Gene expression Flashcards
3’ poly-A tail
A chain of adenine nucleotides added to the 3’ end of pre-mRNA during RNA processing. It makes the RNA molecule more stable and prevents its degradation.
5’ methyl-G cap
A molecule added to the 5’ end of pre-mRNA during RNA processing. It makes the RNA molecule more stable and prevents its degradation. It also helps the ribosome attach to the mRNA.
Activator protein
A protein coded for by a regulatory gene that increases gene expression.
Alternative splicing (gene expression)
The functional group on amino acid molecules that is made up of one nitrogen and two hydrogens (NH2)
Anticodon
Sequence of three nucleotides on a tRNA molecule that recognises a specific sequence of three nucleotides (codon) on an mRNA strand.
antiparallel - DNA
A characteristic of DNA strands describing
how each strand runs in an opposite direction to the other. One strand runs in a 3’ → 5’ direction and the other runs in a 5’ → 3’ direction.
Coding strand
The strand of DNA not transcribed by RNA polymerase, contains an identical sequence to the mRNA strand produced (except thymine is replaced with uracil in mRNA).
Codon
The sequence of three nucleotides in mRNA coding for one amino acid.
Degenerate
A property of the genetic code which means that a single amino acid can be coded for by more than one codon.
Exons
Regions of DNA that code for proteins and are not spliced out during RNA processing
Gene
A section of DNA that carries the code to make a specific protein or RNA product.
Gene expression
The process of reading the information stored within a gene to create a functional product, typically a protein.
Genetic code
The set of rules by which information is encoded in genetic material.
Genome
The complete set of DNA housed within an organism.
Introns
Non-coding regions of DNA that do not code for proteins. They are spliced out during RNA processing.