Lecture 5 For Midterm Ii

Front 1

what is RNA processing

Back 1

pre-mRNA molecule undergoes three main modifications

Front 2

what are the three main modifications pre-mRNA molecules undergoes during RNA processing

Back 2

5' capping

3' polyadenylation

RNA splicing

Front 3

in eukaryotes, RNA is processed during ______________

Back 3

transcription

Front 4

what occurs during the addition of 5' cap

Back 4

7-methyl guanosine is added to 5’end of the transcript by RNA polymerase II

Front 5

1st step for the addition of the poly(A) tail (Polyadenylation_

Back 5

Termination sequence on DNA: AATAAA or ATTAAA

Front 6

second step for the addition of the poly(A) tail (Polyadenylation_

Back 6

Termination sequence is transcribed to RNA (AAUAAA or AUUAAA) by RNA polymerase II.

Front 7

3rd step for the addition of the poly(A) tail (Polyadenylation_

Back 7

Ribonuclease recognizes AAUAAA or AUUAAA and cleaves ~20 bp downstream

Front 8

fourth and last step for the addition of the poly(A) tail (Polyadenylation_

Back 8

Poly-A polymerase adds “A” at 3’end.

Front 9

purpose of RNA splicing is to

Back 9

remove introns

Front 10

what are exons

Back 10

coding region of a gene

Front 11

after processing the _____________ remain in mRNA

Back 11

exons

Front 12

what are introns?

Back 12

intervening sequence in a gene

Front 13

how are introns removed from RNA

Back 13

splicing

Front 14

what does the dystrophin gene do

Back 14

strengthens muscle fibers and protects from injury

Front 15

Duchenne muscular dystrophy (DMD) patients have RNA...

Back 15

processing error

Front 16

muscular dystrophy is due to a loss of ________

Back 16

exons

Front 17

muscular dystrophy is a ________________________- trair

Back 17

x-linked recessive

Front 18

what is a Lariat

Back 18

=intron folds back on itself, forming a structure called lariat

Front 19

1st step of RNA splicing consensus

Back 19

splice donor (5' splice site) G U

Front 20

2nd step of RNA splicing consensus

Back 20

3' splice site (splicing acceptor)

Front 21

3rd step of RNA splicing consensus

Back 21

branch site,

(A nucleotide is only critical one)

Front 22

fourth step of RNA splicing consensus

Back 22

distance between A and 3' splice site 18-40 nucleotides

Front 23

1st step of process splicing

Back 23

pre m-RNA is cut by spliceosome at G, U (5' splice site)

EXON 1 IS FREE

Front 24

2nd step of process splicing

Back 24

G at 5' splice site attaches to A at branch site and form lariat structure

Front 25

during the second step of splicing premRNA is cut by ______________ at __' splicing site(AG)

during the

Back 25

spliceosome

3'

Front 26

during the second step of splicing exon __ and exon __ are ______________

Back 26

1 and 2

ligated

Front 27

what happens to lariate site after splicing

Back 27

it is degraded

Front 28

what is transesterification

Back 28

exchange the organic groups between an ester and an alcohol

Front 29

the first transesterification has an ____ group and a branch site at A and an ___ group with a splice site at __' at __

Back 29

OH; A

Ester; 5' ; G

Front 30

the second transesterification has an ____ group and at _______ and an ___ group with a splice site at __' at __

Back 30

OH; exon 1

Ester; 3'; G

Front 31

the ______ group attacks the __________group

Back 31

OH

Ester

Front 32

spliceosome consists of these three things

Back 32

5 snRnPs

RnA

other proteins

Front 33

what are snRNPs

Back 33

small nuclear ribonucleoproteins

Front 34

the splicing mechanism's 1st step is

Back 34

splicing by splicesome

Front 35

the splicing mechanism's 2nd step is

Back 35

splicing by ribozyme

Front 36

the ______________ can form ribozyme

Back 36

intron

Front 37

the ribozyme has _____ only and no proteins

Back 37

RNA

Front 38

during self splicing, the _________ itself catalyzes its own ____________

Back 38

intron

removal

Front 39

what is alternative splicing

Back 39

Same pre-mRNA can be spliced in more than oneway to yield multiple mRNAs that are translated into different amino acidsequences and thus different proteins

Front 40

the mechanism for alternative splicing is through _______________________ proteins

Back 40

RNA binding proteins

Front 41

the splice activator is located on exons __, __, and __

Back 41

1

2

4

Front 42

splice activator binds right before exon __

Back 42

4

Front 43

the splice repressor binds right before the ____ exon and splices off _____ exons

Back 43

3rd

3-4

Front 44

Both _____________________ and _____________________ can exist in the same pre-mRNA transcript

Back 44

alternative splicing and multiple3’ cleavage sites

Front 45

70-90% of human genes undergo alternative splicing. what does this allow?

Back 45

for the production of different proteins from the same gene

Front 46

calcitonin gene has __ exons and __ introns

Back 46

6 exons

5 introns

Front 47

thyroid consists of pre-mRNA with exons _________________

Back 47

1-6

Front 48

in thyroid combinations..

__' cleavage occurs after __-exon and splicing

Back 48

3'

4th exon

Front 49

what exon forms mature mRNA

Back 49

exon 1-4

Front 50

thyroid calcitonin's function is to

Back 50

reduce concentration of calcium in the blood

Front 51

the brain consists of pre-mRNA with exons _____

Back 51

1-6

Front 52

in brain combinations

__' cleavage occurs after exon __

Back 52

3'

6

Front 53

for alternation splicing in brain combinations, exon -_ is removed

Back 53

4

Front 54

mature mRNA comes from exons ___

Back 54

1-6

Front 55

brain calcitonin function is to

Back 55

cause dilation of blood vessels

Front 56

what is trans-splicing?

Back 56

RNA processing in eukaryotes where exons from two different pre-mRNA are joined end-to-end and ligated

Front 57

trans-splicing is used by _______________ organisms

Back 57

microbial