Merabet Samir, Saadaoui Mehdi, Sambrani Nagraj, Hudry Bruno, Pradel Jacques, Affolter Markus, Graba Yacine
Institut de Biologie du Développement de Marseille Luminy, Centre National de la Recherche Scientifique, Université de la Méditerranée, Parc Scientifique de Luminy, 13288 Marseille Cedex 09, France.
Proc Natl Acad Sci U S A. 2007 Oct 23;104(43):16946-51. doi: 10.1073/pnas.0705832104. Epub 2007 Oct 17.
Hox transcription factors are essential for shaping body morphology in development and evolution. The control of Hox protein activity in part arises from interaction with the PBC class of partners, pre-B cell transcription factor (Pbx) proteins in vertebrates and Extradenticle (Exd) in Drosophila. Characterized interactions occur through a single mode, involving a short hexapeptide motif in the Hox protein. This apparent uniqueness in Hox-PBC interaction provides little mechanistic insight in how the same cofactors endow Hox proteins with specific and diverse activities. Here, we identify in the Drosophila Ultrabithorax (Ubx) protein a short motif responsible for an alternative mode of Exd recruitment. Together with previous reports, this finding highlights that the Hox protein Ubx has multiple ways to interact with the Exd cofactor and suggests that flexibility in Hox-PBC contacts contributes to specify and diversify Hox protein function.
Hox转录因子对于在发育和进化过程中塑造身体形态至关重要。Hox蛋白活性的控制部分源于与PBC类伙伴的相互作用,在脊椎动物中是前B细胞转录因子(Pbx)蛋白,在果蝇中是额外齿状蛋白(Exd)。已表征的相互作用通过单一模式发生,涉及Hox蛋白中的一个短六肽基序。Hox-PBC相互作用中的这种明显独特性几乎没有提供关于相同辅因子如何赋予Hox蛋白特定和多样活性的机制见解。在这里,我们在果蝇超双胸(Ubx)蛋白中鉴定出一个负责Exd募集替代模式的短基序。与先前的报告一起,这一发现突出表明Hox蛋白Ubx有多种与Exd辅因子相互作用的方式,并表明Hox-PBC接触的灵活性有助于确定和多样化Hox蛋白功能。