Transcription of non-coding genes such as rRNA and tRNA uses RNA polymerase I, II, and III which each have their own transcription factors. RNA polymerase I requires the factors SL1 and UBF to initiate transcription of rRNA genes. The rRNA gene promoter contains core and upstream control elements. RNA polymerase III promoters come in various forms containing Box A, B, and C elements and recruit the transcription factors TFIIIC and TFIIIB to initiate transcription. Each RNA polymerase utilizes the TATA binding protein factor as part of their transcription initiation process for non-coding genes.

1. Transcription of non
coding genes
• Suraj. S. Mauryav
• R.k.Talreja College
• Msc – part ll
• 2227005
Gshaj

2. Transcription
•Transcription is
the process to
synthetics DNA to
RNA

3. Transcription in the non coding genes
• Enzyme works as with own unique setvof general
transcription factor.
• TBP ( TATA Binding protein) is the general transcription
factor.
• TBP is involved in initiating transcription by Pol – I and
Pol -II and as well as Pol –II.
• Pol –I required only one gene for expression that
encoding the rRNA precursor.

4. • The promotor for the rRNA
gene Comprises two Parts
• Core element
• UCF ( Upstream control
element)
• The former is located around
the start site of
transportation.

5. • Pol –l is required two other factors
this is SL1(Selective factor 1 ) , and
UBF (Upstream binding protein).
• SF-1 is the binds to the promotor
gene .
• Sl -1 made up of two factor TBP And
TAFs specific for Pol I transcription.
• This complex binds to the
downstream half of UCE (called site
A).
• SL1 binds DNA only in the presence of
UBF. That factor binds to the
upstream half of UCE called site B.

6. • Pol III promoters come in various forms, and the vast majority
havethe unusual feature of being located downstream of the
transcription start site.
• Some Pol III promoters consist of two regions, called Box A and Box
B, separated by a short element and others contain Box A and Box
C.still others contain a TATA element like those of Pol II.
• Pol II and Pol I, transcription by Pol III requires transcription
factors in addition to polymerase.
• This factors are called TFIIIB and TFIIIC (for the tRNA genes), and
those plus TFIIIA for the 5S rRNA gene.

7. • TFIIIC complex binds to the promoter region
and This complex recruits TFIIIB to the DNA.
• Just upstream of the start site, where it in turn
recruits Pol III to the start site of transcription.
• The enzyme then initiates, and displacing
TFIIIC from the DNA template as it goes.
• As with the other two
• classes of polymerase, Pol III uses TBP. In this
case, that ubiquitous
• factor is found within the TFIIIB complex.

8. •Thank you