Gene structure Flashcards
-Name and explain the various components of a eukaryotic gene
What are the main components of a gene
-Insulator
-Enhancer/silencer
-promoter
-TATA box
-Transcription start site
-Kozak sequence
-Untranslated region
-Translatopn start site
-Intron
-Exon
-Translation stop site
-Transcription stop site
-Poly A signal
-Terminator
-Insulator
What is the funtion of an Insulator
-It is where the chromatin starts to unravel to form beads on a string structure.
-It also tells where to stop unraveling and become a chromatin structure again
What is the funtion of an Enhancer/silencer
E-inreases gene expression
S-Decrease gene expression
What is the funtion of a Promoter?
It contains binding sites for many transcription factors to bind to
What is the funtion of a TATA box
-It is rich in T’s and A’s
-A key transcription (TF2D) binds to it and recruits RNA Pol II in order to transcribe gene.
What is the funtion of a Transcription start site
RNA Pol II starts producing RNA strand
What is the funtion of a Kozak sequence
-This is where a ribisome binds to gene to start transcription
-Look for kozak sequence to find coding sequence
What is the funtion of an Intron
-Regulate gene expression and how much transcript is made (10 000 bases)
-Introns make Eu genes more complex as the same gene can be transcribed in many different orders to produce a variety of proteins.
Pro dont have introns
What is the funtion of an Exon
-Gene that codes for a protein
-The exon sequences are much smaller than Intron sequence
What is the funtion of a Transcription stop site
-RNA Pol II unbinds
What is the funtion of an untranslated region (UTR)?
UTR’s allow mRNA to form into a circular structure to allow translation to occur
They enable this by allowing the ends to associate with each other
What is the function of a Poly A signal sequence?
-It tells where a Poly A tail must e placed on the mRNA
