32 RNAmRNAtRNArRNAmRNAmRNAE.coli RNA2DNA

mRNADNAmRNADNARNAmRNAmRNA

D. S. DNA DNARNA DNA3 5, DNARNA5 3.DNA(DNA)3----TACTCAT----5RNA 5----AUGAGUA----35---ATGAGTA----3Non-template (sense strand)template (antisense strand)

DNA RNApromotion, elongation, termination promoterterminator transcriptional unit polycistron in operon +1 monocistron, No operon

mRNA

RNA RNA5335 DNA DNA

DNADNADNARNA

DRNARNA-RNA

RNA (transcription)DNADNARNA

553355DNARNADNA(DNA

RNADNARNARNARNA RNA

RNADNA3'5'RNA5'3'

RNADNADNA

RNA ATPGTPCTPUTP DNA

RNADNARNADNA5'3'RNA

RNA2' 2'RNA

' DNA

RNARifampinRNA

RNA-1012

-

RNA pol rRNA

RNA pol HnRNA

RNA pol tRNA

snRNA5S rRNA

RNA

150kdRNARNA 2nusA69kdRNARNA

NusA protein ; 69 Kd, acid protein RNApol-attaching factor Impel RNApol. pausing in terminator for 1-15 and waiting for Rho factor to stop transcription of RNA (antitermination N protein utilization substance)

CAPcAMPCRP23kdcAMPRNA

RNA RNA -35TTGACA RNA-10TATAATPribnow DNA

RNADNApromoter) pppGpppA

Core promoter region including -35 (R)-10 (B)+1 (I)RNA

l Sextama Box Pribnow Box 17bp, RNApoll Sextama Box or Pribnow Box mut. 17 bpup mutation17 bpdown mutation17bp17bpSextama Box and Pribnow Box mut. 100X 1000X

(Re-usable) Holo-enzymeSextama Box, RNApol DNA107/mol R, B site (1014/mol)RNA

Promoterfactor strong promoter & weak promoter -35-10 ( ) -35, -10 RNApol factor is responsible for recognition of consensus sequence of promoter and only required for initiation.

TAHognessTATA CAATGC

Promoter for basic transcription ( class II recognized by RNA polymerase II ) l Cap site ; initiation point (+1) Capping m7GpppA/G------70 ---AUG---(in mRNA)

Promoter for basic transcription l TATA box / Hogness box / Goldberg-Hogness box (-30) Rich AT and rich GC flanked rich GC------T A T A A (T) A A (T)------rich GC 82 97 93 85 63 (37) 83 50 (37)

Promoter for basic transcription l GC island (C no methylated) and CAAT box (CAT box UPE) (-70) GCGC-----GGC(T)CAATCT---- Response to effect of transcription Range 30 bp

l Promoter functions CAAT box (modulator) controlling transcriptional efficiency (cause GC island) TATA box (selector) controlling starting point and efficiency I site (initiator)determination initiation point and capping of mRNA

RNAtrans-criptional factor, TF) TFATFBTFDTFETFFTF-I

Cis-factor for inducible expression HSE ( Heat Shock Element )GRE ( Glucocoricoid Response Element ) MRE ( Metal Response Element )TSE ( Tissue Special Element )l Inducible expressed by environment Ig ATGGAAAT + Oct-2 factor B GH ATGAATAT + Pit-1 factor

l EnhancerEnhance expression Basic expressionPosition not be fixed isolated region Bi-directional element Mono-directional element EnhancerPromoterChambon discovered the first enhancer inthe 5'-flanking region of the SV40 early gene.

Enhancer ----Enhancer (Enhancer Element) ----Enhancer Element , (Enhanson ----Enhanson(cis-factor)(trans-factor)

e.g. SV40 Enhancer (-179~ -250)

Silencer Mating type (MAT) of yeast

Silencer can act at a distance (at least 1 kb away) to modulate transcription somehow cause the chromatin to coil up into a condensed Inaccessible Inactive form thereby preventing transcription of neighboring genes

TFA TFD TFB pol TFD TATA TFE ATPase TFF RNA

trans-factor Trans-factor for basic transcription l TF (I, II, III) Transcriptional Factorl TBP (TATA box Binding Protein)l TAF (TBP Associate Factor)l RAP (RNApol. Associate protein)RNApol

RNApol II (B); ---For pre-mRNA transcription ---Located in nucleoplasm ---L maximum subunit 240 kd & have specific COOH-end named CTD ( Carboxyl Terminal Domain ) only in RNApol II ---CTD-end; 7aa repeats & high frequency phosphorylation TyrSerPProThrPSerPProSerP

Yeast 26XDrosophila 44X repeat unit of 7 aa / in CTDRat & Human 52X ---CTDSer,Thr L 3Subforms IIO (240kd) IIA (220kd) IIB (180kd) CTD over-phosphorylated 10X IIA Non-physiological form Initially binds to promoter

(TBP); needed for RNApol I, II, III Very high conserved C-end domain of 180 aa Binds with DNA in minor groove & wilds it Determination initiation starting site Control UPE effect for basic transcriptionTFIID; A sort of protein complex (TBP & > 8 TAF)

Promoter clearance Transcription startingF

Wilds minor groove pre-TIC Basic TIC conclusion

Promoter clearance Transcription startingcomplete TIC

Different acidic activation domain may regulation different cis-factor targets cis-factor positive control system

activator signalbinding DNA

lCys/Cys, Cys/His (Zinc finger)DNA-binding domainl Helix()-turn-Helix() (HTH) lHomeodomains (HDs 60aa with HTH)

9 direct repeats 30aa / copy

2Cys / 2His or 2Cys / 2Cys types

2Cys (2C) ~ Zn ~ 2His (2C) to form finger of 1-helix & 1-sheetZinc finger

Aaron Klug (1985)TFIIIA predict the Zinc finger structureTFIIIA three fingers lining up the major groove of DNA which sequence GCGTGGGCGCarl Pabo obtained the structure of complex between TFIIIA and DNA using X-ray crystallography

RNAATPGTP3',5'-

DNARNA

RNA1DNAGCATRNAURNARNA2()RNA

RNA mRNA 1(adding cap)mRNA5'-m7GTPHnRNA5'-GpppNG

RNAmRNAmRNARNA5 3polyA

RNASAMA3AAUAAARNA

2(adding tail)3'-polyApolyAmRNA

pre-RNA tailing A poly(A) tail (50-200) be added at -20 Nt tailing signal (AAUAAA) from 3-end of Pre-RNA

3splicing)HnRNAsnRNA

RNAG

4

tRNA

mRNA

tRNA

rRNA

rRNA

RNAUgRNARNARNAtRNAmRNA

Editing /AUG, UAA, UAG, UGA codon mRNA editing DNA DNA abbreviated cryptic gene, cryptogene

Editing