title: Hydroxyurea-induced replication stress causes poly(ADP-ribose) polymerase-2 accumulation and changes its intranuclear location in root meristems of Vicia faba.
abstract: Replication stress induced by 24 and 48h exposure to 2.5mM hydroxyurea (HU) increased the activity of poly(ADP-ribose) polymerase-2 (PARP-2; EC 2.4.2.30) in root meristem cells of Vicia faba. An increase in the number of PARP-2 foci was accompanied by their delocalization from peripheral areas to the interior of the nucleus. Our results indicate that the increase in PARP-2 was connected with an increase in S139-phosphorylated H2AX histones. The findings suggest the possible role of PARP-2 in replication stress. We also confirm that the intranuclear location of PARP-2 depends on the duration of HU-induced replication stress, confirming the role of PARP-2 as an indicator of stress intensity. Finally, we conclude that the more intense the HU-mediated replication stress, the greater the probability of PARP-2 activation or H2AXS139 phosphorylation, but also the greater the chance of increasing the efficiency of repair processes and a return to normal cell cycle progression.
authors.affiliation: Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90236 Łódź, Poland. Electronic address: dorota.rybaczek@gmail.com.
authors.forename: Dorota
authors.initials: D
authors.lastname: Rybaczek
mesh_terms: D002467:Cell Nucleus / Q000187:drug effects / Q000201:enzymology*; D004249:DNA Damage; D004261:DNA Replication / Q000187:drug effects*; D003720:Densitometry; D005453:Fluorescence; D006657:Histones / Q000378:metabolism; D006918:Hydroxyurea / Q000494:pharmacology*; D015151:Immunoblotting; D018519:Meristem / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D009685:Nuclear Envelope / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D010940:Plant Proteins / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D013312:Stress, Physiological / Q000187:drug effects*; D013997:Time Factors; D031307:Vicia faba / Q000187:drug effects / Q000201:enzymology*
chemical_list: D006657:Histones; D010940:Plant Proteins; D011065:Poly(ADP-ribose) Polymerases; D006918:Hydroxyurea
keywords: H2AX histone; Hydroxyurea; Poly(ADP-ribose) polymerase-2 (PARP-2); Replication stress; Vicia faba