Title page for etd-1120108-183121


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URN etd-1120108-183121
Author Yuan-ting Hsu
Author's Email Address No Public.
Statistics This thesis had been viewed 5583 times. Download 23 times.
Department Marine Biology
Year 2008
Semester 1
Degree Ph.D.
Type of Document
Language zh-TW.Big5 Chinese
Title Signal derived from photosynthic electron transport regulates the expression of methionine sulfoxide reductase (Msr) gene in the green macroalga Ulva fasciata Delile
Date of Defense 2008-11-13
Page Count 136
Keyword
  • DCMU
  • Ulva fasciata
  • methionine sulfoxide reductase
  • electron transport chain
  • Antimycin A
  • hydroxylamine
  • Light
  • stigmatellin
  • SHAM
  • DCPIP
  • DBMIB
  • Abstract This study has investigated the involvement of photosynthetic electron transport chain on the regulation of gene expression of methionine sulfoxide reductase (UfMSR) in the marine macroalga Ulva fasciata Delile.UfMSRA is from copper stress and UfMSRB ir from hypersalinity stress. UfMSRA is similar to Arabidopsis AtMSRA4 and UfMSRB is similar to AtMSRB1. UfMSRA is specific to the MetSO S-enantiomer and UfMSRB catalytically reduces the MetSO R-enantiomer. Both enzymes are required, since in the cell oxidation of Met residues at the sulfur atom results in a racemic mixture of the two stereoisomers. UfMSRA and UfMSRB transcripts were increased by white light, blue light and red light with the maximum at 1 h following a decline, but kept constant in the dark. The magnitude of UfMSRA and UfMSRB transcript increase showed a positive linear correlation to increasing light intensity from 0-1200 u mole·m-2·s-1. The treatment with linear electron transport
    chain inhibitors, hydroxylamine, 3-(3,4-dichlorophenyl) -1,1-dimethylurea (DCMU),
    2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB) and stigmatellin,
    effectively inhibited PS II activity under 300 u mole·m-2·s-1 irradiance. DBMIB and
    stigmatellin can increase UfMSRA transcript that was reversed by
    2,6-dichlorophenolindophenol (DCPIP), a PS I electron donor. It indicates that the
    block of electron transport of the downstream of cytochrome b6f indeuces UfMSRA
    gene expression. Hydroxylamine, DCMU and DBMIB decreased UfMSRB transcript
    that was not reversed by DCPIP while stigmatellin increased UfMSRB mRNA level,
    reflecting a role of reduced state with Qo site located at cytochrome b6f on the
    induction of UfMSRB gene expression. The cyclic electron transport chain inhibitors,
    antimycin A that inhibited photosynthetic electron transport, can inhibit the increase
    of UfMSRA and UfMSRB transcripts by irradiance. UfMSRA and UfMSRB gene
    expression were both modulated by cyclic electron transport chain and linear electron
    transport chain. These results reveal that photosynthetic electron transport chain
    modulates UfMSRA and UfMSRB gene expression by change its redox state.
    Advisory Committee
  • Zin-Huang Liu - chair
  • Hsien-Jung Chen - co-chair
  • Tse-Min Lee - advisor
  • Files
  • etd-1120108-183121.pdf
  • indicate in-campus access in a year and off_campus not accessible
    Date of Submission 2008-11-20

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