| Autor: |
Baumann S; Heinrich Heine University Düsseldorf, Institute for Microbiology, 40204 Düsseldorf, Germany., Pohlmann T, Jungbluth M, Brachmann A, Feldbrügge M |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of cell science [J Cell Sci] 2012 Jun 01; Vol. 125 (Pt 11), pp. 2740-52. Date of Electronic Publication: 2012 Feb 22. |
| DOI: |
10.1242/jcs.101212 |
| Abstrakt: |
Long-distance transport of mRNAs is important in determining polarity in eukaryotes. Molecular motors shuttle large ribonucleoprotein complexes (mRNPs) containing RNA-binding proteins and associated factors along microtubules. However, precise mechanisms including the interplay of molecular motors and a potential connection to membrane trafficking remain elusive. Here, we solve the motor composition of transported mRNPs containing the RNA-binding protein Rrm4 of the pathogen Ustilago maydis. The underlying transport process determines the axis of polarity in infectious filaments. Plus-end-directed Kin3, a kinesin-3 type motor, mediates anterograde transport of mRNPs and is also present in transport units moving retrogradely. Split dynein Dyn1-Dyn2 functions in retrograde movement of mRNPs. Plus-end-directed conventional kinesin Kin1 is indirectly involved by transporting minus-end-directed dynein back to plus ends. Importantly, we additionally demonstrate that Rrm4-containing mRNPs colocalise with the t-SNARE Yup1 on shuttling endosomes and that functional endosomes are essential for mRNP movement. Either loss of Kin3 or removal of its lipid-binding pleckstrin-homology domain abolishes Rrm4-dependent movement without preventing colocalisation of Rrm4 and Yup1-positive endosomes. In summary, we uncovered the combination of motors required for mRNP shuttling along microtubules. Furthermore, intimately linked co-transport of endosomes and mRNPs suggests vesicle hitchhiking as mode of mRNP transport. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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