Week Number: 13
Seminar Date: Wednesday 1st November
Time: 10am-11am
Module: Cell Biology BI503
Tubulin and microtubules
Today we are going to cover microtubules and how they’re made.
Image of a mitotic cell
This shows long fibers (microtubules) leading into the central part and thicker bundles of
microtubules forming the spindle ball bundles. The spindle ball body is where the
microtubules are born, the asp microtubules help position the spindle ball body.
Microtubular assemblies
Microtubule dynamics highlighted by GFP-EB1, bind to the GTP cap of growing
microtubules. All the white blobs race around inside the cytoplasm, these white blobs mark
the ends of microtubules. Microtubule networks in the cytoplasm are highly dynamic and are
constantly being made and used.
Microtubule and endoplasmic reticulum dynamics at the edge of the cell, note the dynamic
interplay between these systems. The red lines represent microtubules spreading to the
leading edge of the cell and then shrinking rapidly away. This is a fundamental property
of microtubules.
The green lines represent the endoplasmic reticulum. Most organelles within the cells are
being transported along the microtubules, this is why the red and green lines interconnect.
These are train track structures transporting material throughout the cell.
Microtubule dependent transport/movement in cells
One of the main roles of microtubules is to transport membrane vesicles and organelles
through the cytoplasm. For example, Messenger RNA. Microtubules interface with actin
filaments to form a mesh work at the edge of the cell. The motor proteins bind to the
microtubules, using the microtubular motor proteins and the actin filaments.
The transport process will be covered in the next lecture.
Fundamental principles of microtubules.
Every microtubule filament is made of two proteins (heterodimer):
1. Alpha tubulin - this subunit is exposed on the - end of the microtubule.
2. Beta tubulin – this subunit is exposed on the + end of the microtubule.
1
Seminar Date: Wednesday 1st November
Time: 10am-11am
Module: Cell Biology BI503
Tubulin and microtubules
Today we are going to cover microtubules and how they’re made.
Image of a mitotic cell
This shows long fibers (microtubules) leading into the central part and thicker bundles of
microtubules forming the spindle ball bundles. The spindle ball body is where the
microtubules are born, the asp microtubules help position the spindle ball body.
Microtubular assemblies
Microtubule dynamics highlighted by GFP-EB1, bind to the GTP cap of growing
microtubules. All the white blobs race around inside the cytoplasm, these white blobs mark
the ends of microtubules. Microtubule networks in the cytoplasm are highly dynamic and are
constantly being made and used.
Microtubule and endoplasmic reticulum dynamics at the edge of the cell, note the dynamic
interplay between these systems. The red lines represent microtubules spreading to the
leading edge of the cell and then shrinking rapidly away. This is a fundamental property
of microtubules.
The green lines represent the endoplasmic reticulum. Most organelles within the cells are
being transported along the microtubules, this is why the red and green lines interconnect.
These are train track structures transporting material throughout the cell.
Microtubule dependent transport/movement in cells
One of the main roles of microtubules is to transport membrane vesicles and organelles
through the cytoplasm. For example, Messenger RNA. Microtubules interface with actin
filaments to form a mesh work at the edge of the cell. The motor proteins bind to the
microtubules, using the microtubular motor proteins and the actin filaments.
The transport process will be covered in the next lecture.
Fundamental principles of microtubules.
Every microtubule filament is made of two proteins (heterodimer):
1. Alpha tubulin - this subunit is exposed on the - end of the microtubule.
2. Beta tubulin – this subunit is exposed on the + end of the microtubule.
1
