Search results
Results from the WOW.Com Content Network
RNA polymerase II (also called RNAP II and Pol II) is an enzyme found in eukaryotic cells. It catalyzes the transcription of DNA to synthesize precursors of mRNA and most snRNA and microRNA . [ 3 ] [ 4 ] In humans, RNAP II consists of seventeen protein molecules (gene products encoded by POLR2A-L, where the proteins synthesized from POLR2C ...
RNA polymerase II holoenzyme is a form of eukaryotic RNA polymerase II that is recruited to the promoters of protein-coding genes in living cells. [11] It consists of RNA polymerase II, a subset of general transcription factors , and regulatory proteins known as SRB proteins.
In most prokaryotes, a single RNA polymerase species transcribes all types of RNA. RNA polymerase "core" from E. coli consists of five subunits: two alpha (α) subunits of 36 kDa, a beta (β) subunit of 150 kDa, a beta prime subunit (β′) of 155 kDa, and a small omega (ω) subunit. A sigma (σ) factor binds to the core, forming the holoenzyme.
DNA unwinding element proteins (DUE-Bs) are found in eukaryotes. [3] They act to initiate strand separation by binding to DUE. [3] DUE-B sequence homologs found among a variety of animal species- fish, amphibians, and rodents. [3] DUE-B's have disordered C-terminal domains that bind to the DUE by recognition of this C-terminus. [3]
Eukaryotic RdRp becomes active in the presence of dsRNA, and is less widely distributed than other RNAi components as it lost in some animals, though still found in C. elegans, P. tetraurelia, [37] and plants. [38]
Additionally, these segments includes regulatory sections, such as a promotor specific to the RNA polymerase I, as well as both transcribed and non-transcribed spacer segments. Due to their high importance in the assembly of ribosomes for protein biosynthesis , the rDNA genes are generally highly conserved in molecular evolution .
Vaults have been found to be highly expressed in "higher" eukaryotes, specifically mammals, amphibians, and avians, as well as "lower" eukaryotes, such as Dictyostelium discoideum. Given that both the structure and protein composition are highly conserved among these species, researchers posit that their function is crucial to eukaryotic cell ...
Proposed piRNA structure, with the 3′ end 2′-O-methylation. piRNAs have been identified in both vertebrates and invertebrates, and although biogenesis and modes of action do vary somewhat between species, a number of features are conserved. piRNAs have no clear secondary structure motifs, [1] [12] due to the fact that the length of a piRNA varies between species (from 21 to 31 nucleotides ...