Related Experiment Video
Updated: Jun 30, 2025
10:23
High-resolution Imaging and Analysis of Individual Astral Microtubule Dynamics in Budding Yeast
Published on: April 20, 2017
9.5K
Fungal microtubule organizing centers are evolutionarily unstable structures.
Adam Grazzini1, Ann M Cavanaugh1
1Department of Biology, Creighton University, Omaha, Nebraska, USA.
Fungal Genetics and Biology : FG & B
|March 14, 2024
Summary
Fungal microtubule organizing centers (MTOCs) lose evolutionary stability when cilia are lost. Despite rapid changes in MTOC protein composition and sequences, interacting proteins stabilize each other, maintaining essential functions.
Area of Science:
- Evolutionary biology
- Cell biology
- Mycology
Background:
- Microtubule organizing centers (MTOCs) are crucial for eukaryotic cell structure, often dictated by cilia formation.
- Fungal MTOCs exhibit unique evolutionary dynamics, particularly in relation to cilia presence or absence.
Purpose of the Study:
- To investigate the evolutionary stability of fungal MTOCs in correlation with cilia formation.
- To analyze the conservation of protein composition and sequences within fungal MTOCs.
- To understand how protein-protein interactions influence evolutionary rates in fungal MTOCs.
Main Methods:
- Utilized iterative search algorithms to identify homologous proteins in fungal MTOCs.
- Calculated site-specific rates of evolutionary change for broadly distributed MTOC proteins.
- Analyzed the impact of structural interfaces on protein residue evolutionary rates.
Main Results:
- Loss of cilia correlates with reduced evolutionary stability of fungal MTOCs.
- Fungal MTOC protein composition and sequences are poorly conserved across the fungal kingdom.
- Protein-protein interactions within MTOCs can stabilize interacting partners, counteracting rapid sequence evolution.
Conclusions:
- Fungal MTOCs undergo rapid evolutionary changes in protein content and sequence.
- Despite sequence variability, structural interactions among MTOC proteins provide stability.
- Understanding these dynamics is key to comprehending how cellular functional needs shape evolution.
Related Concept Videos
02:17Microtubule Instability
5.1K
Microtubules are hollow cylindrical filaments having a diameter of approximately 25 nm and a length that varies from 200 nm to 25 μm. GTP-bound tubulin subunits form αβ-heterodimers for microtubule assembly. These core building blocks interact longitudinally, polymerizing into protofilaments. The protofilaments then interact with one another through lateral bonding forces to form stable cylindrical microtubules. These cylindrical filaments are dynamic as they undergo repeated...
5.1K
01:45Destabilization of Microtubules
2.7K
The destabilization of microtubules can occur during different stages of the microtubule lifecycle, such as nucleation or elongation. It can take place at either end of the microtubule or in the microtubule lattices as a whole. The lifespan of individual microtubules within a cell varies according to the cell type and stage of the cell cycle. During interphase, the lifespan of the microtubule is about 30 minutes, while during cell division, it is about 15 minutes. In axonal microtubules of...
2.7K
01:23Microtubule Formation
5.7K
Microtubules are dynamic structures that undergo continuous assembly and disassembly. They originate from specialized multi-protein complexes known as microtubule organizing centers or MTOCs. Within the MTOC, the point of origin of the microtubule is known as the minus end, while the end radiating outward is the plus end. Microtubules serve two primary functions — the organization of spindle complexes to separate sister chromatids during mitotic or meiotic cell division and the formation...
5.7K
01:10Drugs that Destabilize Microtubules
2.0K
Microtubules are dynamic structures and can be regulated by microtubule targeting agents (MTAs). Microtubule destabilizing drugs are a class of MTAs that destabilize and prevent microtubules' polymerization. Both natural and synthetic chemicals can be found under this class of drugs. Vincristine and vinblastine, two vinca alkaloids, and colchicine were among the first to be discovered. These drugs can affect cells in various ways, either by inducing a change in cell morphology, preventing...
2.0K
02:50Spindle Assembly
3.6K
Spindle assembly occurs through three, often coexisting, pathways – the centrosome-mediated pathway, the chromatin-mediated pathway, and the microtubule-mediated pathway – collectively contributing to form a robust spindle apparatus.
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a...
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a...
3.6K
01:39Anaphase A and B
4.1K
Microtubules form through the end-to-end polymerization of tubulin heterodimers. Kinetochore microtubules originate from the spindle poles, and their plus-ends connect with the kinetochores on sister-chromatids. Ndc80 protein complexes, present on the kinetochore, form low-affinity links with the plus end of these kinetochore microtubules.
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
4.1K