Modification of membrane physical properties, biological response and insulin binding in Friend cells by low serum concentration.
Modification of membrane physical properties, biological response and insulin binding in Friend cells by low serum concentration.
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低血清浓度改变弗兰德细胞的膜物理特性、生物反应和胰岛素结合。
DOI：
10.1016/0005-2736(87)90176-3
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Ginsberg,BH
中科院分区：
文献类型：
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作者：
Simon,I;Brown,TJ;Ginsberg,BH
在三个Friend红白血病克隆中研究了低血清浓度对质膜流动性和脂质组成、分化和胰岛素结合的影响。当暴露于DMSO时，FLC（克隆号745）和F（+）（OstertagF 4 N）Friend红白血病细胞均可被诱导分化并产生血红蛋白。克隆R（3）（OstertagF 4-D5-1）在正常条件（15%血清）下生长时是DMSO抗性克隆，但在低血清浓度（2.5%血清）下生长时，在用DMSO诱导时可以经历分化，原卟啉IX积累。电子自旋共振测量有序参数S和S（T|表明R（3）的质膜比FLC和F（+）的质膜流动性更强。外超精细分裂S（T）的序参数|在37°C时，R（3）、F（+）和FLC的平均值分别为0.60 ± 0.009、0.62 ± 0.008和0.64 ± 0.009。我们已经使用胰岛素受体作为与Friend克隆的质膜相关的多肽激素受体的模型。胰岛素结合研究表明，R（3）受体对胰岛素的亲和力降低，表现为竞争一半示踪剂结合所需的胰岛素量增加10倍（R（3）为18 nM，FLC和F（+）为2 nM）。负协同模型的计算机拟合Scatchard图分析表明，R（3）与FLC或F（+）细胞具有相似的位点数/细胞（约70 000），具有相似的高亲和力和低亲和力。在低血清浓度下培养DMSO抗性克隆R（3），导致受体数量减少35%，受体亲和力增加，与可分化克隆相比。因此，在我们早期的报道中，DMSO抗性克隆的质膜和胰岛素受体的异常性质（Simon等（1984）Biochim. Biophys. Acta 803，39-47）通过使细胞在低血清浓度下生长而部分逆转，恢复细胞对分化剂的应答。
The effect of low serum concentration on plasma membrane fluidity and lipid composition, differentiation and insulin binding was investigated in three Friend erythroleukemia clones. Both FLC (clones No. 745) and F(+) (Ostertag F4N) Friend erythroleukemia cells can be induced to differentiate and to produce hemoglobin when exposed to DMSO. Clone R(3) (Ostertag F4-D5-1) is a DMSO-resistant clone when grown under normal conditions (15% serum) but could undergo differentiation with accumulation of protoporphyrin IX upon induction with DMSO when grown in low serum concentration (2.5% serum). Electron spin resonance measurements of the order parameters (S) andS(T|) demonstrate that R(3) has a more fluid plasma membrane than the FLC and F(+). The order parameters of the outer hyperfine splittingsS(T|) at 37°C are 0.60 ± 0.009, 0.62 ± 0.008 and 0.64 ± 0.009 for R(3), F(+) and FLC, respectively. We have used the insulin receptors as a model for a polypeptide hormone receptor associated with the plasma membrane of the Friend clones. Insulin binding studies demonstrated that the receptor of R(3) had a decreased affinity for insulin manifest as a 10-fold increase in the amount of insulin required to compete for half of the tracer binding (18 nM for R(3) vs. 2 nM for FLC and F(+)). Computer-fit Scatchard plot analysis by the negative cooperativity model reveal that R(3) possessed a similar number of sites/cell (about 70 000) as the FLC or F(+) cells, with similar high and low affinities. Growing the DMSO-resistant clone R(3) in low serum concentration caused a decrease in receptor number by 35%, and an increase in receptor affinity to that seen with the differentiable clones. Thus, the abnormal properties of the plasma membrane and insulin receptor of the DMSO-resistant clone in our earlier report (Simon et al. (1984) Biochim. Biophys. Acta 803, 39–47) were partially reversed by growing the cells in a low serum concentration, restoring the cellular response to the differentiation agent.