Study on regulatory mechanisms of hypotonic stress-tolerance in the red seaweed Bangia fuscopurpurea

2015 Fiscal Year Final Research Report

• Project/Area Number: 25660160
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Aquatic life science
• Research Institution: Hokkaido University
• Principal Investigator: Mikami Koji 北海道大学, 水産科学研究科(研究院), 准教授 (40222319)
• Co-Investigator(Renkei-kenkyūsha): ITABASHI Yutaka 北海道大学, 大学院水産科学研究院, 特任教授 (60142709) ; KATO Atsusi 北海道大学, 大学院理学研究院, 教授 (90177428) ; YOKOYAMA Takehiko 北里大学, 水産学部, 講師 (60296431)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 環境ストレス耐性 / 低塩類濃度ストレス / 細胞収縮 / 葉緑体 / 遺伝子発現 / トランスクリプトーム解析 / ウシケノリ

Outline of Final Research Achievements

The marine red seaweed Bangia fuscopurpurea can adapt and live in fresh water, for which cell shrinkage occurs against physiological consensus of hypotonic stress-dependent cell swelling. The study was performed to elucidate the mechanism of such a special regulation in fresh water tolerance in B. fuscopurpurea. As results, intracellular contents of free amino acids was reduced by fresh water treatment, whereas fatty acid composition of membrane lipids, whose changes were expected by the morphological alternation of cells, was not different under normal and hypotonic conditions. In addition, transcriptome analysis revealed the expression was reduced for genes related to actin cytoskeleton and increased for genes involved in ATP synthesis in mitochondria. Therefore, to adapt to the hypotonic stress, B. fuscoperpurea reduces the concentration of cellular substances to prevent cell swelling and accumulates energy by stopping cell division to survive in fresh water.

Free Research Field

海洋植物学