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bioRxiv · 10.1101/2021.06.07.447186

Conservation and diversity in transcriptional responses among host plants forming distinct arbuscular mycorrhizal morphotypes

Tominaga, T.·Miura, C.·Sumigawa, Y.·Hirose, Y.·Yamaguchi, K.·Shigenobu, S.·Mine, A.·Kaminaka, H.
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Abstract

O_LIThe morphotype of arbuscular mycorrhizal (AM) roots is distinct mostly depending on AM host species: Arum, Paris, and Intermediate types. We previously reported that gibberellin (GA) promotes the establishment of Paris-type AM symbiosis in Eustoma grandiflorum despite its negative effects on Arum-type AM symbiosis in model plants. However, the molecular mechanisms underlying the differential effects of GA on different morphotypes, including Intermediate-type AM symbiosis, remain elusive. C_LIO_LIComparative transcriptomics revealed that several symbiosis-related genes were transcriptionally promoted upon AM fungal colonization in Lotus japonicus (Arum-type), Daucus carota (Intermediate-type), and E. grandiflorum (Paris-type). Interestingly, upon GA treatment, the fungal colonization levels and expression of symbiosis-related genes were suppressed in L. japonicus and D. carota but were promoted in E. grandiflorum. C_LIO_LIExogenous GA transcriptionally inhibited the biosynthetic process of a host-derived signal molecule involved in AM symbiosis, strigolactone, in L. japonicus and E. grandiflorum. Additionally, disaccharides mainly metabolized in AM roots would be different between L. japonicus and D. carota/E. grandiflorum. C_LIO_LIThis study uncovered the conserved transcriptional responses during mycorrhization and diverse responses to GA in AM roots with distinct morphotypes among phylogenetically distant host plants. C_LI

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Tominaga, T., Miura, C., Sumigawa, Y., Hirose, Y., Yamaguchi, K., Shigenobu, S., Mine, A., Kaminaka, H.. 2021-06-08. Conservation and diversity in transcriptional responses among host plants forming distinct arbuscular mycorrhizal morphotypes. https://doi.org/10.1101/2021.06.07.447186

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