Cilia and Flagella
Microtubule Structure
- Alpha tubulin (purple)
- Beta tubulin (blue)
- Thirteen pro-filaments, comprised of tubulin dimers,
arrange to form cylindrical microtubule
- Dynamic process of growth & shrinkage
- Mediated by GTP hydrolysis
Microtubule structure:
- Alpha tubulin (purple)
- Beta tubulin (blue)
- Thirteen pro-filaments, comprised of tubulin dimers,
arrange to form cylindrical microtubule
- Dynamic process of growth and shrinkage
Microtubule organisation:The big green lines are
microtubules, which originate from the MTOC.
Microtubules can have three structures:
1. O singlets in cytoplasm & mitotic spindles
2. OO doublets in cilia & flagella
3. OOO triplets in centrioles & basal bodies
, Centrioles and the Centrosome
- In many cells, microtubules grow out from a centrosome near the nucleus
- The centrosome is a “microtubule- organizing center”
- In animal cells, the centrosome has a pair of centrioles, each with nine triplets of
microtubules arranged in a ring
- Do not confuse centromere with centrosome: the centromere is a region of the
chromosome, while the centrosome is a microtubule-organizing centre.
Microtubules – role in cell cycle
- Mitosis – partition of replicated chromosomes
- Involves the assembly and disassembly of a key microtubule structure – mitotic
apparatus or mitotic spindle
Microtubule organisation:
The big green lines are microtubules, which all originate from the MTOC.
Cell cycle:
Microtubule Structure
- Alpha tubulin (purple)
- Beta tubulin (blue)
- Thirteen pro-filaments, comprised of tubulin dimers,
arrange to form cylindrical microtubule
- Dynamic process of growth & shrinkage
- Mediated by GTP hydrolysis
Microtubule structure:
- Alpha tubulin (purple)
- Beta tubulin (blue)
- Thirteen pro-filaments, comprised of tubulin dimers,
arrange to form cylindrical microtubule
- Dynamic process of growth and shrinkage
Microtubule organisation:The big green lines are
microtubules, which originate from the MTOC.
Microtubules can have three structures:
1. O singlets in cytoplasm & mitotic spindles
2. OO doublets in cilia & flagella
3. OOO triplets in centrioles & basal bodies
, Centrioles and the Centrosome
- In many cells, microtubules grow out from a centrosome near the nucleus
- The centrosome is a “microtubule- organizing center”
- In animal cells, the centrosome has a pair of centrioles, each with nine triplets of
microtubules arranged in a ring
- Do not confuse centromere with centrosome: the centromere is a region of the
chromosome, while the centrosome is a microtubule-organizing centre.
Microtubules – role in cell cycle
- Mitosis – partition of replicated chromosomes
- Involves the assembly and disassembly of a key microtubule structure – mitotic
apparatus or mitotic spindle
Microtubule organisation:
The big green lines are microtubules, which all originate from the MTOC.
Cell cycle:
