title: Functional analysis of the microtubule-interacting transcriptome.
abstract: RNA localization is an important mechanism for achieving precise control of posttranscriptional gene expression. Previously, we demonstrated that a subset of cellular mRNAs copurify with mitotic microtubules in egg extracts of Xenopus laevis. Due to limited genomic sequence information available for X. laevis, we used RNA-seq to comprehensively identify the microtubule-interacting transcriptome of the related frog Xenopus tropicalis. We identified ~450 mRNAs that showed significant enrichment on microtubules (MT-RNAs). In addition, we demonstrated that the MT-RNAs incenp, xrhamm, and tpx2 associate with spindle microtubules in vivo. MT-RNAs are enriched with transcripts associated with cell division, spindle formation, and chromosome function, demonstrating an overrepresentation of genes involved in mitotic regulation. To test whether uncharacterized MT-RNAs have a functional role in mitosis, we performed RNA interference and discovered that several MT-RNAs are required for normal spindle pole organization and γ-tubulin distribution. Together, these data demonstrate that microtubule association is one mechanism for compartmentalizing functionally related mRNAs within the nucleocytoplasmic space of mitotic cells and suggest that MT-RNAs are likely to contribute to spindle-localized mitotic translation.
authors.affiliation: Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Judith A
authors.initials: JA
authors.lastname: Sharp
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Plant
authors.forename: Toshiro K
authors.initials: TK
authors.lastname: Ohsumi
authors.forename: Mark
authors.initials: M
authors.lastname: Borowsky
authors.forename: Michael D
authors.initials: MD
authors.lastname: Blower
mesh_terms: D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics; D002455:Cell Division; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000235:genetics / Q000378:metabolism*; D008938:Mitosis; D009687:Nuclear Proteins / Q000235:genetics; D010750:Phosphoproteins / Q000235:genetics; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism*; D034741:RNA, Small Interfering; D016415:Sequence Alignment; D017423:Sequence Analysis, RNA; D008941:Spindle Apparatus / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome; D014404:Tubulin; D014981:Xenopus; D029867:Xenopus Proteins / Q000235:genetics
chemical_list: D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; C000623051:Hmmr protein, Xenopus; C506222:INCENP protein, Xenopus; D008869:Microtubule-Associated Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C486551:TPX2 protein, Xenopus; D014404:Tubulin; D029867:Xenopus Proteins