Regulatory RNA II

Question 1

Long noncoding RNAs (lncRNAs) basic definition:

Answer 1

200 nt - 100 kb, lacking ORF or short ORF

Question 2

lncRNAs features (2):

Answer 2

Nucleotide sequence not highly conserved, mRNA-like transcripts (transcribed by RNA polymerase II, 5’capping, polyA tail, epigenetic markers, introns)

Question 3

lncRNA expression (3):

Answer 3

1) Regulated 2) More tissue specific than proteins 3) Lower than protein expression

Question 4

lncRNA potential “sources” (4):

Answer 4

1) Transposable elements 2) Change of protein-coding gene into non-coding transcript 3) Chromosomal rearrangement 4) Duplication

Question 5

lncRNAs defined by ________ relative to _______

Answer 5

Location, protein-coding genes

Question 6

lincRNA

Answer 6

Long intergenic non-coding RNA, “stand-alone”

Question 7

Good indicator of lncRNA function

Answer 7

Subcellular localization

Question 8

Majority of lncRNAs localize to _______, some in ______

Answer 8

Nucleus, cytoplasm

Question 9

Functional traits of RNA (6):

Answer 9

1) Enhancer 2) Decoy 3) Guides 4) Scaffolds 5) Modifiers 6) ceRNA

Question 10

Enhancer role

Answer 10

Stimulate transcription of certain genes by recruitment

Question 11

Decoy role

Answer 11

Sequester proteins/RNAs to inhibit function

Question 12

Guide role

Answer 12

Recruit protein/RNAs to specific sequences/molecules, guide chromatin-modifying enzymes

Question 13

Scaffold role

Answer 13

Bridge sets of proteins/RNAs to sites, act as platform

Question 14

Modifier role

Answer 14

Allosterically (reg. of enzyme by binding at site other than active site) modifying proteins activity or RNA moelcules

Question 15

ceRNA role

Answer 15

competing endogenous RNA, containing miRNA target sites, titrate away mRNA from targets

Question 16

lncRNAs act in _____ to regulate local environment

Answer 16

cis

Question 17

lncRNAs act in _____ to regulate distant environment

Answer 17

trans

Question 18

lncRNAs in biological processes examples:

Answer 18

Xist, NEAT1, MALAT1, FIRRE, CDR1as

Question 19

Xist description:

Answer 19

Xist lncRNA is expressed to inactivate X chromosome, two active X chromosomes is lethal, Rep2 recruits Polycomb repressive complex 2 (PCR2) to upreg Xist

Question 20

lncRNAs in cancer

Answer 20

Differential expression, cancer-specific lncRNA patterns, potential development of them as biomarkers and therapeutic targets

Question 21

Discovery of lncRNAs

Answer 21

Genome and RNA sequencing, bioinformatic analysis and functional assays

Question 22

lncRNAs contribute to following developmental processes:

Answer 22

Epigenetic regulation, transcriptional and translational control, organization of nuclear architecture, regulation of other ncRNAs