, K.S. Lilley, S. Perrett, and A.P. Jackson. 2014. New Insights into the DT40 B Cell Receptor Cluster Using a Proteomic Proximity Labeling Assay. J. Biol. Chem. 289(21):14434 Funk, P.E., J. Pifer, M. Kharas, G. Crisafi, and A. Johnson. 2003. The Avian chB6 Alloantigen Induces Apoptosis in DT40 B Cells. Cell. Immunol. 226:95. Pifer, J., D. Robison, and P.E. Funk. 2002. The Avian chB6 Alloantigen Triggers Apoptosis in a Mammalian Cell Line. J. of Immunol. 169:1372. Funk, P.E., C.A. Tregaskes, J.R. Young, and C.B. Thompson. 1997. The Avian chB6 (Bu-1) Alloantigen Can Mediate Rapid Cell Death. J. Immunol. 159:1695.