Related Experiment Video
Updated: Feb 5, 2026
12:41
Measuring Replicative Life Span in the Budding Yeast
Published on: June 25, 2009
21.3K
The TORC1-Nem1/Spo7-Pah1/lipin axis regulates microautophagy induction in budding yeast
Muhammad Arifur Rahman1, Mashu Terasawa2, Md Golam Mostofa1
1Graduate School of Science and Technology, Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, 422-8021, Japan.
Biochemical and Biophysical Research Communications
|September 12, 2018
Summary
Nutrient starvation inactivates the target of rapamycin complex 1 (TORC1) kinase, inducing both macroautophagy and microautophagy. This process requires the Nem1/Spo7-Pah1 pathway and Vps27, revealing a master regulator for yeast autophagy.
Area of Science:
- Cellular biology
- Molecular biology
- Yeast genetics
Background:
- Nutrient starvation and target of rapamycin complex 1 (TORC1) inhibition are known inducers of macroautophagy.
- Macroautophagy is a lipid-consuming cellular process.
- The regulation of microautophagy by TORC1 has been debated.
Purpose of the Study:
- To investigate the role of TORC1 signaling in the regulation of microautophagy.
- To identify key proteins and pathways involved in TORC1-mediated microautophagy induction.
Main Methods:
- Utilized budding yeast Saccharomyces cerevisiae as a model organism.
- Investigated the requirement of specific genes (Vps27, Atg1, Atg7, Atg8) in microautophagy induction.
- Examined the role of the Nem1/Spo7-Pah1 axis in TORC1 inactivation-induced microautophagy.
Main Results:
- TORC1 inactivation was found to induce microautophagy in budding yeast.
- Vps27 was identified as essential for TORC1 inactivation-induced microautophagy, while Atg1, Atg7, and Atg8 were not.
- The Nem1/Spo7-Pah1 protein phosphatase pathway was critical for microautophagy induction.
Conclusions:
- The TORC1 signaling pathway, through the Nem1/Spo7-Pah1 axis, acts as a master regulator of both macroautophagy and microautophagy in budding yeast.
- This study elucidates a conserved regulatory mechanism for different types of autophagy in response to nutrient availability.
Related Concept Videos
01:28Yeast Signaling
17.3K
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...
17.3K
01:37Hypothalamic-Pituitary Axis
66.2K
The response to stress—be it physical or psychological, acute or chronic—involves activation of the Hypothalamic-Pituitary-Adrenal (HPA) axis. The HPA axis is part of the neuroendocrine system because it involves both neuronal and hormonal communication. Its function is to regulate homeostatic systems—metabolic, cardiovascular, and immune—providing the necessary means to respond to a stressor.
66.2K
00:49The Tongue and Taste Buds
41.1K
The surface of the tongue is covered with various small bumps called papillae, which either distribute what has been ingested (filiform papillae) or contain the sensory taste (or gustatory) receptor cells (fungiform, circumvallate, and foliate papillae). Embedded within each taste-related papilla are the taste buds—clusters of 30 to 100 gustatory receptor cells.
41.1K
01:20Taste Buds and Receptors
5.3K
Gustation, or the sense of taste, is intrinsically linked to the anatomical structures located on the tongue. This organ's surface, along with the entirety of the oral cavity, is adorned with stratified squamous epithelium. Evident on the tongue are elevated structures known as papillae (singular = papilla), which house the mechanisms for the transduction of gustatory stimuli. Four distinct types of papillae exist, each identified by their unique morphological attributes: the circumvallate,...
5.3K
01:16Perpendicular-Axis Theorem
4.6K
The perpendicular-axis theorem states that the moment of inertia of a planar object about an axis perpendicular to its plane is equal to the sum of the moments of inertia about two mutually perpendicular concurrent axes lying in the plane of the body.
Consider a circular disc of mass M and radius R lying along an x-y plane. The origin lies at the center of the disc, and the z-axis is perpendicular to the disc's plane. All three axes coincide at the disc's center. The moment of inertia of this...
Consider a circular disc of mass M and radius R lying along an x-y plane. The origin lies at the center of the disc, and the z-axis is perpendicular to the disc's plane. All three axes coincide at the disc's center. The moment of inertia of this...
4.6K
01:06Parallel-axis Theorem
8.3K
The parallel-axis theorem provides a convenient and quick method of finding the moment of inertia of an object about an axis parallel to the axis passing through its center of mass. Consider a thin rod as an example. There is a striking similarity between the process of finding the moment of inertia of a thin rod about an axis through its middle, where the center of mass lies, and about an axis through its end using the conventional method. In the conventional method, the concept of linear mass...
8.3K