Unit 8 - Control of Gene Expression Flashcards
Mutation
Any change to one or more nucleotide bases or any rearrangement of bases in DNA.
Occur spontaneously due to external mutagens.
Types of mutation that can occur
Addition, deletion, substitution, inversion, duplication and translocation.
Types of mutation (overall effect on DNA)
Silent
Termination
Frameshift
Transcription factor
Protein molecule that binds to a promoter and turns on gene expression.
Promoter
Short region of DNA upstream from a gene, which the transcription factor binds to.
Proteome
All the proteins produced by the genome
Genome
All the genetic material in an organism
Recombinant DNA technology
Involves the transfer of fragments of DNA from one organism (or species) to another.
Palindrome
Two sequences being opposite to one another
Transformation
The reintroduction of the new plasmid into bacterial cells.
Involves mixing plasmids and bacterial cells together in a Ca2+ rich medium.
Vector
Transfers genes from one organisms into another
Gene marker
Way of identifying which cells have taken up the plasmid with the desired gene
Primers
Short nucleotide sequences that have a set of bases complementary to those at one end of each of the two DNA fragments
Translocation of bases
A portion of DNA becomes separated and reinserted itself into another chromosome
Mutagenic agents
High energy ionising radiation, chemicals and other things may cause mutations within DNA
Totipotency
Can differentiate into any type of cell
Pluripotency
Can differentiate into almost any type of cell
Multipotency
Can differentiate into a limited number of cells
Unipotency
Can differentiate into only one type of cell
Oestrogen
A hormone which activates transcription when it isn’t meant to occur.
Bonds to receptor that changes transcription factors shape.
Epigenetics
Looks at how the environment affects the expression of genes within organisms
Acetylation
Attachment of acetyl tags to the histones which unwind and become more loosely associated with the DNA leading to the switching on of genes
Methylation
Attachment of methyl tags to be cytosine bases leading to a stronger association between histones and DNA leading to the switching off of genes.
Oncogenes
Mutated version of proto-oncogene. Leads to uncontrolled cell division
Tumour suppressor genes
Gene in charge of suppressing rumour growth in cells
Restriction endonuclease
Enzyme used to chop up DNA leaving either blunt or sticky ends
Reverse transcriptase
Enzyme used to make DNA from RNA strands. Important in development of insulin producing DNA from DNA templates
Palindrome
When sticky ends are produced, the same enzyme is used creating complimentary ends known as a palindrome
Vector
Thing in which DNA is transported into a cell having been developed
Promoter
Portion of genetic material upstream of a coding sequence to which the transcriptional factor attaches
RISC
Enzyme guided by siRNA strand to the target mRNA and cuts it into smaller pieces
DICER
Initially cuts up double stranded RNA into siRNA
siRNA
Small portions of mRNA that guide the RISC enzyme to its complimentary portion of target mRNA
Marker genes
Genes used to highlight whether an artificially inserted gene has been successfully incorporated into a genome of an organism
Polymerase chain reaction
Process by which DNA can be copied in a machine using varying temperatures
DNA hybridisation
When DNA or DNA is heated hip causing separation of strands which when cooled will join with whichever complimentary base sequence they contact first
Genetic screening
Ability to search within an organisms DNA for a specific allele
Gel electrophoresis
Technique used to split up DNA fragments for analysis and comparison to other DNA samples
Genetic counselling
Where advice and information is given to couples in order to make informed decisions about their offspring
Vntrs
Variable number tandem repeats are portion of non coding bases of DNA. 95% of the human genome is introns
