More Gene Expression, Endomembrane system and trafficking

Question 1

enhancer DNA

Answer 1

transcription factors that stimulate transcription by binding

Question 2

silencer DNA

Answer 2

transcription factors that repress transcription by binding

Question 3

chromatin remodeling

Answer 3

changing transcription less directly; changing the wrapping of DNA by histone proteins

Question 4

histone

Answer 4

proteins that are attracted to each other and therefore can tightly bind the DNA; can add acetyl groups to cause more trasncription

Question 5

DNA methylation

Answer 5

adding a methyl side group to bases in DNA which causes DNA silencing and is temporary; recruits histone deacetylases which changes the transcription factor binding

Question 6

epigenetic changes

Answer 6

changes in transcription; can last for many cell divisions as the diluted histone and methylation modifications trigger local additions of histones/methylation

Question 7

microRNA

Answer 7

makes microRNA complementary to part of the mRNA which then blocks translation or triggers mRNA destruction

Question 8

trafficking

Answer 8

getting mRNA and proteins to the right place

Question 9

protein signal sequence

Answer 9

part of the protein chain and is seen as a “flag” which binds lock and key to a specific structure and carrier protein which traffic the protein

Question 10

nucleosome

Answer 10

a length of DNA coiled around a histone

Question 11

nuclear envelope

Answer 11

has 2 membranes which are perforated by nuclear pores

Question 12

nuclear localization signal sequence

Answer 12

sequence of amino acids which binds importin protein and the signal induces lock and key fit

Question 13

pore complex

Answer 13

collection of proteins outside of nucleus, conveyer belt