Systematic analysis of the MAPK signaling network reveals MAP3K-driven control of cell fate.

The classic network of mitogen-activated protein kinases (MAPKs) is highly interconnected and controls a diverse array of biological processes. In multicellular eukaryotes, the MAPKs ERK, JNK, and p38 control opposing cell behaviors but are often activated simultaneously, raising questions about how input-output specificity is achieved. Here, we use multiplexed MAPK activity biosensors to investigate how cell fate control emerges from the connectivity and dynamics of the MAPK network. Through chemical and genetic perturbation, we systematically explore the outputs and functions of all the MAP3 kinases encoded in the human genome and show that MAP3Ks control cell fate by triggering unique combinations of MAPK activity. We show that these MAPK activity combinations explain the paradoxical dual role of JNK signaling as pro-apoptotic or pro-proliferative kinase. Overall, our integrative analysis indicates that the MAPK network operates as a unit to control cell fate and shifts the focus from MAPKs to MAP3Ks to better understand signaling-mediated control of cell fate.

Mannheimia haemolytica chimeric protein vaccine composed of the major surface-exposed epitope of outer membrane lipoprotein PlpE and the neutralizing epitope of leukotoxin.

Mannheimia haemolytica is commonly identified in cattle with shipping fever pneumonia. Vaccines currently available do not provide complete protection against the disease. In an effort to develop a vaccine that delivers the immunogenic regions of leukotoxin (LKT) A and the outer membrane protein (OMP) PlpE, a total of four chimeric proteins were constructed. Mice were subcutaneously immunized with 25, 50 and 75 microg quantities of each chimeric protein. The specificity of the immune response was confirmed by Western blot analysis and enzyme-linked immunosorbent assays (ELISA). Moreover, the hyperimmune sera were bactericidal to M. haemolytica in the presence of complement and neutralized LKT. While all of the chimeric proteins induced some level of immune response two, SAC87 and SAC89, were most promising. These results demonstrate that a functional immune response against M. haemolytica can be induced by vaccination with recombinant chimeric proteins created from specific immunogenic regions of the LKT and PlpE proteins.