In past researches, cryo-electron microscopy analysis has revealed the architecture of the substrate-free proteasome holoenzyme
in six distinct states.
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].
Our data support a model whereby [T.sup.287] autophosphorylation regulates substrate gating, an intrinsic property of the catalytic domain, which is amplified within the multivalent architecture of the CaMKII holoenzyme
Scott, "cAMP prevents glucose-mediated modifications of histone H3 and recruitment of the RNA polymerase II holoenzyme
to the L-PK gene promoter," Journal of Molecular Biology, vol.
They are the largest and third largest subunits of the holoenzyme
Kim et al., "Realizing the allosteric potential of the tetrameric protein kinase A RI[alpha] holoenzyme
," Structure, vol.
Xu, "Crystal structure of a protein phosphatase 2A heterotrimeric holoenzyme
," Nature, vol.
Tryptophan 2,3-dioxygenase activity was determined in rat liver homogenates (2gm of perfused frozen liver tissue in 13ml of 0.14M KCl (pH 7.0) was homogenized at 0C using Polytron homogenizer spinning at 13000 rpm for 2-3 minutes), either in absence (holoenzyme
activity) or in the presence (total enzyme activity) of added haematin 2M (haematin dissolved in 0.1M NaOH) as previously described in detail .
 Further biochemical analysis of the R964C holoenzyme
showed a 33% decrease in dTTP incorporation efficiency and a threefold decreased discrimination for d4TTP compared with the wild-type POLG1.
The homoplasmic15bp deletion results in abolishing the activity of COXI, COXII and COXIII subunits in holoenzyme
as all the subunits are related and dependent on the COXIII subunit.
It also interacts with the [[sigma].sup.54] RNA polymerase holoenzyme
Eukaryotes mainly use class la RRs, which comprise an [alpha]2/[beta]2 complex made up of two subunits a (termed R1) and [beta] (termed R2) that conglomerate to build the holoenzyme
with the active form supposed to adopt [alpha]2[beta]2 quaternary state (Aye et al.