Pentz M, Vatev R, Goldthwait D A
Nucleic Acids Res. 1986 Jul 11;14(13):5513-29. doi: 10.1093/nar/14.13.5513.
HeLa cell nuclei with DNA labeled with [3H] thymidine have been preincubated under varying conditions and then incubated with micrococcal nuclease. Aliquots, removed at increasing times, were analyzed for mononucleosomal size DNA and for acid-soluble DNA, the ratios were plotted and a slope was determined. Preincubation with ATP and a regenerating system increased the slope 2 fold. Optimum ATP concentrations were above 0.25 mM. The ATP effect was reversed by novobiocin. No inhibition of the ATP effect was observed with nalidixic acid, coumermycin, oxolinic acid, VM-26, aphidicolin, or 3 amino-benzamide. NAD or cAMP or cGMP had no effect with or without ATP. Other nucleoside triphosphates could substitute to varying degrees for ATP as could ATP analogues. Nuclei from log phase cells showed no ATP effect, but log phase cells, partially depleted of ATP by incubation with deoxyglucose, showed the effect. The effect was lost in nuclei on long-term storage. No evidence was found for differential degradation of core histones, histone H-1 or DNA, and there was no evidence of nucleosome sliding.
用[3H]胸苷标记DNA的HeLa细胞核在不同条件下进行预孵育,然后与微球菌核酸酶一起孵育。在不同时间取出等分试样,分析单核小体大小的DNA和酸溶性DNA,绘制比率并确定斜率。用ATP和再生系统预孵育可使斜率增加2倍。最佳ATP浓度高于0.25 mM。新生霉素可逆转ATP的作用。萘啶酸、香豆霉素、恶喹酸、VM - 26、阿非迪霉素或3 -氨基苯甲酰胺未观察到对ATP作用的抑制。无论有无ATP,NAD、cAMP或cGMP均无作用。其他核苷三磷酸以及ATP类似物可不同程度地替代ATP。对数期细胞的细胞核未显示ATP作用,但通过与脱氧葡萄糖孵育而部分耗尽ATP的对数期细胞显示出该作用。该作用在细胞核长期储存后丧失。未发现核心组蛋白、组蛋白H - 1或DNA有差异降解的证据,也没有核小体滑动的证据。