Biomaterial Database

Regulation of hsp70 induction in thermotolerant HeLa cells. 1993

T Hatayama, and Y Asai, and T Wakatsuki, and T Kitamura, and H Imahara

Department of Biochemistry, Kyoto Pharmaceutical University, Japan.

Upon exposure to heat shock, non-thermotolerant (NT) HeLa cells transiently synthesize a large amount of 70-kDa heat-shock protein (hsp70), whereas thermotolerant (TT) cells synthesize a small amount of hsp70. When the hsp70 mRNA of HeLa cells was analyzed, it became apparent that hsp70 mRNA in TT cells did not increase following heat shock, whereas hsp70 mRNA in NT cells did increase dramatically. A further analysis of the activation of the heat-shock transcription factor (HSF) showed that significant activation of HSF was observed immediately after heat shock in both NT and TT cells. However, activated HSF was rapidly repressed in the TT cells, but not in the NT cells. Thus, the decreased induction of hsp70 synthesis observed in the TT HeLa cells may be due to the immediate repression of activated cellular HSF, which probably results in the reduced induction of hsp70 mRNA. The hsp70 content in the TT cells was usually higher than in the NT cells. However, after heat-shock treatment, the hsp70 content of the NT cells increased to nearly the level of the TT cells concomitant with the repression of hsp70 synthesis. The association of activated HSF with hsp70 was observed in both NT and TT cells, and the amount of HSF-hsp70 complex within the cell increased in proportion to the increase in hsp70 in the cells. These findings strongly suggest that the activity of HSF is negatively regulated by the intracellular content of hsp70 in these cells. Furthermore, in vitro experiments on the activation of HSF suggest that HSFs of NT and TT cells may have different properties, or an unknown factor may exist which regulates HSF activation in these cells.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D002457	Cell Extracts	Preparations of cell constituents or subcellular materials, isolates, or substances.	Cell Extract,Extract, Cell,Extracts, Cell
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D006360	Heat-Shock Proteins	Proteins which are synthesized in eukaryotic organisms and bacteria in response to hyperthermia and other environmental stresses. They increase thermal tolerance and perform functions essential to cell survival under these conditions.	Stress Protein,Stress Proteins,Heat-Shock Protein,Heat Shock Protein,Heat Shock Proteins,Protein, Stress
D006367	HeLa Cells	The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for, among other things, VIRUS CULTIVATION and PRECLINICAL DRUG EVALUATION assays.	Cell, HeLa,Cells, HeLa,HeLa Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D012333	RNA, Messenger	RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.	Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated
D014157	Transcription Factors	Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.	Transcription Factor,Factor, Transcription,Factors, Transcription