Ribosomal proteins of HeLa cells.

Ribosomal proteins from HeLa cells were analyzed by two-dimensional polyacrylamide gel electrophoresis (Kaltschmidt-Wittmann) and dodecylsulfate polyacrylamide gel electrophoresis (Laemmli). 35 proteins are associated with the small ribosomal subunit and 47 proteins with the large ribosomal subunit. The HeLa ribosomal proteins S6, S32, L40b,c, L41 and L42 are phosphorylated in vivo and in vitro. Minor differences between HeLa and rat liver ribosomal proteins were revealed by their direct coelectrophoresis.