These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Hoechst 33342-induced apoptosis is associated with intracellular accumulation of E2F-1 protein in BC3H-1 myocytes and HL-60 cells.
    Author: Zhang X, Kiechle FL.
    Journal: Arch Pathol Lab Med; 2001 Jan; 125(1):99-104. PubMed ID: 11151061.
    Abstract:
    CONTEXT: Hoechst 33342 induces apoptosis, inhibits topoisomerase I, and disrupts TATA box-binding protein/TATA box element binding in BC3H-1 myocytes and HL-60 cells. In contrast, Hoechst 33258 does not have any of these actions. OBJECTIVE: To determine if Hoechst 33342 or Hoechst 33258 treatment of BC3H-1 myocytes or HL-60 cells is associated with the intracellular accumulation of the nuclear transcription factor E2F-1, known to induce apoptosis. METHODS: The gel mobility shift assay was used to study the effect of the 2 compounds on the binding capacity of nuclear proteins extracted from the 2 cell lines to a 30-base pair double-stranded oligonucleotide that contained an E2F-1-binding element. The DNA sequence of the protein-binding region was determined by the protection footprinting method and the Maxam-Gilbert guanosine plus adenosine chemical sequencing reaction. RESULTS: Nuclear extracts from each cell line treated with 26.7 micromol/L Hoechst 33342 or Hoechst 33258 for 3 to 24 hours were incubated with [32P]-labeled 30-base pair oligonucleotide (5'GGCGCGGAGACTTGGAGAAATTTGGCGCGG3'). Three protein and DNA bands were altered by Hoechst 33342, but not by Hoechst 33258: band I, increased, then decreased in both cell lines; band II (2 adjacent bands) markedly decreased in both cell lines; band III markedly increased only in HL-60 cells. Footprinting and sequencing demonstrated that the nuclear protein-binding sequence was TTTGGCGC, an E2F-1 binding site. Hoechst 33342 treatment increased the concentration of E2F-1 protein after a 3-hour incubation in both cell lines. CONCLUSION: Hoechst 33342-induced apoptosis is associated with intracellular accumulation of E2F-1 protein, another step in this specific apoptotic pathway.
    [Abstract] [Full Text] [Related] [New Search]