PMT Flashcards
What is central dogma?
The idea genetic information flows in one direction. The idea that DNA is transcribed into RNA then the RNA is translated into a protein.
What is the post translational modification (PTM)?
Covalent addition onto/cleavage of protein after protein biosynthesis.
What is the importance of PTM?
Important component of cell signalling.
Increases diversity of proteins.
The main example of why PTM is important?
Pluripotent Stem Cells (PSC).
What are pluripotent stem cells (PSC)?
Cells which are able to self renew and differentiate into 1 of 3 groups.
What are the 3 groups that PSC can differentiate into?
- Endoderm
- Mesoderm
- Ectoderm
What are endoderms?
They form gastro-internal and respiratory tracts.
What are ectoderms?
Make up skin and nervous system.
What are mesoderms?
Germ layer present in animal embryos which later become highly specialised cells.
How is PTM linked to peuripotent stem cells?
The direction and destination of these cells is controlled at a PTM level.
What are the different types of PTM?
Hydroxylation
Methylation
Lipidation
Acetylation
Disulphide Bond
SUMOylation
Ubiquitination
Glycosylation
Phosphorylation
What is phosphorylation?
Adds a phosphate to serine, threonine or tyrosine.
What is glycosylation?
Attaches a sugar, usually to an “N” or “O” in an amino acid side chain.
What is ubiquitination?
Adds ubiquitin to lysine residue of a target protein for degradation.
What is a SUMOylation?
Adds a small protein SUMO (small ubiquitin-like modifier) to a target protein.
What is a disulphide bond?
Covalently links to “S” atoms of two different cysteine residues.
What is acetylation?
Adds an acetyl group to an N-terminus of a protein or at lysine residue.
What is lipidation?
Attaches a lipid, such as a fatty acid, to a protein chain.
What is methylation?
Adds a methyl group, usually at lysine or arginine residues.
What is hydroxylation?
Attaches a hydroxyl group (OH-) to a side chain of a protein.
How does cleavage promote insulin production?
- Translation and translocation
- Folding, oxidation and signal peptide cleavage
- ER export, Golgi transport vesicle packaging
- Protease cleavage liberates C-peptide
- Carboxypeptidase E produces mature insulin.
What is translocation?
Movement of an item from one place to another.