1.2(a) The Proteome & (b) Synthesis of Proteins Flashcards
What is the genome
The entire hereditary information encoded in an organism’s DNA
What is the preteome
The entire set of proteins expressed by a genome
Why is the proteome larger than the genome
Due to alternative RNA splicing
What are genes that do not code for proteins called
Non-coding RNA genes
Give example of non-coding RNA genes
Genes that are transcribed to produce tRNA, rRNA and RNA molecules that control expression of other genes
What are the factors that affect the set of proteins expressed by a given cell type
Metabolic activity of the cell
Cellular stress
Diseased versus healthy cells
The response to signalling molecule
What is the role of the endoplasmic reticulum
It forms a network of membrane tubules continuous with the nuclear membrane. It is also involved in the synthesis of lipids and proteins.
What does the smooth endoplasmic reticulum synthesise
Lipids
What does the rough endoplasmic reticulum synthesise
Proteins
What is the Golgi apparatus
A series of flattened membrane discs, this is where post translational modifications happen here.
What does the Golgi apparatus do
Packages proteins into membrane bound vesicles inside the cell before they are sent to their destination.
What are lysosomes
Membrane bound organelles containing a variety of hydrolases (enzymes) that digest proteins, lipids, nucleic acids and carbohydrates.
What is a vesicle
A structure within or outside a cell, consisting of a cytoplasm enclosed by a bilipid layer
What do vesicles do
Transport materials between membrane compartments
What are lipids
The building blocks of cells e.g., fats, oils and hormones
What are the 2 parts of the cytoplasm
Cytosol - the liquid of the cytoplasm
Ribosomes and the membrane bound organelles
Where does the synthesis of all proteins begin
cytosolic ribosomes
Where are cytosolic proteins found
The cytosol
Where are cytosolic proteins synthesised
The cytosolic ribosomes only (ribosomes NOT attached to the ER)
What are transmembrane proteins
Those that span the membrane
Where does the synthesis of cytosolic ribosomes start
The cytosolic ribosomes
Transmembrane proteins carry a signal sequence, what does this do,
They halt translation and directs the ribosome synthesising the protein to dock with the ER, forming the RER
What is a signal sequence
A short stretch of amino acids at one end of the polypeptide that determines the eventual location of a protein in a cell
What happens as proteins move through the Golgi Apparatus
They undergo post-translational modifications
