RPS6 (ribosomal protein S6) is a structural component of the 40S small ribosomal subunit that plays critical roles in protein synthesis regulation and cellular signaling 1. The protein undergoes phosphorylation on five evolutionarily conserved serine residues in response to various stimuli, which has been extensively studied for four decades 1. RPS6 phosphorylation occurs downstream of mTORC1 signaling and serves as a key indicator of mTORC1 activity 234. Beyond its structural role in ribosomes, RPS6 functions in selective mRNA translation control, influencing cell growth and proliferation 1. The protein can be post-translationally modified through ADP-ribosylation by PARP-16, which inhibits polysome assembly and maintains protein homeostasis in cancer cells by preventing toxic protein aggregation 5. RPS6 also serves as a marker for ribosome-associated processes, as demonstrated in studies using RPS6 antibodies for RNA-immunoprecipitation to identify ribosome-bound RNAs 6. The protein's phosphorylation status reflects nutritional states and stress responses, with decreased phosphorylation observed during amino acid starvation and mTOR pathway inhibition 78.