Methylation Of Ribosomal Protein S10 Affects Its Interaction With B23

Ribosomes are responsible for the synthesis of polypeptide chains and its biogenesis is thus a critical process inextricably linked to cell growth and proliferation. Post-translational modifications of ribosomal proteins,including phosphorylation, methylation and acetylation,affect the ribosome biogenesis or activity.Protein arginine methyltransferases(PRMTs) are enzymes that catalyze the transfer of a methyl group from S-adenosylmethionine(SAM) to arginine.Protein Arginine Methyltransferase 5(PRMT5) is a member of PRMTs family.PRMT5 regulates other proteins' function through methylation a subset of substrates.In our previous experiments,57%Ribosomal Protein S10(RPS10) localizes in the granular component region(GC) in nucleus and the rest concentrates in dense fibrillar component region(DFC).However,RPS10 methylation mutant R158/160K solely concentrates in DFC region.The major results were as follows:â… .We found PRMT5 catalyzes RPS10 methylation at Arg158 and Argl60 residues.â…¡.Using co-immunoprecipitation we found RPS10 is a novel B23 binding protein,and this binding is proved to be direct through GST-pull down.Moreover,RPS10 methylation mutant interacts weakly with B23.And B23 is the mark protein of Granular component region in nucleus,and plays a vital role in ribosome biogenesis.So,we can say that B23 may bind to RPS10 methylated and store it in the GC region in nucleus.Together,we deduce that PRMT5 may play the multiple functions through methylating RPS 10 and affect its interaction with B23.