The Development Inhibitor and its Playmates

M. xanthus is a gram negative member of the Myxococcus family that forms biofilms. M. xanthus is a model organism for studying cell signaling as it is a social bacterium that regulates its behavior in response to external signals. When it lacks the nutrients needed to sustain itself, it sporulates and forms fruiting bodies. Two transcription factors, MrpC, and FruA, modulate the expression of 1000s of genes during starvation-induced cell-differentiation. One of the loci regulated by these proteins is an operon called the dev operon. DevI, a 40-amino acid peptide product of the dev operon, acts as a sporulation timer. The role of small proteins in gene regulation is increasingly being recognized. DevI prevents M. xanthus from unnecessary sporulation by giving the bacteria more time to respond to the starvation signal before committing to the time and energy consuming process. DevI positively regulates transcription from the dev operon and the genes that code for MrpC and FruA, but the mechanism is unknown. We hypothesized that DevI could act as a modulator of transcription by interacting with MrpC and FruA and helping them bind to promoter recognitions sites. A bacterial 2 hybrid analysis preformed between FruA, MrpC, and DevI will be the first step to shining light on how the DevI protein regulates sporulation timing, and promises novel insights into the means by which small proteins regulate cellular processes. Understanding how DevI works will also allow for future potentials such as preventing biofilm formation in industrial pipelines