RESUMEN
Intrinsically disordered proteins (IDPs) are highly flexible and undergo disorder to order transition uponbinding. They are highly abundant in human proteomes and play critical roles in cell signaling and regulatoryprocesses. This review mainly focuses on the dynamics of disordered proteins including their conformationalheterogeneity, protein–protein interactions, and the phase transition of biomolecular condensates that arecentral to various biological functions. Besides, the role of RNA-mediated chaperones in protein folding andstability of IDPs were also discussed. Finally, we explored the dynamic binding interface of IDPs as noveltherapeutic targets and the effect of small molecules on their interactions.
RESUMEN
Genes of the Rel/Spo homolog (RSH) superfamily synthesize and/or hydrolyse the modified nucleotides pppGpp/ ppGpp (collectively referred to as (p)ppGpp) and are prevalent across diverse bacteria and in plant chloroplasts. Bacteria accumulate (p)ppGpp in response to nutrient deprivation (generically called the stringent response) and elicit appropriate adaptive responses mainly through the regulation of transcription. Although at different concentrations (p)ppGpp affect the expression of distinct set of genes, the two well-characterized responses are reduction in expression of the protein synthesis machinery and increase in the expression of genes coding for amino acid biosynthesis. In Escherichia coli, the cellular (p)ppGpp level inversely correlates with the growth rate and increasing its concentration decreases the steady state growth rate in a defined growth medium. Since change in growth rate must be accompanied by changes in cell cycle parameters set through the activities of the DNA replication and cell division apparatus, (p)ppGpp could coordinate protein synthesis (cell mass increase) with these processes. Here we review the role of (p)ppGpp in bacterial cell cycle regulation.