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Flashcards in Gene regulation Deck (31)
1

inducer

small effector molecule that causes transcription to increase in inducible genes

2

repressible genes

genes affected by corepressors binding to repressor proteins and inhibitors binding to activator proteins and blocking them from DNA

3

operon

a group of two or more genes under the transcriptional control of a single promoter

4

polycistronic mRNA

contains the coding sequence for two or more structural genes

5

operator

sequence of bases that provides a binding site for a repressor protein

6

bacteria attenuation

a sequence is added to the DNA and mRNA is stopped so that the protein being made is not completed

7

catabolic enzymes

enzymes used to break down macromolecules are usually inducible operons turned on by the substance

8

anabolic enzymes

enzymes used to produce macromolecules are usually repressor operons turned off by the product

9

allosteric enzyme

enzyme that contains two different binding sites with a regulatory and catalytic site

10

bacteriophage

viruses that infect bacteria

11

lysogenic phage

acting as temperate phage that integrates its genetic material into bacterial chromosome

12

lytic phage

increases the copies of the virus and lyses that bacteria

13

prophage

the integrated phage DNA into bacteria chromosome

14

general transcription factors

required for the binding of RNA polymerase to the core promoter

15

homodimer

two identical transcription factor proteins or other molecules that come together

16

heterodimer

two different transcription factor proteins or other molecules that come together

17

bidirectional regulatory element

can bind to DNA in the forward or reverse direction

18

transcription factor

proteins that influence the ability of RNA polymerase to transcribe a given gene

19

control elements

DNA sequence located near the core promoter; acted on by regulatory transcription factors; enhancer-silencer sequence

20

transcriptional activators

recruit chromatin remodeling enzymes: ATP dependent chromatin remodeling/histone modification by histone acetyltransferase

21

CpG islands

unmethylated islands are located near promoters of active genes and methylated are near suppressed genes

22

housekeeping genes

encode proteins required and expressed in most cells of multicellular organisms

23

alternative splicing

some pre-mRNAs can have exons spliced to produce dozens of different mRNAs

24

constitutive exons

encode polypeptide segments of acertain protein necessary for general structure

25

alternative exons

encode polypeptide segments of a certain protein that change the function for specific cells

26

splicing factors

exon modulation by repressing or enhancing a specific exons

27

poly A binding protein

binds to the poly A tail; the poly A tail is lossed and exonucleases digest without a binding protein

28

3' untranslated region

located between the stop codon and the polyA tail

29

AU rich element

ARE; this is a destabalizing element which attracts proteins the rapidly degrades the mRNA

30

pre-miRNA

forms a hairpin structure that is cut by the endonuclease dicer forming double stranded RNA

31

RISC

RNA-induced silencing complex; one of the RNA strands combines with RISC and will degrade the complimentary mRNA strand