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bioRxiv · 10.1101/2021.05.07.443143

Symmetry breaking in the female germline cyst

Nashchekin, D.·Busby, L.·Jacobs, M.·Squires, I.·St Johnston, D.
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Abstract

In mammals and flies, only a limited number of cells in a multicellular female germline cyst become oocytes, but how the oocyte is selected is unknown. Here we show that the microtubule minus end-stabilizing protein, Patronin/CAMSAP marks the future Drosophila oocyte and is required for oocyte specification. The spectraplakin, Shot, recruits Patronin to the fusome, a branched structure extending into all cyst cells. Patronin stabilizes more microtubules in the cell with most fusome and this weak asymmetry is amplified by Dynein-dependent transport of Patronin-stabilized microtubules. This forms a polarized microtubule network, along which Dynein transports oocyte determinants into the presumptive oocyte. Thus, Patronin amplifies a weak fusome anisotropy to break cyst symmetry. These findings reveal a molecular mechanism of oocyte selection in the germline cyst.

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Nashchekin, D., Busby, L., Jacobs, M., Squires, I., St Johnston, D.. 2021-05-07. Symmetry breaking in the female germline cyst. https://doi.org/10.1101/2021.05.07.443143

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