Rxiv cytoskeletonhttps://www.biorxiv.org/content/10.64898/2026.06.09.731215v1?rss=1
#Kinesin
Robust mammalian RNA localization elements are complex and multipartite
The subcellular localization patterns of RNAs are controlled by regulatory elements contained within them. However, for most localized RNAs, the identities of these elements remain unknown. We had previously identified several localization elements that are necessary and sufficient for robust, kinesin-dependent RNA targeting to microtubule plus ends in a variety of cell types. Yet the characteristics of these elements that are critical for function remained unclear. To address this, we systematically created tens of thousands of mutant localization elements and quantified their ability to regulate subcellular RNA localization in neuronal cells. We found that the minimally active size of these localization elements is large, approximately 200 nucleotides. These elements contain multiple important subsequences, with some being completely intolerant of any changes and others being tolerant to a shuffling of nucleotide order but not to changes in nucleotide composition. Using single molecule microscopy, we verified these findings in primary rat neurons. Together, these results demonstrate that highly active mammalian RNA localization elements are large, complex, and multipartite and lay a foundation for further mechanistic studies of their function. ### Competing Interest Statement The authors have declared no competing interest. National Institute of General Medical Sciences, https://ror.org/04q48ey07, R35GM133385, F31GM151819, T32GM136444, R01GM155542, R35GM156773 National Institute of Neurological Disorders and Stroke, https://ror.org/01s5ya894, R01NS122911 Deutsche Forschungsgemeinschaft, Ki 502/9-1, 506658941 Friedrich Baur Stiftung, https://ror.org/032a9fh96
Rxiv mechanobio