This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a modeling study of sensitivity amplification in signal transduction cascades. While sensitivity amplification has long been regarded as a virtually universal property of signal transduction cascades, a comprehensive parameter analysis remains a challenge even for relatively simple networks.