Purification of non-histone acceptor proteins for ADP-ribose from mouse testis nuclei.
Acceptor proteins for poly(ADP-ribose) have been purified from mouse testis nuclei. Nuclear proteins were labelled in vitro with [14C]ribose and [3H]adenine, extracted with 5% (v/v) HClO4 and 0.25 M-HCl and separated by ion-exchange chromatography. Non-histone proteins were found to be the major acceptors in both the 5% (w/v)-HClO4-soluble and 5%-HClO4-insoluble HCl-extractable fractions. Of the two groups of non-histone proteins associated with chromatin, the LMG (low-mobility-group) proteins were preferentially ADP-ribosylated. HMG (high-mobility group) proteins were labelled to lower specific radioactivity. Six LMG proteins were purified to approx. 90% homogeneity and were identified from their mobility on polyacrylamide gels at pH 2.9 and from their amino acid composition. The average length of the poly(ADP-ribose) chain was estimated to be four to six repeating ADP-ribose units. It is suggested that ADP-ribosylation of LMG proteins, a long-neglected group of chromatin-associated proteins, is important during spermatogenesis for the production of spermatozoa with intact and competent DNA.
D000246:Adenosine Diphosphate Ribose; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002467:Cell Nucleus / Q000032:analysis*; D002852:Chromatography, Ion Exchange; D002868:Chromosomal Proteins, Non-Histone / Q000302:isolation & purification*; D004591:Electrophoresis, Polyacrylamide Gel; D006609:High Mobility Group Proteins; D006997:Hypochlorous Acid; D008297:Male; D051379:Mice; D009702:Nucleoside Diphosphate Sugars; D043264:Phosphodiesterase I; D010727:Phosphoric Diester Hydrolases; D013737:Testis / Q000032:analysis*
D000596:Amino Acids; D002868:Chromosomal Proteins, Non-Histone; D006609:High Mobility Group Proteins; D009702:Nucleoside Diphosphate Sugars; D000246:Adenosine Diphosphate Ribose; D006997:Hypochlorous Acid; D010727:Phosphoric Diester Hydrolases; D043264:Phosphodiesterase I