1. Measuring Sphingosine-1-Phosphate/Protein Interactions with the Kinetic Exclusion Assay Jonathan K. Fleming and Jonathan M. Wojciak 2. An Improved Isoform-Selective Assay for Sphingosine Kinase 1 Activity Melissa R. Pitman, Lorena T. Davies, and Stuart M. Pitson 3. Methods for Analyzing Sphingosine-1-Phosphate Signaling in Human and Mouse Primary Mast Cells