Gene Expression and Proteins Flashcards
A gene is transcribed by what enzyme?
RNA polymerase
RNA polymerase moves along antisense DNA in what direction?
3’ to 5’
RNA polymerase adds nucleotides to which end of a growing RNA chain?
3’
What are transcription factors? Where would they bind on a gene?
Transcription factors regulate gene transription
They bind to either promoter regions or regulatory sequence regions
What are introns and exons?
Introns = non-coding region Exons = coding region
What is splicing?
It refers to the excision of introns to form mature mRNA from pre-mRNA
What is “polyadenylation”?
A poly-A tail (adenine residues) is added onto the 3’ end of RNA via poly-A polymerase
What are microRNAs?
Small non-coding RNAs which destabilise and inhibit the translation of RNA
What is the start codon / amino acid?
AUG - Methionine
Define Open Reading Frame
Sequence from start codon to stop codon
What does the small and large subunit of the Ribosome bind to?
Small subunit: mRNA and tRNA
Large subunit: amino acids
The ribosome reads the coding sequence of mRNA in which direction?
5’ to 3’
How is tetracycline a translation inhibitor?
It blocks entry of tRNA into the ribosomal complex
How is Chloramphenicol is a translation inhibitor?
It blocks entry of new amino acids into the peptide chain
Give examples of three post-translational modifications
Glycosylation
Phosphorylation
Ubiquintylation
