Transcriptional Response to Acute Thermal Exposure in Juvenile Chinook Salmon Determined by RNAseq.
Thermal exposure is a serious and growing challenge facing fish species worldwide. Chinook salmon (Oncorhynchus tshawytscha) living in the southern portion of their native range are particularly likely to encounter warmer water due to a confluence of factors. River alterations have increased the likelihood that juveniles will be exposed to warm water temperatures during their freshwater life stage, which can negatively impact survival, growth, and development and pose a threat to dwindling salmon populations. To better understand how acute thermal exposure affects the biology of salmon, we performed a transcriptional analysis of gill tissue from Chinook salmon juveniles reared at 12° and exposed acutely to water temperatures ranging from ideal to potentially lethal (12° to 25°). Reverse-transcribed RNA libraries were sequenced on the Illumina HiSeq2000 platform and a de novo reference transcriptome was created. Differentially expressed transcripts were annotated using Blast2GO and relevant gene clusters were identified. In addition to a high degree of downregulation of a wide range of genes, we found upregulation of genes involved in protein folding/rescue, protein degradation, cell death, oxidative stress, metabolism, inflammation/immunity, transcription/translation, ion transport, cell cycle/growth, cell signaling, cellular trafficking, and structure/cytoskeleton. These results demonstrate the complex multi-modal cellular response to thermal stress in juvenile salmon.
Department of Animal Science, University of California, Davis, California 95616 kmtomalty@ucdavis.edu.
Katharine M H
KM
Tomalty
Department of Animal Science, University of California, Davis, California 95616.
Mariah H
MH
Meek
Department of Animal Science, University of California, Davis, California 95616.
Molly R
MR
Stephens
Department of Animal Science, University of California, Davis, California 95616.
Gonzalo
G
Rincón
Department of Wildlife, Fish, and Conservation Biology, University of California, Davis, California 95616.
Nann A
NA
Fangue
Department of Animal Science, University of California, Davis, California 95616.
Bernie P
BP
May
Department of Animal Science, University of California, Davis, California 95616.
Melinda R
MR
Baerwald
D000818:Animals; D015536:Down-Regulation; D029941:Fish Proteins / Q000235:genetics; D005880:Gills / Q000378:metabolism; D011489:Protein Denaturation; D012313:RNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012474:Salmon / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D017423:Sequence Analysis, RNA; D013696:Temperature; D059467:Transcriptome; D015854:Up-Regulation
D029941:Fish Proteins; D012313:RNA
Illumina; Oncorhynchus tshawytscha; gene discovery; thermal tolerance