Rapid Elimination of the Persistent Synergid through a Cell Fusion Mechanism.
In flowering plants, fertilization-dependent degeneration of the persistent synergid cell ensures one-on-one pairings of male and female gametes. Here, we report that the fusion of the persistent synergid cell and the endosperm selectively inactivates the persistent synergid cell in Arabidopsis thaliana. The synergid-endosperm fusion causes rapid dilution of pre-secreted pollen tube attractant in the persistent synergid cell and selective disorganization of the synergid nucleus during the endosperm proliferation, preventing attractions of excess number of pollen tubes (polytubey). The synergid-endosperm fusion is induced by fertilization of the central cell, while the egg cell fertilization predominantly activates ethylene signaling, an inducer of the synergid nuclear disorganization. Therefore, two female gametes (the egg and the central cell) control independent pathways yet coordinately accomplish the elimination of the persistent synergid cell by double fertilization.
Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; Temasek Life Sciences Laboratory and Department of Biological Sciences, National University of Singapore, Singapore 117604, Singapore. Electronic address: maruyama.daisuke@f.mbox.nagoya-u.ac.jp.
Daisuke
D
Maruyama
Center for Plant Molecular Biology (ZMBP), University of Tübingen, 72076 Tübingen, Germany; Center for Desert Agriculture, Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia.
Ronny
R
Völz
JST ERATO Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan.
Hidenori
H
Takeuchi
Waseda Institute for Advanced Study, Waseda University, 1-6-1 Nishiwaseda, Shinjuku-ku, Tokyo 169-8050, Japan.
Toshiyuki
T
Mori
Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo-City, Chiba 271-8510, Japan.
Tomoko
T
Igawa
JST ERATO Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan.
Daisuke
D
Kurihara
Temasek Life Sciences Laboratory and Department of Biological Sciences, National University of Singapore, Singapore 117604, Singapore; Gregor Mendel Institute, Dr-BohrGasse 3, 1030 Vienna, Austria.
Tomokazu
T
Kawashima
Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan.
Minako
M
Ueda
Graduate School of Bioagricultural Sciences and School of Agricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan.
Masaki
M
Ito
Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan; JST, CREST, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
Masaaki
M
Umeda
Department of Life and Food Science, Graduate School of Science, Niigata University, 8050, Ikarashi 2-no-cho, Nishi-ku, Niigata 950-2181, Japan.
Shuh-Ichi
S
Nishikawa
Center for Plant Molecular Biology (ZMBP), University of Tübingen, 72076 Tübingen, Germany; Center for Biomolecular Interactions Bremen, University of Bremen, Leobener Straße NW2 28359, Germany.
Rita
R
Groß-Hardt
Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; Division of Biological Science, 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.
Tetsuya
T
Higashiyama
D017360:Arabidopsis / Q000166:cytology* / Q000196:embryology / Q000378:metabolism*; D002459:Cell Fusion; D056625:Endosperm / Q000378:metabolism; D008938:Mitosis; D010455:Peptides / Q000378:metabolism; D063245:Plant Development; D010940:Plant Proteins / Q000378:metabolism; D053205:Pollen Tube / Q000378:metabolism
D010455:Peptides; D010940:Plant Proteins