Related Experiment Video
Updated: Jun 17, 2026
09:04
Yeast Colony Embedding Method
Published on: March 22, 2011
The Rim101p/PacC pathway and alkaline pH regulate pattern formation in yeast colonies
Sarah Piccirillo1, Melissa G White, Jeffrey C Murphy
1Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri, Kansas City, Missouri 64110, USA.
Genetics
|December 30, 2009
Summary
Yeast colonies form distinct layers of sporulating cells, driven by cell-to-cell pH signals. The Rim101p/PacC pathway responds to alkaline pH, mediating this colony patterning for efficient spore formation.
Area of Science:
- Microbiology
- Developmental Biology
- Yeast Genetics
Background:
- Multicellular organisms use cell signals for pattern formation, but fungal community organization is less understood.
- Saccharomyces cerevisiae colonies exhibit organized patterns of sporulating and non-sporulating cells.
Purpose of the Study:
- To investigate the mechanisms of cell-to-cell signaling in yeast colony patterning.
- To identify the signals and pathways involved in fungal community organization.
Main Methods:
- Analysis of sporulation patterns in Saccharomyces cerevisiae colonies.
- Gene expression analysis of sporulation activators (IME1, IME2).
- Construction and analysis of chimeric colonies and meiotic-arrest mutants.
Main Results:
- Colonies displayed sharply divided layers of sporulating cells, originating in the interior and expanding upwards.
- Sporulation activators IME1 and IME2 were transcribed in overlapping regions corresponding to initial sporulation.
- Alkaline pH, mediated by the Rim101p/PacC pathway, was identified as a key cell-to-cell signal influencing sporulation patterns.
Conclusions:
- Cell-to-cell pH signaling via the Rim101 pathway is crucial for yeast colony patterning.
- This signaling mechanism, potentially combined with nutrient gradients, facilitates efficient spore formation and dispersal.
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...
01:31Mechanism of Lamellipodia Formation
Cells migrating in response to external stimuli form lamellipodia, which are thin membrane protrusions supported by a mesh of linked, branched, or unbranched actin filaments. These actin filaments interact with myosin motor proteins, creating the dynamic actomyosin complex within the cytoskeleton. Contractility, or the ability to generate contractile stress, is inherent to the actomyosin complex. It helps cells detect the stiffness of the surrounding ECM and exert contractile force for...
01:21Cell Polarization by Rho Proteins
Cell polarity is the asymmetric distribution of cellular and membrane components, making one side of the cell different from the other. This polarity is essential to many processes such as embryogenesis, axon migration, glucose transport across epithelial cells, and directional cell migration. A migrating cell responds to intracellular or extracellular signals via molecular cascades that reorganize the actin cytoskeleton to establish this polarity. In these cells, the Rho family proteins Cdc42,...
02:36Cells Coordinate Growth and Proliferation
Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...
01:17Gene Regulation During Sporulation
Sporulation is a complex developmental process that allows certain Gram-positive bacteria, such as Bacillus subtilis and Clostridium species, to survive extreme environmental conditions. This process is tightly regulated by a series of signaling cascades and transcriptional controls, ensuring the formation of a highly resistant endospore.Sporulation is triggered by unfavorable conditions, such as nutrient depletion, and is governed by a phosphorelay system. One of the sensor kinases, such as...
01:39Mechanism of Filopodia Formation
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...