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bioRxiv · 10.1101/224626

Re-arrangements in the cytoplasmic distribution of small RNAs following the maternal-to-zygotic transition in Drosophila embryos

Cosacak, M. I.·Yigit, H.·Akgul, B.
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Abstract

Small RNAs are known to regulate gene expression during early development. However, the dynamics of interaction between small RNAs and polysomes during this process is largely unknown. 0-1h and 7-8h Drosophila embryos were fractionated on sucrose density gradients into four fractions based on A254 reading (1) translationally inactive messengerribonucleoprotein (mRNP); (2) 60S; (3) monosome; and (4) polysome. Comparative analysis of deep-sequencing reads from fractionated and un-fractionated 0-1h and 8-h embryos revealed development-specific co-sedimentation pattern of small RNAs with the cellular translation machinery. Although most miRNAs did not have a specific preference for any state of the translational machinery, we detected fraction-specific enrichment of some miRNAs such as miR-1-3p, -184-39, 5-5p and 263-5p. More interestingly, we observed dysregulation of a subset of miRNAs in fractionated embryos despite no measurable difference in their amount in unfractionated embryos. Transposon-derived endosiRNAs are over-expressed in 7-8h embryos and are associated mainly with the mRNP fraction. However, transposon-derived piRNAs, which are more abundant in 0-1h embryos, co-sediment primarily with the polysome fractions. These results suggest that there appears to be a complex interplay among the small RNAs with respect to their polysome-cosedimention pattern during early development in Drosophila.

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Cosacak, M. I., Yigit, H., Akgul, B.. 2017-11-24. Re-arrangements in the cytoplasmic distribution of small RNAs following the maternal-to-zygotic transition in Drosophila embryos. https://doi.org/10.1101/224626

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