Search results
Results From The WOW.Com Content Network
In bacteria, termination of RNA transcription can be rho-dependent or rho-independent. The former relies on the rho factor, which destabilizes the DNA-RNA heteroduplex and causes RNA release. [22] The latter, also known as intrinsic termination, relies on a palindromic region of DNA. Transcribing the region causes the formation of a "hairpin ...
RNA polymerase, assisted by one or more general transcription factors, then unwinds approximately 14 base pairs of DNA to form an RNA polymerase-promoter open complex. In the open complex, the promoter DNA is partly unwound and single-stranded. The exposed, single-stranded DNA is referred to as the "transcription bubble". [6]
Function of RNA polymerase II (transcription). Green: newly synthesized RNA strand by enzyme. RNA polymerase II (RNAP II and Pol II) is a multiprotein complex that transcribes DNA into precursors of messenger RNA (mRNA) and most small nuclear RNA (snRNA) and microRNA. [1] [2] It is one of the three RNAP enzymes found in the nucleus of ...
A reverse transcriptase (RT) is an enzyme used to convert RNA genome to DNA, a process termed reverse transcription.Reverse transcriptases are used by viruses such as HIV, COVID-19, and hepatitis B to replicate their genomes, by retrotransposon mobile genetic elements to proliferate within the host genome, and by eukaryotic cells to extend the telomeres at the ends of their linear chromosomes.
This allows the RNA polymerase to bind to the mal promoter (#3). Transcription of malE, malF, and malG genes then proceeds (#4) as maltose activator protein and RNA polymerase moves down the DNA. [1] malE encodes for maltose-binding periplasmic protein and helps maltose transport across the cell membrane.
Transcription elongation is not a smooth ride along double stranded DNA, as RNA polymerase undergoes extensive co-transcriptional pausing during transcription elongation. [30] [31] In general, RNA polymerase II does not transcribe through a gene at a constant pace.
The preinitiation complex (PIC) is a large complex of proteins that is necessary for the transcription of protein-coding genes in eukaryotes and archaea.The PIC helps position RNA polymerase II over gene transcription start sites, denatures the DNA, and positions the DNA in the RNA polymerase II active site for transcription.
This is in contrast to typical DNA-dependent RNA polymerases, which all organisms use to catalyze the transcription of RNA from a DNA template. RdRp is an essential protein encoded in the genomes of most RNA-containing viruses that lack a DNA stage, [1] [2] including SARS-CoV-2.