RESUMEN
KRAS inhibitor AMG510 covalently modifies the G12C residue and inactivates the KRAS/G12C function. Because there are many reactive cysteines in the proteome, it is important to characterize AMG510 on-target modification and off-targets. Here, we presented a streamlined workflow to measure abundant AMG510 modified peptides including that of KRAS/G12C by direct profiling, and a pan-AMG510 antibody peptide IP workflow to profile less abundant AMG510 off-targets. We identified over 300 off-target sites with three distinct kinetic patterns, expanding the AMG510 modified proteome involved in the nucleocytoplasmic transport, response to oxidative stress, adaptive immune system, and glycolysis. We found that AMG510 covalently modified cys339 of ALDOA and inhibited its enzyme activity. Moreover, AMG510 modified KEAP1 cys288 and induced NRF2 accumulation in the nuclear of NSCLC cells independent of KRAS/G12C mutation. Our study provides a comprehensive resource of protein off-targets of AMG510 and elucidates potential toxicological sideeffects for this covalent KRASG12C inhibitor.
RESUMEN
In this work, a multiphase microstructure consisting of nanobainte, martensite, undissolved spherical carbide, and retained blocky austenite has been prepared in an Al-alloyed high carbon steel. The effect of the amount of nanobainite on the dry sliding wear behavior of the steel is studied using a pin-on-disc tester with loads ranging from 25-75 N. The results show that, there is no significant differences in specific wear rate (SWR) for samples with various amounts of nanobainite when the normal load is 25 N. While, the SWR firstly decreases and then increases with increasing the amount of nanobainite, and the optimum wear resistance is obtained for samples with 60 vol.% nanobainite, when the applied load increases to 50 and 75 N. The improved wear resistance is attributed to the peak hardness increment resulted from the transformation of retained austenite to martensite, work hardening, along with amorphization and nanocrystallization of the worn surface. In addition, the highest toughness of the samples with 60 vol.% nanobainite is also proven to play a positive role in resisting sliding wear. EDS (energy dispersion spectrum) and XRD (X-ray diffraction) examinations reveal that the predominant failure mechanism is oxidative wear.
RESUMEN
Photosystem I (PSI)-light-harvesting complex I (LHCI) super-complex and its sub-complexes PSI core and LHCI, were purified from a unicellular red alga Cyanidioschyzon merolae and characterized. PSI-LHCI of C. merolae existed as a monomer with a molecular mass of 580 kDa. Mass spectrometry analysis identified 11 subunits (PsaA, B, C, D, E, F, I, J, K, L, O) in the core complex and three LHCI subunits, CMQ142C, CMN234C, and CMN235C in LHCI, indicating that at least three Lhcr subunits associate with the red algal PSI core. PsaG was not found in the red algae PSI-LHCI, and we suggest that the position corresponding to Lhca1 in higher plant PSI-LHCI is empty in the red algal PSI-LHCI. The PSI-LHCI complex was separated into two bands on native PAGE, suggesting that two different complexes may be present with slightly different protein compositions probably with respective to the numbers of Lhcr subunits. Based on the results obtained, a structural model was proposed for the red algal PSI-LHCI. Furthermore, pigment analysis revealed that the C. merolae PSI-LHCI contained a large amount of zeaxanthin, which is mainly associated with the LHCI complex whereas little zeaxanthin was found in the PSI core. This indicates a unique feature of the carotenoid composition of the Lhcr proteins and may suggest an important role of Zea in the light-harvesting and photoprotection of the red algal PSI-LHCI complex.