Related Experiment Video
Updated: Aug 3, 2026
04:36
Assay for Adhesion and Agar Invasion in S. cerevisiae
Published on: November 8, 2006
Combinatorial control required for the specificity of yeast MAPK signaling
1Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA.
Science (New York, N.Y.)
|February 28, 1997
Summary
In yeast, the transcription factors Ste12 and Tec1 cooperate to control distinct developmental programs. Their interaction with filamentation and invasion response elements (FREs) ensures specific responses to mitogen-activated protein kinase (MAPK) signaling.
Area of Science:
- Molecular Biology
- Yeast Genetics
- Cellular Signaling
Background:
- Mitogen-activated protein kinase (MAPK) signaling pathways regulate diverse cellular processes in yeast, including mating, invasion, and pseudohyphal development.
- The transcription factor Ste12 is a key downstream component essential for these distinct developmental programs.
- The precise mechanisms ensuring developmental specificity within these programs remain incompletely understood.
Purpose of the Study:
- To elucidate the molecular mechanisms underlying developmental specificity in yeast MAPK signaling.
- To investigate the role of the transcription factor Tec1 in cooperating with Ste12.
- To characterize the function of filamentation and invasion response elements (FREs) in regulating gene expression.
Main Methods:
- Biochemical analysis of transcription factor binding using purified Ste12 and Tec1 derivatives.
- Identification and characterization of enhancer elements (FREs) in target gene promoters.
- Analysis of gene expression patterns in response to MAPK signaling components.
Main Results:
- Tec1, a TEA/ATTS family transcription factor, cooperates with Ste12 to confer developmental specificity.
- Ste12 and Tec1 bind cooperatively to specific DNA sequences known as FREs.
- FREs are crucial for programming transcription in response to MAPK signaling pathways controlling filamentous growth.
- An FRE within the TEC1 promoter forms a positive feedback loop essential for pseudohyphal development.
Conclusions:
- Cooperative binding of Ste12 and Tec1 to FREs is a critical mechanism for achieving developmental specificity in yeast MAPK signaling.
- The TEC1 promoter FRE establishes a positive feedback loop that reinforces pseudohyphal development.
- This study reveals a sophisticated regulatory network involving transcription factors and cis-regulatory elements in controlling complex cellular behaviors.
Related Concept Videos
01:28Yeast 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...
02:33Combinatorial 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...
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...
02:39Positive Regulator Molecules
Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
01:19Interactions Between Signaling Pathways
Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
01:07MAPK Signaling Cascades
Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
01:25cAMP-dependent Protein Kinase Pathways
Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...