Factors affecting sex-ratio variation and sex-determining mechanisms in the apple snail Pomacea canaliculata

2009 Fiscal Year Final Research Report

• Project/Area Number: 19570019
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Ecology/Environment
• Research Institution: Nara Women's University
• Principal Investigator: YUSA Yoichi Nara Women's University, 理学部, 准教授 (60355641)
• Co-Investigator(Kenkyū-buntansha): IWAGUCHI Shin-ichi 奈良女子大学, 理学部, 准教授 (40263420)
• Project Period (FY): 2007 – 2009
• Keywords: 生態学 / 進化 / 遺伝学 / 性決定 / 性比 / 軟体動物

Research Abstract

The freshwater snail Pomacea canaliculata shows a large variation in offspring sex ratio. We investigated whether this variation is caused by a small number of sex-determining genes, with two series of experiments. First, we reared F2 offspring from several crosses involving full-sib sisters with the same male, and determined sex ratios of F2. The sex ratios of F2 converged into a few values, indicating that the sex-determining genotypes of the F1 full-sib sisters were also a few. This suggests that the sex in this snail is determined by a few genes rather than polygenes. Secondly, we developed genetic markers to study linkage with the putative sex-determining genes. We found >40 microsatellite loci, and developed four useful markers. These markers were repeatable in PCR, polymorphic and followed Mendelian segregation. We conducted fragment analyses in two populations (Kumamoto and Nara) with these markers. One of them showed significantly different frequencies between males and females in both populations ; it may be in the same linkage group as a sex-determining locus.

Research Products

• [Journal Article] Learned predator recognition in a freshwater snail (2010)
  • Author(s): Aizaki, K., Yusa, Y.
  • Journal Title: Pomacea canaliculata. Malacologia 52 Pages: 21-29
  • Peer Reviewed
• [Journal Article] 西南暖地において水田から用水路に流出するスクミリンゴガイの個体数 (2009)
  • Author(s): 和田節, 松倉啓一郎, 吉田和弘, 山西陽子, 遊佐陽一
  • Journal Title: 九州病害虫研究会報 55 Pages: 93-98
  • Peer Reviewed
• [Journal Article] Life cycle of the apple snail Pomacea canaliculata (Caenogastropoda: Ampullariidae) inhabiting Japanese paddy fields (2009)
  • Author(s): Yoshida, K., Hoshikawa, K, Wada, T., Yusa, Y.
  • Journal Title: Applied Entomology and Zoology 44 Pages: 465-474
  • Peer Reviewed
• [Journal Article] 奈良八重桜から分離した花酵母でつくった爽やかな旨味の清酒 (2009)
  • Author(s): 岩口伸一、鈴木孝仁、松澤一幸、清水浩美、大橋正孝、都築正男、藤野千代
  • Journal Title: 生物工学 87 Pages: 356-357
  • Peer Reviewed
• [Journal Article] Field observations of the alarm response to crushed conspecifics in the freshwater snail Pomacea canaliculata: effects of habitat, vegetation, and body size (2009)
  • Author(s): Aizaki, K., Yusa, Y.
  • Journal Title: Journal of Ethology 27 Pages: 175-180
  • Peer Reviewed
• [Journal Article] The loss of parts of chromosome 7 followed by the insertion of URA cassette into RB2 on MRS in Candida albicans strain CAI-4. (2008)
  • Author(s): Iwaguchi, S., Suzuki, M., Sakai, N., Yokoyama, K., Suzuki, T.
  • Journal Title: Medical Mycology 46 Pages: 655-663
  • Peer Reviewed
• [Journal Article] Causes of variation in sex ratio and modes of sex determination in the Mollusca-an overview (2007)
  • Author(s): Yusa, Y.
  • Journal Title: American Malacological Bulletin 23 Pages: 89-98
  • Peer Reviewed
• [Journal Article] A water-borne sex pheromone and trail following in the apple snail, Pomacea canaliculata (2007)
  • Author(s): Takeichi, M., Hirai, Y., Yusa, Y.
  • Journal Title: Journal of Molluscan Studies 73 Pages: 275-278
  • Peer Reviewed
• [Presentation] 捕食者種によるスクミリンゴガイの逃避行動の違い (2010)
  • Author(s): 上島慧里子, 遊佐陽一
  • Organizer: 第57回日本生態学会大会
  • Place of Presentation: 東京
  • Year and Date: 2010-03-17
• [Presentation] 生物的抵抗性を利用したスクミリンゴガイ広域的管理の可能性 (2010)
  • Author(s): 遊佐陽一, 原明子, 吉田和弘
  • Organizer: 農研機構シンポジウム「水田農業の新たな展開と技術」
  • Place of Presentation: 東京
  • Year and Date: 2010-03-15
• [Presentation] Sperm competition among dwarf males of Scalpellum stearnsii (Cirripedia: Lepadomorpha) as revealed by microsatellite markers (2009)
  • Author(s): Ozaki, Y., Iwaguchi, S., Yusa, Y.
  • Organizer: The Crustacean Society Summer Meeting
  • Place of Presentation: 東京
  • Year and Date: 2009-09-22
• [Presentation] Ecological roles of microbial volatile organic compounds (MVOCs) in Aspergillus fumigatus (2009)
  • Author(s): Iwaguchi, S., Takaeuchi, T., Kiuchi, M., Okubo, M., Hosokawa, Y., Matsutani, T., Hashimoto, Y., Yokoyama, K., Suzuki, T.
  • Organizer: The 17th Congress of International Society for Human and Animal Mycology
  • Place of Presentation: 東京
  • Year and Date: 2009-05-29
• [Presentation] マイクロサテライトマーカーを用いたミョウガガイの矮雄間競争の解明 (2009)
  • Author(s): 尾崎有紀, 岩口伸一, 遊佐陽一
  • Organizer: 第56回日本生態学会大会
  • Place of Presentation: 盛岡
  • Year and Date: 2009-03-19
• [Presentation] 水田生態系におけるスクミリンゴガイを介した間接効果 (2008)
  • Author(s): 吉江春子, 遊佐陽一
  • Organizer: 第55回日本生態学会大会
  • Place of Presentation: 福岡
  • Year and Date: 2008-03-16
• [Presentation] Sexual selection and sex allocation in Aplysia: hermaphrodites with nonreciprocal mating (2007)
  • Author(s): Yusa, Y.
  • Organizer: World Congress on Malacology
  • Place of Presentation: Antwerp, Belgium
  • Year and Date: 20070715-20070720
• [Presentation] 植物から得られた真菌のInternal transcribed spacer regions (ITS1, ITS2)による検出と同定 (2007)
  • Author(s): 岩口伸一, 鈴木孝仁
  • Organizer: 第71回日本植物学会年会
  • Place of Presentation: 千葉県野田市
  • Year and Date: 2007-09-07