Norris, M. L. | Search bioRxiv

bioRxiv2026

GLOBAL ANALYSIS OF PROTRUSION-TRANCSRIPTOMES IDENTIFIES DISTINCT CATEGORIES OF LOCALIZED RNAS IN NON-NEURONAL CELLS

RNA localization to protrusions in non-neuronal cells is an emerging molecular process, distinct from the canonical mechanism characterized in neurons. Here, we describe a fractionation workflow optimized for non-neuronal cells that increases sensitivity and reproducibility of transcriptome-wide quantification of protrusion-localized RNAs. Using the optimized method, we identify six categories of protrusion-localized RNAs in non-neuronal cells from mice, including long non-coding RNAs and pseudogenes, and observe spatially distinct subsets of mitochondrially-localized RNAs. Taken together, our results reveal previously unappreciated spatial regulation of diverse transcripts and point toward broadly acting unifying principles that extend across cell types and species.

molecular biology↗

bioRxiv2022

Localization of Kif1c mRNA to cell protrusions dictates binding partner specificity of the encoded protein

Subcellular localization of messenger RNA (mRNA) is a widespread phenomenon that can impact the regulation and function of the encoded protein. In non-neuronal cells, a subset of mRNAs localize to cell protrusions and proper mRNA localization is required for cell migration. However, the mechanisms by which mRNA localization regulates protein function in this setting remain unclear. Here, we examined the functional consequences of localization of the mRNA encoding KIF1C. KIF1C is a kinesin motor protein required for cell migration and mRNA trafficking, including trafficking of its own mRNA. We show that Kif1c mRNA localization does not regulate KIF1C protein abundance, distribution, or ability to traffic other mRNAs. Conversely, robust Kif1c mRNA localization is required for directed cell migration. We used mass spectrometry to identify binding partners of endogenous KIF1C, which revealed dramatic dysregulation of the number and identity of KIF1C interactors in response to Kif1c mRNA mis-localization. These results therefore uncovered a mechanistic connection between mRNA localization to cell protrusions and the specificity of protein-protein interactions. We anticipate that this mechanism is not limited to Kif1c and is likely to be a general principle used by protrusion-enriched mRNAs in non-neuronal cells.

molecular biology↗