Evidence of poly(ADP-ribosylation) in the cockroach Periplaneta americana

Poly(ADP-ribosylation) is a post-translational modification of nuclear prot eins typical of most eukaryotic cells. This process participates in DNA rep lication and repair and is mainly regulated by two enzymes, poly(ADP-ribose ) polymerase, which is responsible for the synthesis of polymers of ADP-rib ose, and poly(ADP-ribose) glycohydrolase, which performs polymer degradatio n. The aim of this work was to investigate in the cockroach Periplaneta ame ricana L. (Blattaria: Blattidae) the behaviour of poly(ADP-ribosylation). I n particular, we addressed: (i) the possible modulation of poly(ADP-ribosyl ation) during the embryonic development; (ii) the expression of poly(ADP-ri bose) polymerase and glycohydrolase in different tissues; and (iii) the rol e of poly(ADP-ribosylation) during spermatogenesis. In this work we demonst rated that: (i) as revealed by specific biochemical assays, active poly(ADP -ribose) polymerase and glycohydrolase are present exclusively in P. americ ana embryos at early stages of development; (ii) an activity carrying out p oly(ADP-ribose) synthesis was found in extracts from testes; and (iii) the synthesis of poly(ADP-ribose) occurs preferentially in differentiating sper matids/spermatozoa. Collectively, our results indicate that the poly(ADP-ribosylation) process in P. americana, which is a hemimetabolous insect, displays catalytical and structural features similar to those described in the holometabolous insec ts and in mammalian cells. Further more, this process appears to be modulat ed during embryonic development and spermatogenesis. (C) 2000 Elsevier Scie nce Ltd. All rights reserved.