User:Jordan Scott/Sandbox RNA polII: Difference between revisions

From Proteopedia
Jump to navigationJump to search
← Older editNewer edit →
No edit summary
No edit summary
Line 14: Line 14:


===History===
===History===
The Discovery and Isolation of RNA Polymerase by Jerard Hurwitz


RNA Polymerase was first discovered and isolated by Jerard Hurwitz in 1960. Prior to this, there was research in the synthesis of RNA. One enzyme known as polynucleotide phosphorylase was first isolated. It was initially thought to synthesize RNA but it was later discovered to degrade RNA. This spurred Hurwitz to search for RNAP using E.coli extracts. In 1960 he showed reproducible RNA synthesis using his extracts and DNA. He published his findings along with three other labs who had also independently worked with RNAP.
RNA Polymerase was first discovered and isolated by Jerard Hurwitz in 1960. Prior to this, there was research in the synthesis of RNA. One enzyme known as polynucleotide phosphorylase was first isolated. It was initially thought to synthesize RNA but it was later discovered to degrade RNA. This spurred Hurwitz to search for RNAP using E.coli extracts. In 1960 he showed reproducible RNA synthesis using his extracts and DNA. He published his findings along with three other labs who had also independently worked with RNAP.
Line 55: Line 54:


Source: https://www.pnas.org/content/94/1/151.
Source: https://www.pnas.org/content/94/1/151.
1. <scene name='86/862225/Tfiid/1'>TextToBeDisplayed</scene> is highly conserved among eukaryotes. It recognizes and binds the TATA region of DNA. This is facilitated by a subunit named the TATA-binding protein (TBP). This subunit binding also causes major deformations in the helix which may be important for further binding of the PIC units.  
1. <scene name='86/862225/Tfiid/5'>TFIID</scene> is highly conserved among eukaryotes. It recognizes and binds the TATA region of DNA. This is facilitated by a subunit named the TATA-binding protein (TBP). This subunit binding also causes major deformations in the helix which may be important for further binding of the PIC units.  


2. <scene name='82/824648/Tfiib/3'>TFIIB</scene> is the second to join the PIC. It is thought to be responsible for stabilizing the TBP/DNA complex and tethering the TFIID-DNA complex to RNAP I. It is also important in specifying the the TSS. In vitro studies have shown that accurate initiation can occur with only TFIID, TFIIB, and RNAP II suggesting that tese two subunits serve to position RNAP. . Mutagenesis studies also suggest that it works as a bridge between TFIID and pol II.
2. <scene name='86/862225/Tfiib/1'>TFIIB</scene> is the second to join the PIC. It is thought to be responsible for stabilizing the TBP/DNA complex and tethering the TFIID-DNA complex to RNAP I. It is also important in specifying the the TSS. In vitro studies have shown that accurate initiation can occur with only TFIID, TFIIB, and RNAP II suggesting that tese two subunits serve to position RNAP. . Mutagenesis studies also suggest that it works as a bridge between TFIID and pol II.


3. <scene name='82/824648/Tfiif/5'>TFIIF</scene> binds directly to RNAP II and forms a very stable complex. It then escorts RNAP II to the promoter TFIIF also increases specificity and efficiency of transcription. It also acts similairy to bacterial sigma factor by inhibiting and reversing RNAP II binding to nonpromoter sites. (F)
3. <scene name='86/862225/Tfiif/1'>TFIIF</scene> binds directly to RNAP II and forms a very stable complex. It then escorts RNAP II to the promoter TFIIF also increases specificity and efficiency of transcription. It also acts similarly to bacterial sigma factor by inhibiting and reversing RNAP II binding to nonpromoter sites. (F)


4. <scene name='82/824648/Tfiie/4'>TFIIE</scene> is required to begin transcription even though RNAP II is bound to DNA before TFIIE binds. Once bound it recruits the last TF,  TFIIH.  
4.<scene name='86/862225/Tfiie/3'>TFIIE</scene> is required to begin transcription even though RNAP II is bound to DNA before TFIIE binds. Once bound it recruits TFIIH.  


5.<scene name='82/824648/Tfiih/3'>TFIIH</scene> supports catalytic activity such as DNA ATPase, DNA helicase, and a kinase that phosphorylates the CTD of RPB1.(F) Some of its subunits are also components of DNA repair machinery. It is the last TF to bind and completes the <scene name='82/824648/Pic/3'>PIC</scene>.  
5.<scene name='86/862225/Tfiih/1'>TFIIH</scene> supports catalytic activity such as DNA ATPase, DNA helicase, and a kinase that phosphorylates the CTD of RPB1.(F) Some of its subunits are also components of DNA repair machinery. It is the last TF to bind and completes the <scene name='82/824648/Pic/3'>PIC</scene>.  


6.<scene name='82/824648/Tfiia/3'>TFIIA</scene> is a co-activator that helps regulate PIC assembly. It was initially thought to be essential for activity.  It serves as an enhancer and stabilizes the early complexes. It also neutralizes transcription repressors. The mechanism is unknown but it is thought to either increase TBP affinity for DNA or displace repressors. (f)
6.<scene name='82/824648/Tfiia/3'>TFIIA</scene> is a co-activator that helps regulate PIC assembly. It was initially thought to be essential for activity.  It serves as an enhancer and stabilizes the early complexes. It also neutralizes transcription repressors. The mechanism is unknown but it is thought to either increase TBP affinity for DNA or displace repressors. (f)
Retrieved from "https://proteopedia.org/User:Jordan_Scott/Sandbox_RNA_polII"