Spatiotemporal deep imaging of syncytium induced by the soybean cyst nematode Heterodera glycines.
Parasite infections cause dramatic anatomical and ultrastructural changes in host plants. Cyst nematodes are parasites that invade host roots and induce a specific feeding structure called a syncytium. A syncytium is a large multinucleate cell formed by cell wall dissolution-mediated cell fusion. The soybean cyst nematode (SCN), Heterodera glycines, is a major soybean pathogen. To investigate SCN infection and the syncytium structure, we established an in planta deep imaging system using a clearing solution ClearSee and two-photon excitation microscopy (2PEM). Using this system, we found that several cells were incorporated into the syncytium; the nuclei increased in size and the cell wall openings began to be visible at 2 days after inoculation (DAI). Moreover, at 14 DAI, in the syncytium developed in the cortex, there were thickened concave cell wall pillars that resembled "Parthenon pillars." In contrast, there were many thick board-like cell walls and rarely Parthenon pillars in the syncytium developed in the stele. We revealed that the syncytia were classified into two types based on the pattern of the cell wall structures, which appeared to be determined by the position of the syncytium inside roots. Our results provide new insights into the developmental process of syncytium induced by cyst nematode and a better understanding of the three-dimensional structure of the syncytium in host roots.
Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan. ootsu.mina@d.mbox.nagoya-u.ac.jp.
Mina
http://orcid.org/0000-0001-7479-8455
M
Ohtsu
Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.
Yoshikatsu
Y
Sato
Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.|JST ERATO Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.
Daisuke
D
Kurihara
Graduate School of Life and Environmental Sciences, University of Tsukuba, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan.
Takuya
T
Suzaki
Division of Symbiotic Systems, National Institute for Basic Biology (NIBB), Okazaki, Aichi, 444-8585, Japan.
Masayoshi
M
Kawaguchi
Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka-cho, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan.
Daisuke
D
Maruyama
Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.|Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.|JST ERATO Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.
Tetsuya
T
Higashiyama
D000818:Animals; D002473:Cell Wall / Q000469:parasitology; D015726:Giant Cells / Q000166:cytology / Q000469:parasitology; D008856:Microscopy, Fluorescence; D018517:Plant Roots / Q000166:cytology / Q000469:parasitology*; D013025:Glycine max / Q000166:cytology / Q000469:parasitology*; D062211:Spatio-Temporal Analysis; D014431:Tylenchoidea / Q000502:physiology*
Deep imaging; Heterodera; Plant-parasitic nematode; Syncytium development; Two-photon excitation microscopy (2PEM)