Given that the core enzyme tends to DNA in the cell, because of the electrostatic force. Why is there no such tendency between RNApolymerase 2 and RNA?
Pol II can actually bind and process RNA, cf. Article RNA polymerase II acts as an RNA‐dependent RNA polymerase to...
Hi Fateme ... In all species, transcription begins with the binding of the RNA polymerase complex (or holoenzyme) to a special DNA sequence at the beginning of the gene known as the promoter. Activation of the RNA polymerase complex enables transcription initiation, and this is followed by elongation of the transcript.
RNA polymerase in eukaryotic cells does not attach directly to promoters. Instead, helper proteins called basal (general) transcription factors bind to the promoter first, helping the RNA polymerase in the eukaryotic cells get a foothold on the DNA.
hi kakali thankyou for yor answer
but I want to know why the core enzyme does not bind to RNA?Although RNA is also acidic.
RNA polymerase core enzyme binds with sigma factor to form a holoenzyme and then locates a sequence specific promoter in the DNA strands (It will not bind to RNA because that sequence specific promoter is absent). Basically in bacteria like E. coli, the promoters are characterized by two hexameric DNA sequences, the -35 sequence and the -10 sequence named for their approximate location. In these promoters the frequencies of the four nucleotides (G,A, C,T) varies.
So after binding with the DNA strand the transcription begins. However once RNA polymerase has managed to synthesize about 10 nucleotides of RNA, sigma factor relaxes its grip.
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