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bioRxiv · 10.1101/077669

The appressorium of Magnaporthe oryzae remains mitotically active during post-penetration hyphal growth in rice cells

Kiersun Jones·Cory B Jenkinson·Jie Zhu·Sara Dorhmi·Chang Hyun Khang
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Abstract

To investigate the mitotic dynamics of an appressorium, we used time-lapse confocal imaging of a fluorescence-based mitotic reporter strain of Magnaporthe oryzae. We present evidence that: (i) appressoria remain viable and mitotically active after host penetration, (ii) appressorial mitosis, like invasive hyphal mitosis, is semi-closed, (iii) sister chromatids separate within the appressorium, (iv) a mitotic appressorial nucleus undergoes extreme constriction and elongation as it migrates through the penetration peg in a manner analogous to mitosis during cell-to-cell movement of invasive hyphae. These results provide new insight into the potential roles of the appressorium after host penetration and highlight the unique mitotic dynamics during rice blast infection.

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Kiersun Jones, Cory B Jenkinson, Jie Zhu, Sara Dorhmi, Chang Hyun Khang. 2016-09-26. The appressorium of Magnaporthe oryzae remains mitotically active during post-penetration hyphal growth in rice cells. https://doi.org/10.1101/077669

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