ADP-ribosylation of heterogeneous ribonucleoproteins in HeLa cells.
Poly and mono (ADP-ribosyl)transferases catalyze the transfer of ADP-ribose from nicotinamide adenine dinucleotide (NAD) to acceptor proteins. Protein substrates of ADP-ribosylation reactions were investigated in human cervical carcinoma (HeLa) cells in the exponential phase of growth. Permeabilized cells were incubated with [32P]-NAD and ADP-ribosylated proteins were detected by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and autoradiography. Microsequencing of two coomassie blue-stained proteins corresponding to 32P-labeled proteins on autoradiographs revealed sequence identity with heterogeneous ribonucleoproteins (hnRNPs) A1 and A2/B1, consistent with the isoelectric points, molecular sizes, and 2D-PAGE map locations of these proteins. ADP-ribosylation of hnRNPs may thus serve to modulate the activity of these proteins in the nucleus.
Prasad
S
S
Department of Radiation Medicine, Georgetown University Medical Center, Washington, DC 20007.
Walent
J
J
Dritschilo
A
A
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000595:Amino Acid Sequence; D015180:Electrophoresis, Gel, Two-Dimensional; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009243:NAD; D016601:RNA-Binding Proteins / Q000378:metabolism; D012261:Ribonucleoproteins / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
D016601:RNA-Binding Proteins; D012261:Ribonucleoproteins; D009243:NAD; D000246:Adenosine Diphosphate Ribose