12 - Protein synthesis Flashcards
(20 cards)
What is a proteome?
All of the proteins produced in a cell
What is proteomics?
The study of the proteins in a cell
What are the shape, properties, and functions of a cell determined by?
The specific arrangement of amino acids
What is genetic code?
The specific arrangement of nucleotides in DNA/RNA, which determines the amino acid sequence of a specific protein
What is gene expression?
The production of proteins from information stored in the DNA
What is central dogma?
The directional flow of information, from DNA -> RNA -> Protein
Where does transcription occur?
In the nucleus
What occurs during transcription? (easy version)
A copy of a gene is produced
DNA -> mRNA
Where does translation occur?
In the cytoplasm
What occurs during translation? (Easy ver)
The information copied during transcription is converted into a protein
mRNA -> protein
What is the start codon?
AUG
Methionine
How does mRNA leave the nucleus after transcription?
Through the nuclear pores
How many possible codons are there in RNA?
64
How many naturally-occuring amino acids are there?
20
What does it mean for DNA to be degenerate?
One amino acid can have multiple codons
Which three codes specify the end of a peptide chain?
UAA
UAG
UGA
What is post-translational modification?
The chemical modification of a protein after translation. Can involve sticking on extra functional groups, or chopping bits off
What is a modification that can be used to control the behaviour of a protein?
Phosphorylation
What occurs during transcription?
Transcription factors initiate
RNA polymerase enzyme “unzips” 2 strands of DNA (coding & template)
RNA polymerase binds at promoter region
Genetic information is copied from the template strand, forming mRNA
RNA polymerase catalyses formation of complementary mRNA strands, following A-U C-G pattern
Codons signal stopping point
mRNA exits nucleus through nuclear pores
What occurs during translation?
mRNA carries genetic information to ribosomes
Transcription machinery in ribosomes reads mRNA sequences in lots of 3 nucleotides (codons), starting at the start codon (AUG)
As each codon is read, tRNA with complementary sequences (anticodons) binds to each codon.
tRNA carries specific proteins, which are joined together with peptide bonds
