Thus, we confirmed our previous data that explain the role of residue at position 209 in PKA I[alpha] function .
In both cases, N3A-motif is displaced from the PBC, and its position is in good agreement with the structure of PKA I[alpha] A-domain in B-conformation .
It is so because this motif in H-conformation and B-conformation and C-helices in B-conformation occupy the same segment of space in PKA cAMP-binding domains.
The strength of an acid is determined by the particular acid's pKa
A ativacao da enzima adenilato ciclase promove aumento na concentracao intracelular de cAMP, que interage e regula outras proteinas, como a proteina quinase A (PKA) tambem designada proteina quinase A dependente de cAMP (34).
De acordo com Fan e Sun (16), a ativacao e inativacao da MAPK tambem esta relacionada a variacao na concentracao de cAMP e PKA, tanto no oocito quanto nas celulas do cumulus.
Sob baixa concentracao intraoocitaria de cAMP e consequentemente de PKA, ocorre a ativacao do MPF que promove a fosforilacao das proteinas do envoltorio nuclear, dissolucao do nucleolo, condensacao cromossomica e reorganizacao do citoesqueleto, ou seja, ocorre a GVBD e progressao da meiose ate MII (47).
The pH was controlled by adding a citrate-phosphate buffer system (see Table 3) in order to conduct the second-stage polymerizations in the pH range of 3-7, spanning the pKas of the MAA seed terpolymers.
These data are plotted in Figure 7 and from them we have determined that the pKa of this copolymer is close to 6, and not very sensitive to temperature in the range of interest.
As we now move to pH levels above the pKa of the MAA terpolymer (ca.
intraoocytic PKA inhibits GVBD in mammals, whereas the relief of PKA's effects in response to decreased cAMP levels promotes GVBD (Kovo et al., 2006; Zhang et al., 2008; Pirino et al., 2009; Oh et al., 2010).
However, a solitary GVBD-promoting cascade is difficult to reconcile with the fact that some of the drugs exhibiting differential effects on SW versus cAMP-induced GVBD alter targets downstream to cAMP such as PKA, the PKA substrate Cdc25, or even MPF itself (Fig.