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bioRxiv · 10.1101/2021.04.17.440084

Phytophthora capsici sterol reductase PcDHCR7 has a role in mycelium development and pathogenicity

Wang, W.·Zhang, F.·Zhang, S.·Xue, Z.·Xie, L.·Govers, F.·Liu, X.
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Abstract

The de novo biosynthesis of sterols is critical for eukaryotes, however, some organisms lack this pathway including most oomycetes. Phytophthora spp. are sterol auxotroph but remarkably, have retained a few genes encoding enzymes in the sterol biosynthesis pathway. Here we investigated the function of PcDHCR7, a gene in Phytophthora capsici predicted to encode the {bigtriangleup}7-sterol reductase. When expressed in Saccharomyces cerevisiae, PcDHCR7 showed a {bigtriangleup}7-sterol reductase activity. Knocking out PcDHCR7 in P. capsici resulted in loss of the capacity to transform ergosterol into brassicasterol, which means PcDHCR7 has a {bigtriangleup}7-sterol reductase activity in P. capsici itself. This enables P. capsici to transform sterols recruited from the environment for better use. Biological characteristics were compared between wild-type isolate and PcDHCR7 knock-out transformants. The results indicated that PcDHCR7 plays a key role in mycelium development and pathogenicity of zoospores in P. capsici.

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Wang, W., Zhang, F., Zhang, S., Xue, Z., Xie, L., Govers, F., Liu, X.. 2021-04-17. Phytophthora capsici sterol reductase PcDHCR7 has a role in mycelium development and pathogenicity. https://doi.org/10.1101/2021.04.17.440084

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