Depurination of plant ribosomes by pokeweed antiviral protein.
Mammalian ribosomes have been shown to be enzymatically modified by ribosomal inactivating protein (RIPs) via specific depurination of rRNA. Here we report that ribosomes isolated from wheat germ contain intact and undepurinated rRNA and are depurinated by pokeweed antiviral protein (PAP). Pokeweed ribosomes isolated under the same conditions are depurinated. Total RNA isolated from pokeweed in the presence of strong denaturants was found to pbe partially depurinated. We conclude that wheat germ ribosomes are resistant to the endogenous RIP, tritin, but are sensitive to PAP and that pokeweed ribosomes can be depurinated by the N-glycosidase activity of endogenous PAP during isolation.
Taylor
B E
BE
Department of Chemistry, Southwest Texas State University, San Marcos 78666.
Irvin
J D
JD
D000998:Antiviral Agents / Q000494:pharmacology*; D001483:Base Sequence; D008969:Molecular Sequence Data; D009699:N-Glycosyl Hydrolases; D010940:Plant Proteins / Q000494:pharmacology*; D010944:Plants / Q000378:metabolism*; D011687:Purines; D012335:RNA, Ribosomal / Q000187:drug effects* / Q000302:isolation & purification; D054789:Ribosome Inactivating Proteins, Type 1; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism*; D014908:Triticum / Q000378:metabolism
D000998:Antiviral Agents; D010940:Plant Proteins; D011687:Purines; D012335:RNA, Ribosomal; D054789:Ribosome Inactivating Proteins, Type 1; D009699:N-Glycosyl Hydrolases; C024275:pokeweed antiviral protein