Multiplecis-acting signals, some weak by necessity, collectively direct robust transport ofoskarmRNA to the oocyte

Young Hee Ryu, Andrew Kenny, Youme Gim, Mark Snee, Paul M. Macdonald
2017 Journal of Cell Science  
Localization of mRNAs can involve multiple steps, each with its own cisacting localization signals and transport factors. How is the transition between different steps orchestrated? We show that the initial step in localization of Drosophila oskar mRNA − transport from nurse cells to the oocyte − relies on multiple cis-acting signals. Some of these are binding sites for the translational control factor Bruno, suggesting that Bruno plays an additional role in mRNA transport. Although transport
more » ... oskar mRNA is essential and robust, the localization activity of individual transport signals is weak. Notably, increasing the strength of individual transport signals, or adding a strong transport signal, disrupts the later stages of oskar mRNA localization. We propose that the oskar transport signals are weak by necessity; their weakness facilitates transfer of the oskar mRNA from the oocyte transport machinery to the machinery for posterior localization.
doi:10.1242/jcs.202069 pmid:28760927 fatcat:klfevn5mh5getprf7vgvzcz7va