Reprogramming cellular events by poly(ADP-ribose)-binding proteins.

Poly(ADP-ribosyl)ation is a posttranslational modification catalyzed by the poly(ADP-ribose) polymerases (PARPs). These enzymes covalently modify glutamic, aspartic and lysine amino acid side chains of acceptor proteins by the sequential addition of ADP-ribose (ADPr) units. The poly(ADP-ribose) (pADPr) polymers formed alter the physico-chemical characteristics of the substrate with functional consequences on its biological activities.

PARP1 parylation promotes silent locus transmission in the nucleolus: the suspicion confirmed.

Parylation modulates various processes, including transcription. In this issue of Molecular Cell, Guetg et al. (2012) show that, in the nucleolus, PARP1-mediated parylation of TIP5 promotes the silencing of rDNA chromatin during replication, uncovering the mechanism by which PARP1 ensures that silent rDNA regions are properly inherited.

Mass spectrometry-based functional proteomics of poly(ADP-ribose) polymerase-1.

PARP-1 is an abundant nuclear protein that plays an essential role in the regulation of many genome integrity and chromatin-based processes, such as DNA repair, replication or transcriptional regulation. PARP-1 modulates the function of chromatin and nuclear proteins through several poly(ADP-ribose) (pADPr)-dependent pathways. Aside from the clearly established role of PARP-1 in the maintenance of genome stability, PARP-1 also emerged as an important regulator that links chromatin functions with extranuclear compartments.

Comparative immunogenicity under field conditions of two recombinant hepatitis B vaccines in 8-10-year-old children.

The immunogenicity of two hepatitis B vaccines was compared in 8-10-year-old children immunized in a school program. One year apart, 1129 children received Engerix-B 10 microg vaccine (EB), and 1126 received Recombivax-HB 2.5 microg (RB), following the 0, 1, 6 schedule.

Dopamine D3 receptor antisense administration reduces basal c-fos and NGFI-B mRNA levels in the rat forebrain.

The physiological role of the dopamine D3 receptor is still unclear. The absence of selective pharmacological tools that can discriminate D3 over D2 receptor subtype activity is a major drawback in the elucidation of D3-mediated functions. In order to study D3 receptor actions in rat brain, we have developed an antisense strategy, using oligodeoxynucleotide (ODN) directed against the mRNA of the D3 receptor.

Increased resistance of GPx-1 transgenic mice to tumor promoter-induced loss of glutathione peroxidase activity in skin.

Reactive oxygen species formation is strongly suspected to play a role in multistep carcinogenesis, notably in tumor promotion. The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) induces peroxide production, oxidative damage to DNA and inflammation in mouse skin. TPA is also known to cause a decrease in the activity of several antioxidant enzymes including glutathione peroxidases (GPx).

Dopamine D3 receptor antisense reduces neuropeptide mRNA levels in rat nucleus accumbens.

We have investigated the effects of a dopamine D3 receptor antisense oligodeoxynucleotide (ODN), on neurotensin and dynorphin mRNA levels in rat nucleus accumbens. Intracerebroventricular injections of ODNs were made into the lateral ventricle (5 and 10 microg h(-1), for 5 days). Receptor autoradiography of dopamine D2 and D3 receptor subtypes was performed.