Additionally, the proximity of the 40S subunit to the helical junction IIIabc of domain III might be the cause of the concentration of substitutions in this IRES region, a region that has an important role during the formation of the 48S preinitiation
complex and during the recruitment of the 43S subunit and eIF3 .
In holoenzyme and preinitiation
complex (PIC) models based on refined EM and X-ray structures, both the middle and head modules make multiple contacts with diverse parts of Pol II and GTFs, explaining the molecular mechanism of Mediator-stimulated CTD phosphorylation by TFIIH and resultant enhancement of basal transcription [15, 16, 19].
VP64 in dCas9-VP64 complex recruits multiple components of a preinitiation
complex which when combined with gRNA targeting sequences near the promoter robustly activates gene expression  (Figure 8(a)).
Transcription factors can be categorized into general transcription factors and gene-specific transcription factors; general transcription factors are functional in creating the preinitiation
complex which, upon binding to DNA promoter regions, regulates basal transcription , whereas the binding of gene-specific transcription factors to genes is sequence-specific and promotes diverse gene expression .
Eventually, these events favor the recruitment of the p300 histone acetyltransferase and RNA polymerase II (RNAPII) preinitiation
complexes in the promoter region of Cox2 to promote COX-2 transcription.
The most characteristic cis-regulatory element, detected in the mGH, is the TATA box (Goldberg-Hogness box), a binding site of the TATA-Binding Protein (TBP) that is part of the transcription preinitiation
complex (Schluesche et al., 2008).
This particular protein is required for the formation of the preinitiation
Blenis, "mTOR and S6K1 mediate assembly of the translation preinitiation
complex through dynamic protein interchange and ordered phosphorylation events," Cell, vol.
All authors who address this issue agree that the engagement periods, whatever they are called, are distributed exponentially consistent with that they are terminated by the dissociation of transcription preinitiation
complexes of transcription factors from gene promoters.
Pharmacological inhibition of Top II in human cells is found to decrease Pol I transcription and Top IIa depletion both impairs Pol I preinitiation
complex (PIC) formation and produces a loss of DSBs at these sites.
The eIF1, eIF3, eIF5, and eIF5B associate followed by the formation of the 43S preinitiation
Yamamoto et al., "Eukaryotic translation initiation factor 5 is critical for integrity of the scanning preinitiation
complex and accurate control of GCN4 translation," Molecular and Cellular Biology, vol.