Macrophage-melanocyte heterokaryons. II. The activation of macrophage DNA synthesis. Studies with inhibitors of RNA synthesis.
Macrophage-melanocyte heterokaryons. II. The activation of macrophage DNA synthesis. Studies with inhibitors of RNA synthesis.
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DOI：
10.1084/jem.133.2.321
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发表时间：
1971-02-01
影响因子：
15.3
通讯作者：
COHN, Z
中科院分区：
文献类型：
--
作者：
GORDON, S;COHN, Z
将在体外不合成DNA的小鼠腹腔巨噬细胞与黑素细胞融合，黑素细胞是一种在体外快速增殖的小鼠细胞株。融合后2-3小时，在巨噬细胞核中诱导DNA合成，并且无论每个异核体中每个黑素细胞核中存在的巨噬细胞核的数量如何，都发生DNA合成。50-80%的巨噬细胞核在融合后3-7小时内启动DNA合成。大多数11-12日龄鸡红细胞核在黑素细胞胞质中的激活时间超过10小时，在DNA合成前的延迟可能反映了每个核的异染色质含量。放线菌素的研究表明，异核体RNA合成对于随后的巨噬细胞DNA合成至关重要。这种RNA在DNA合成前1-4小时合成，不太可能是核糖体RNA，因为它对<0.1 µg/ml的放线菌素不敏感。在与放线菌素和溴结核菌素融合之前，对黑素细胞和巨噬细胞进行处理，以更有选择性地抑制RNA合成。用5 μg/ml放线菌素预处理1小时的巨噬细胞在融合后的前4小时显示出低于对照RNA合成的20%，但巨噬细胞DNA合成的正常激活。用5 μg/ml溴结核菌素（一种可逆的RNA合成抑制剂）预处理黑素细胞3-7小时，可阻止巨噬细胞DNA合成，而不影响异核体中巨噬细胞RNA合成（对照的81%）。这些研究表明，只有黑素细胞RNA的合成是必不可少的巨噬细胞DNA的生产。在融合前将一个细胞伴侣暴露于放线菌素导致融合后未处理的细胞核的交叉毒性。溴杀结核菌素是一种掺入RNA中的腺苷类似物，融合后不会产生这种交叉毒性。一旦巨噬细胞核在异核体中被激活，它对放线菌素的作用就变得不那么敏感。
Mouse peritoneal macrophages, which do not synthesize DNA in vitro, were fused with melanocytes, a mouse cell strain which proliferates rapidly in vitro. DNA synthesis was induced in macrophage nuclei 2–3 hr after fusion and occurred irrespective of the number of macrophage nuclei present per melanocyte nucleus in each heterokaryon. 50–80% of macrophage nuclei initiated DNA synthesis in the 3–7 hr period after fusion. The activation of most 11–12-day chick red cell nuclei in melanocyte cytoplasm took longer than 10 hr. The lag before DNA synthesis may reflect the heterochromatin content of each nucleus. Studies with actinomycin showed that heterokaryon RNA synthesis was essential for subsequent macrophage DNA synthesis. This RNA was synthesized 1–4 hr before the DNA and was unlikely to be ribosomal RNA, since it was insensitive to <0.1 µg/ml actinomycin. Melanocytes and macrophages were treated before fusion with actinomycin and bromotubercidin to bring about a more selective inhibition of RNA synthesis. Macrophages pretreated for 1 hr with 5 µg/ml of actinomycin showed less than 20% of control RNA synthesis in the first 4 hr after fusion, but a normal activation of macrophage DNA synthesis. Pretreatment of melanocytes for 3–7 hr with 5 µg/ml bromotubercidin, a reversible inhibitor of RNA synthesis, prevented macrophage DNA synthesis without affecting macrophage RNA synthesis in the heterokaryons (81% of control). These studies showed that only melanocyte RNA synthesis was essential for the production of macrophage DNA. The exposure of one cell partner to actinomycin before fusion caused cross-toxicity of the untreated nucleus after fusion. Bromotubercidin, an adenosine analogue which is incorporated into RNA, did not give rise to such cross-toxicity after fusion. Once the macrophage nucleus becomes activated in the heterokaryon it becomes less sensitive to the action of actinomycin.
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巨噬细胞螺旋细胞异源性。 I.制备和特性。
影响因子：
15.3
作者：
GORDON, S;COHN, Z
通讯作者：
COHN, Z
单核吞噬细胞的起源和动力学。
影响因子：
15.3
作者：
van Furth, R;Cohn, Z A
通讯作者：
Cohn, Z A
影响因子：
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作者：
Cohn, Z. A.
通讯作者：
Cohn, Z. A.
影响因子：
3.7
作者：
RINGERTZ, NR;DARZYNKIEWICZ, Z;BOLUND, L
通讯作者：
BOLUND, L
影响因子：
3.7
作者：
OKADA, Y;MURAYAMA, F;YAMADA, K
通讯作者：
YAMADA, K