Meeting Abstract
Regeneration may be viewed as the activation of a non-embryonic developmental program in response to injury. This program necessarily involves a change in the expression profile of proteins in order to rebuild the lost organ, including those regulating the process. Shotgun liquid chromatography/mass spectroscopy is a rapidly improving proteomic method for globally assessing protein expression profiles. We have begun using this technology to assay proteins up or downregulated in regenerating tissue in the ascidian Ciona intestinalis. This animal is capable of regenerating its oral siphon when removed. By comparing protein expression profiles from intact siphon tissue vs. regenerating siphon blastema we are identifying molecules that may be important for regulating the regeneration process. In preliminary experiments over 300 total proteins were identified, with 133 proteins upregulated and 107 downregulated in regenerating tissue. Of particular interest were a number of signaling molecules, RNA binding proteins, and transcription factors. Ongoing work includes selecting for nuclear proteins, to enrich for transcription factors, and assaying additional stages and replicates.