Poly(ADP-ribosyl)ation of Histone H1 Correlates with Internucleosomal DNA Fragmentation during Apoptosis

Abstract

The biochemical role of poly(ADP-ribosyl)ation on internucleosomal DNA fragmentation associated with apoptosis was investigated in HL 60 human premyelocytic leukemia cells. It was found that UV light and chemotherapeutic drugs including adriamycin, mitomycin C, and cisplatin increased poly(ADP-ribosyl)ation of nuclear proteins, particularly histone H1. A poly(ADP-ribose) polymerase inhibitor, 3-aminobenzamide, prevented both internucleosomal DNA fragmentation and histone H1 poly(ADP-ribosyl)ation in cells treated with the apoptosis inducers. When nuclear chromatin was made accessible to the exogenous nuclease in a permeabilized cell system, chromatin of UV-treated cells was more susceptible to micrococcal nuclease than the chromatin of control cells. Suppression of histone H1 poly-(ADP-ribosyl)ation by 3-aminobenzamide reduced the micrococcal nuclease digestibility of internucleosomal chromatin in UV-treated cells. These results suggest that the poly(ADP-ribosyl)ation of histone H1 correlates with the internucleosomal DNA fragmentation during apoptosis mediated by DNA damaging agents. This suggestion is supported by the finding that xeroderma pigmentosum cells which are defective in introducing incision at the site of DNA damage, failed to induce DNA fragmentation as well as histone H1 poly(ADP-ribosyl)ation after UV irradiation. We propose that poly(ADPribosyl)ation of histone H1 protein in the early stage of apoptosis facilitates internucleosomal DNA fragmentation by increasing the susceptibility of chromatin to cellular endonuclease.Apoptosis is an active form of cellular suicide, a process that typically involves morphological changes such as the condensation of chromatin into clumps, nuclear fragmentation, and packaging of nuclear fragments into membrane-enclosed apoptotic bodies. These morphological changes are usually accompanied by biochemical changes including elevation of cytoplasmic Ca 2ϩ and internucleosomal DNA fragmentation (1). Many of the chemotherapeutic drugs and radiation which cause DNA damage are known to induce apoptosis (2-5). It is well established that a variety of DNA damaging agents lower the cellular NAD ϩ content by raising the specific activity of poly(ADPribose) polymerase (PARP) 1 (EC 2.4.2.30) that results from the conformational changes which occur when the zinc finger domains of the enzyme bind to the DNA strand breaks (6, 7). PARP is a nuclear enzyme which transfers the ADP-ribose moiety of NAD ϩ to nuclear proteins including PARP itself and histones in cells (8). In vitro studies have also revealed that topoisomerase I (9), RNA polymerase II (10), DNA polymerase ␣ (11), DNA polymerase ␤ (12), and terminal deoxynucleotidyl transferase (13) are the substrates of PARP. Thus, poly(ADPribosyl)ation has been implicated in many biological responses including DNA replication (14), DNA excision repair (15), cell differentiation (16), and tumor promotion (17).In recent years, the role of poly(ADP-ribosyl)ation in the cell death process has been discussed. The decrease in cellular PARP ...

Tanshinone IIA, an ingredient of Salvia miltiorrhiza BUNGE, induces apoptosis in human leukemia cell lines through the activation of caspase-3

“…Human promyelocytic leukemic cell line, HL60, was treated with various concentrations of tanshinone IIA for 4 h, and it was found that tanshinone IIA induced internucleosomal DNA fragmentation into the multiples of 180 bp at the concentration of 1 µg/ ml (Figure 2). UV radiation was used as a positive control for the induction of apoptosis (Yoon et al, 1996). In time course experiment in which 3 µg/ml of Tanshinone IIA was treated, 180 bp DNA ladder was generated 2 h after the treatment (Figure 3).…”

Downmodulation of ERK activity inhibits the proliferation and induces the apoptosis of primary acute myelogenous leukemia blasts

“…It is interesting to note that a biological anti-ERK approach to control neoplastic transformation exploits mechanisms such as PARP cleavage, utilized by common chemotherapeutic agents. 33,34 PARP has been demonstrated to be a useful target for enhancing the cytotoxicity of several drugs. 35 In fact, PARP is cleaved into 89 and 24 kDa fragments that contain the active site and the DNAbinding domain of the enzyme, respectively, during druginduced apoptosis in a variety of cells.…”

Temozolomide induces apoptosis and senescence in glioma cells cultured as multicellular spheroids

“…In collaboration with p53, PARP is a powerful activator of apoptosis. Active PARP can poly-ADP-ribosylate the histone H1 and thereby facilitate DNA fragmentation (Yoon et al, 1996). Inhibition of PARP on the other hand increases cellular susceptibility to alkylating agents by inhibiting DNA repair at the G1 checkpoint (Tentori et al, , 2001.…”