Our work on the planarian ortholog of the TALE class homeobox protein PBX/extradenticle has been published in the journal “Development”. This work was begun by Daniel Felix during his PhD thesis where he observed a very strong phenotype for this gene whilw focused on charactering another TALE class Homeobox called PREP. Robert followed this up with a very comprehensive set of experiments to characterise exactly what pbx does in planarians. Robert in particular deserves a lot of recogniton for coming in as a planarian novice and being so productive and thoughtful about the project in such a short period of time. Belen then helped tie up some loose ends with some “essential experiments before the paper could be published” that the reviewers kindly thought up (hence the burgeoning suppplementary information for this paper). While these were interesting they didn’t add much to the main findings and may actually have made it harder for other groups (for example working on the order events that lead to midline specification) to publish more focuses studies in this area.
Overall we are really excited as pbx seems to have a central role in allowing stem cells and the their progeny to interpret their position. We think that it may be a key player in providing coordinate positional information to differentiating cells during regeneration as it has the potential to interact with large number fo cofactors when controling gene expression and act downstream of many signalling cascades. We hope to pursue our findings by looking at the detail of what and how pbx and prep regulate to confer positional information.
Also in the same issue of Development is a another paper on the same gene from Peter Reddien’s group at MIT/Whitehead. We think the papers are very complementary and we are grateful too Peter for taking the decision to wait for our paper to be reconsidered after the paper from his group was accepted. We took little longer to add experiments to investigate eye regeneration, midline patterning, pharynx regeneration and in situs on sections requested by the reviewers.
You can check out the paper here