title: The role of aldehyde dehydrogenase and hsp70 in suppression of white spot syndrome virus replication at high temperature.
abstract: High temperature (32 to 33°C) has been shown to reduce mortality in white spot syndrome virus (WSSV)-infected shrimps, but the mechanism still remains unclear. Here we show that in WSSV-infected shrimps cultured at 32°C, transcriptional levels of representative immediate-early, early, and late genes were initially higher than those at 25°C. However, neither the IE1 nor VP28 protein was detected at 32°C, suggesting that high temperature might inhibit WSSV protein synthesis. Two-dimensional gel electrophoresis analysis revealed two proteins, NAD-dependent aldehyde dehydrogenase (ALDH) and the proteasome alpha 4 subunit (proteasome α4), that were markedly upregulated in WSSV-infected shrimps at 32°C. Reverse transcription-PCR (RT-PCR) analysis of members of the heat shock protein family also showed that hsp70 was upregulated at 32°C. When aldh, proteasome α4, and hsp70 were knocked down by double-stranded RNA interference and shrimps were challenged with WSSV, the aldh and hsp70 knockdown shrimps became severely infected at 32°C, while the proteasome α4 knockdown shrimps remained uninfected. Our results therefore suggest that ALDH and Hsp70 both play an important role in the inhibition of WSSV replication at high temperature.
authors.affiliation: Institute of Zoology, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan, Republic of China.
authors.forename: Ying-Ru
authors.initials: YR
authors.lastname: Lin
authors.forename: Hsiao-Chun
authors.initials: HC
authors.lastname: Hung
authors.forename: Jiann-Horng
authors.initials: JH
authors.lastname: Leu
authors.forename: Hao-Ching
authors.initials: HC
authors.lastname: Wang
authors.forename: Guang-Hsiung
authors.initials: GH
authors.lastname: Kou
authors.forename: Chu-Fang
authors.initials: CF
authors.lastname: Lo
mesh_terms: D000444:Aldehyde Dehydrogenase / Q000378:metabolism*; D000818:Animals; D015180:Electrophoresis, Gel, Two-Dimensional; D020869:Gene Expression Profiling; D055785:Gene Knockdown Techniques; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D033561:Penaeidae / Q000821:virology*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D021122:Protein Subunits / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013696:Temperature; D014764:Viral Proteins / Q000378:metabolism; D014779:Virus Replication / Q000528:radiation effects*; D046848:White spot syndrome virus 1 / Q000502:physiology* / Q000528:radiation effects*
chemical_list: D018840:HSP70 Heat-Shock Proteins; D021122:Protein Subunits; D014764:Viral Proteins; D000444:Aldehyde Dehydrogenase; D046988:Proteasome Endopeptidase Complex