Most neurodegenerative diseases such as Alzheimer’s disease, type 2 diabetes, Parkinson’s disease, etc. are caused by inclusions and plaques containing misfolded protein aggregates. These protein aggregates are essentially formed by the interactions of either the same (homologous) or different (heterologous) sequences. Several experimental pieces of evidence have revealed the presence of cross-seeding in amyloid proteins, which results in a multicomponent assembly; however, the molecular and structural details remain less explored. Here, we discuss the amyloid proteins and the cross-seeding phenomena in detail. Data suggest that targeting the common epitope of the interacting amyloid proteins may be a better therapeutic option than targeting only one species. We also examine the dual inhibitors that target the amyloid proteins participating in the cross-seeding events. The future scopes and major challenges in understanding the mechanism and developing therapeutics are also considered. Detailed knowledge of the amyloid cross-seeding will stimulate further research in the practical aspects and better designing anti-amyloid therapeutics.
The use of remdesivir to treat COVID-19 will likely continue before clinical trials are completed. Due to the lengthening pandemic and evolving nature of the virus, predicting potential residues prone to mutation is crucial for the management of remdesivir resistance. Using a rational ligand-based interface design complemented with mutational mapping, we generated a total of 100,000 mutations and provided insight into the functional outcomes of mutations in the remdesivir-binding site in nsp12 subunit of RdRp. After designing 46 residues in the remdesivir-binding site of nsp12, the designs retained 97%–98% sequence identity, suggesting that very few mutations in nsp12 are required for SARS-CoV-2 to attain remdesivir resistance. Several mutants displayed decreased binding affinity to remdesivir, suggesting drug resistance. These hotspot residues had a higher probability of undergoing selective mutation and thus conferring remdesivir resistance. Identifying the potential residues prone to mutation improves our understanding of SARS-CoV-2 drug resistance and COVID-19 pathogenesis.
Leishmaniasis caused by obligate intracellular parasites of genus Leishmania is one of the most neglected tropical diseases threatening 350 million people worldwide. Protein kinases have drawn much attention as potential drug targets due to their important role in various cellular processes. In Leishmania sp. mitogen-activated protein kinase 4 is essential for the parasite survival because of its involvement in various regulatory, apoptotic and developmental pathways. The current study reveals the identification of natural inhibitors of L. donovani mitogen-activated protein kinase-4 (LdMPK4). We have performed in silico docking of 110 natural inhibitors of Leishmania parasite that have been reported earlier and identified two compounds Genistein (GEN) and Chrysin (CHY). The homology model of LdMPK4 was developed, followed by binding affinity studies, and pharmacokinetic properties of the inhibitors were calculated by maintaining ATP as a standard molecule. The modelled structure was deposited in the protein model database with PMDB ID: PM0080988. Molecular dynamic simulation of the enzyme-inhibitor complex along with the free energy calculations over 50 ns showed that GEN and CHY are more stable in their binding. These two molecules, GEN and CHY, can be considered as lead molecules for targeting LdMPK4 enzyme and could emerge as potential LdMPK4 inhibitors.
4 January 2022 in Biochimica et Biophysica Acta (BBA) - Molecular Cell Research