Aster repulsion drives short-ranged ordering in the Drosophila syncytial blastoderm.

Autor: de-Carvalho J; Physics of Intracellular Organization Group, Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal., Tlili S; Mechanobiology Institute, National University of Singapore, 117411 Singapore., Hufnagel L; European Molecular Biology Laboratory, 69117 Heidelberg, Germany., Saunders TE; Mechanobiology Institute, National University of Singapore, 117411 Singapore.; Department of Biological Sciences, National University of Singapore, 117411Singapore.; Institute of Molecular and Cellular Biology, A*Star, Proteos, 138632 Singapore.; Warwick Medical School, University of Warwick, Coventry, CV4 7HL, UK., Telley IA; Physics of Intracellular Organization Group, Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal.
Jazyk: angličtina
Zdroj: Development (Cambridge, England) [Development] 2022 Jan 15; Vol. 149 (2). Date of Electronic Publication: 2022 Jan 26.
DOI: 10.1242/dev.199997
Abstrakt: Biological systems are highly complex, yet notably ordered structures can emerge. During syncytial stage development of the Drosophila melanogaster embryo, nuclei synchronously divide for nine cycles within a single cell, after which most of the nuclei reach the cell cortex. The arrival of nuclei at the cortex occurs with remarkable positional order, which is important for subsequent cellularisation and morphological transformations. Yet, the mechanical principles underlying this lattice-like positional order of nuclei remain untested. Here, using quantification of nuclei position and division orientation together with embryo explants, we show that short-ranged repulsive interactions between microtubule asters ensure the regular distribution and maintenance of nuclear positions in the embryo. Such ordered nuclear positioning still occurs with the loss of actin caps and even the loss of the nuclei themselves; the asters can self-organise with similar distribution to nuclei in the wild-type embryo. The explant assay enabled us to deduce the nature of the mechanical interaction between pairs of nuclei. We used this to predict how the nuclear division axis orientation changes upon nucleus removal from the embryo cortex, which we confirmed in vivo with laser ablation. Overall, we show that short-ranged microtubule-mediated repulsive interactions between asters are important for ordering in the early Drosophila embryo and minimising positional irregularity.
Competing Interests: Competing interests The authors declare no competing or financial interests.
(© 2022. Published by The Company of Biologists Ltd.)
Databáze: MEDLINE