Furthermore, it was shown that p70S6K, a crucial substrate of mTOR, and MEK play different roles in geroconversion [ 21].
In analogy to ubiquitin E2-like variants of the ubiquitin/proteasome pathways that lack active site cysteine residues and form heterodimers with E2 enzymes (VanDemark et al., 2001), SERAser, while catalytically inactive on their own, could act in concert with canonical SERAcys proteases and provide crucial substrate binding sites.
To confirm the identity of the catalytic residues, activity data using catalytically compromised active-site mutants are included in our analysis, i.e., variants where the acid/base catalyst (Glu166) and the nucleophile (Glu354), as well as a crucial substrate-binding side chain (Glu408) have been replaced by isosteric glutamine side chains.
In further research, more effort should be given to deciphering the signals and molecular mechanisms of TaSnRK2.8 in carbohydrate metabolism, especially in regard to crucial downstream substrates.
P70S6K and 4E-BP1 are two crucial downstream substrates of mTOR signaling.
Within the MCC, Mad2, Bub3 and BubR1 form a complex with Cdc20, an APC/C co-activator required for targeting crucial APC/C substrates at the metaphase anaphase transition.
Appropriate screening and further processing of information is dependent on an efficient balance with these core and automatic levels of processing; this process typically occurs outside of awareness with flexibility in crucial neural substrates that allows for conscious and near-conscious allocation of resources and responses toward potentially salient information.
Using a structural model, we were able to identify a glutamate residue (Glu324) that is crucial for substrate binding, and we could alter the substrate specificity by protein engineering.
This is known as the substrate-binding cleft, and residues in this region have been shown crucial to substrate binding and regulatory protein-protein interactions [23], [24], [25], [26], [27], [28], [29].
