Neuronal cells show regulatory differences in the hsp70 gene response.
The synthesis of heat shock proteins (Hsps), encoded by heat shock genes, is increased in response to various stress stimuli. Hsps function as molecular chaperones, they dissociate cytotoxic stress-induced protein aggregates within cells and ensure improved survival. Induction of heat shock genes is mainly regulated at the transcriptional level. The stress responsive transcription factor, heat shock factor 1 (HSF1), is involved in the transcriptional induction of the heat shock genes. Our objective was to examine how hsp70 genes are regulated in different transformed and primary neurons upon exposure to elevated temperature. Our findings reveal that the Hsp70 response is regulated at the translational level in Neuro-2a neuroblastoma cells, while the IMR-32 neuroblastoma cells respond to stress by the classical HSF1-driven transcriptional regulatory mechanism. Primary rat hippocampal neurons show a lack of HSF1 and induction of the hsp70 gene. These observations suggest that neuronal cells display different hsp70 gene expression patterns which range from undetected response to transcriptional and posttranscriptional regulation during heat stress.
Kaarniranta
K
K
Department of Anatomy, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland. kaarnira@messi.uku.fi
Oksala
N
N
Karjalainen
H M
HM
Suuronen
T
T
Sistonen
L
L
Helminen
H J
HJ
Salminen
A
A
Lammi
M J
MJ
D000818:Animals; D002490:Central Nervous System / Q000378:metabolism* / Q000503:physiopathology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D000076249:Heat Shock Transcription Factors; D018869:Heat-Shock Response / Q000235:genetics*; D006624:Hippocampus / Q000378:metabolism / Q000503:physiopathology; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D051379:Mice; D009474:Neurons / Q000378:metabolism*; D010766:Phosphorylation; D014176:Protein Biosynthesis / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D013312:Stress, Physiological / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D014157:Transcription Factors; D014158:Transcription, Genetic / Q000502:physiology; D015533:Transcriptional Activation / Q000502:physiology; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000502:physiology
D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D018840:HSP70 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; C000619709:Hsf1 protein, rat; D012333:RNA, Messenger; D014157:Transcription Factors