染色体1q12区域是基因组中最大的着丝粒周心异染色质区域，包括串联重复的卫星III DNA [SatIII (1)].在培养人体皮肤成纤维细胞（HSFs）的复制衰老过程中，发现SatIII (1)的拷贝数量增加。本研究旨在分析培养HSFs中SatIII (1)丰度的变化，其取决于内源性和外源性应激的水平。我们研究了10个HSF细胞系，其中高氧化应激水平者（来自精神分裂症患者，n = 5）和低氧化应激水平者（来自健康对照组，n = 5）。内源性应激水平通过反应性氧化物种、DNA损伤标志物（8-羟基-2'-脱氧鸟苷、γ-H2A 增殖素家族成员 X）、抗氧化蛋白（NADPH 氧化酶 4、超氧化物歧化酶 1、红细胞核 2 相关因子 2）和调节细胞凋亡和自噬的蛋白（B 淋巴瘤 2 [Bcl-2]、Bcl-2 关联的 X 蛋白、轻链 3）的数量来估计。使用非放射性定量杂交技术测量了SatIII (1)的拷贝数量。为了比较，还测定了端粒和核糖体RNA基因重复的含量。使用定量聚合酶链反应（PCR）测定了RNASATIII (1和9)的含量。在饱和HSFs中的DNA中，SatIII (1)的含量与氧化应激增加呈正相关。无培养基更换和热休克的饱和细胞培养导致DNA中SatIII (1)的减少，同时RNASATIII (1)的减少和RNASATIII (9)的增加。在HSF培养过程中，在夸张的氧化应激条件下，SatIII (1)含量增加的细胞在细胞群中积聚。在外源性应激的额外影响后，这部分细胞的比例减少。该过程似乎是振荡的。© 2023 The Author(s). Published by IMR Press.

The chromosome 1q12 region harbors the genome's largest pericentromeric heterochromatin domain that includes tandemly repeated satellite III DNA [SatIII (1)]. Increased SatIII (1) copy numbers have been found in cultured human skin fibroblasts (HSFs) during replicative senescence. The aim of this study was to analyze the variation in SatIII (1) abundance in cultured HSFs at early passages depending on the levels of endogenous and exogenous stress.We studied 10 HSF cell lines with either high (HSFs from schizophrenic cases, n = 5) or low (HSFs from healthy controls, n = 5) levels of oxidative stress. The levels of endogenous stress were estimated by the amounts of reactive oxygen species, DNA damage markers (8-hydroxy-2'-deoxyguanosine, gamma-H2A histone family member X), pro- and antioxidant proteins (NADPH oxidase 4, superoxide dismutase 1, nuclear factor erythroid 2-related factor 2), and proteins that regulate apoptosis and autophagy (B-cell lymphoma 2 [Bcl-2], Bcl-2-associated X protein, light chain 3). SatIII (1) copy numbers were measured using the nonradioactive quantitative hybridization technique. For comparison, the contents of telomeric and ribosomal RNA gene repeats were determined. RNASATIII (1 and 9) were quantified using quantitative Polymerase Chain Reaction (PCR).Increased SatIII (1) contents in DNA from confluent HSFs were positively correlated with increased oxidative stress. Confluent cell cultivation without medium replacement and heat shock induced a decrease of SatIII (1) in DNA in parallel with a decrease in RNASATIII (1) and an increase in RNASATIII (9).During HSF cultivation, cells with increased SatIII (1) content accumulated in the cell pool under conditions of exaggerated oxidative stress. This fraction of cells decreased after the additional impact of exogenous stress. The process seems to be oscillatory.© 2023 The Author(s). Published by IMR Press.