Related Experiment Video

Updated: Jul 14, 2026

Rapid Synthesis and Screening of Chemically Activated Transcription Factors with GFP-based Reporters
09:22

Rapid Synthesis and Screening of Chemically Activated Transcription Factors with GFP-based Reporters

Published on: November 26, 2013

Yeast HAP1 activator competes with the factor RC2 for binding to the upstream activation site UAS1 of the CYC1 gene

K Pfeifer, B Arcangioli, L Guarente

    Cell
    |April 10, 1987
    PubMed

    We show that the yeast HAP1 activator locus encodes a protein that binds in vitro to the upstream activation site, UAS1, of the CYC1 gene (iso-1-cytochrome c). Binding of wild-type HAP1 and truncated HAP1 derivatives to UAS1 is evident in crudely fractionated yeast extracts using the gel electrophoresis DNA binding assay. The binding of HAP1 in vitro, like the activity of UAS1 in vivo, is stimulated by heme. HAP1 binds to region B, one of two portions of UAS1 shown to be important by genetic analysis of the site. Surprisingly, HAP1 binds to the same sequence as a second factor, RC2. Both HAP1 and RC2 bind to the same side of the helix, and make similar but not identical major and minor groove contacts that span two full turns. An additional factor that binds to the second important part of UAS1, the region A factor (RAF), is also identified. A model depicting the interplay of HAP1, RC2, and RAF in the control of UAS1 is presented.

    More Related Videos

    Targeted in Situ Mutagenesis of Histone Genes in Budding Yeast08:48

    Targeted in Situ Mutagenesis of Histone Genes in Budding Yeast

    Published on: January 26, 2017

    ACT1-CUP1 Assays Determine the Substrate-Specific Sensitivities of Spliceosomal Mutants in Budding Yeast07:31

    ACT1-CUP1 Assays Determine the Substrate-Specific Sensitivities of Spliceosomal Mutants in Budding Yeast

    Published on: June 30, 2022

    Related Concept Videos

    Yeast Signaling01:28

    Yeast Signaling

    Yeasts are single-celled organisms, but unlike bacteria, they are eukaryotes (cells with a nucleus). Cell signaling in yeast is similar to signaling in other eukaryotic cells. A ligand, such as a protein or a small molecule released from a yeast cell, attaches to a receptor on the cell surface. The binding stimulates second-messenger kinases to activate or inactivate transcription factors that further regulate gene expression. Many of the yeast intracellular signaling cascades have similar...
    RNA Polymerase II Accessory Proteins02:36

    RNA Polymerase II Accessory Proteins

    Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
    Eukaryotic Transcription Inhibitors01:52

    Eukaryotic Transcription Inhibitors

    Certain biochemical processes, such as embryonic development and cell growth regulation, depend on the repression of specific genes. DNA binding proteins known as eukaryotic transcription inhibitors regulate the repression of gene expression in eukaryotes. The presence of these inhibitors at the required location and time in the cell is triggered by the presence of hormones and additional signals from other cells.
    Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
    Combinatorial Gene Control02:33

    Combinatorial Gene Control

    Combinatorial gene control is the synergistic action of several transcriptional factors to regulate the expression of a single gene. The absence of one or more of these factors may lead to a significant difference in the level of gene expression or repression.
    The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
    Separation of Sister Chromatids02:17

    Separation of Sister Chromatids

    At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
    At the onset of anaphase, separase, a proteolytic enzyme, is...
    Anaphase Promoting Complex00:50

    Anaphase Promoting Complex

    The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...