Haskin C L, Athanasiou K A, Klebe R, Cameron I L
Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio.
Biochem Cell Biol. 1993 Jul-Aug;71(7-8):361-71. doi: 10.1139/o93-054.
Human osteosarcoma cells, MG-63, were exposed to a hydrostatic pressure shock of 4.0 MPa for 20 min. Changes in subcellular distribution of the cytoskeletal elements and heat shock protein 70 (hsp70) were followed by indirect immunofluorescence and by avidin-biotin-peroxidase protocols. During recovery, total cellular RNA was determined and actin and aldolase mRNA content was followed using reverse transcription-polymerase chain reaction techniques. Hydrostatic pressure caused cell rounding (but not cell death), disruption of microtubules, collapse of intermediate filaments to a perinuclear location, collapse of actin stress fibers into globular aggregates in the cytoplasm, and the formation of several large elongated intranuclear actin inclusions. During recovery, the cells flattened, reorganized microtubules, and redistributed intermediate filaments prior to the reappearance of actin stress fibers. At 20 and 60 min following the initiation of hydrostatic pressure, there was increased anti-hsp 70 staining at the nuclear membrane and concentration of hsp70 in four to six granules in the nucleus. At 120 min following the hydrostatic pressure, hsp70 showed intense staining in the cytoplasm and hsp70-containing granules in the nucleus disappeared. Cellular RNA decreased during the first 120-min posthydrostatic pressure shock and then recovered to near prehydrostatic pressure treatment levels by 240 min. Actin mRNA abundance, in relation to aldolase mRNA abundance, showed the same temporal pattern of initial decrease, followed by increase as did total RNA. Review of the literature indicated that eukaryotic cells respond to heat shock and to hydrostatic pressure by disruption of the cytoskeletal elements and by similar modifications in genetic expression. In this study, the observed responses of MG-63 cells to a 4-MPa hydrostatic pressure shock was like the reported response of mammalian cells to a 43 degrees C heat shock.
将人骨肉瘤细胞MG-63置于4.0兆帕的流体静压冲击下20分钟。通过间接免疫荧光和抗生物素蛋白-生物素-过氧化物酶方法追踪细胞骨架成分和热休克蛋白70（hsp70）亚细胞分布的变化。在恢复过程中，测定总细胞RNA，并使用逆转录-聚合酶链反应技术追踪肌动蛋白和醛缩酶mRNA含量。流体静压导致细胞变圆（但未导致细胞死亡）、微管破坏、中间丝向核周位置塌陷、肌动蛋白应力纤维在细胞质中塌缩成球状聚集体，以及在细胞核内形成几个大的细长肌动蛋白包涵体。在恢复过程中，细胞变平，重新组织微管，并在肌动蛋白应力纤维重新出现之前重新分布中间丝。在流体静压开始后的20分钟和60分钟，核膜处的抗hsp 70染色增加，细胞核中四到六个颗粒中的hsp70浓度升高。在流体静压后120分钟，hsp70在细胞质中显示强烈染色，细胞核中含hsp70的颗粒消失。在流体静压冲击后的前120分钟内，细胞RNA减少，然后在240分钟时恢复到接近流体静压处理前的水平。与醛缩酶mRNA丰度相关的肌动蛋白mRNA丰度显示出与总RNA相同的时间模式，即最初下降，随后上升。文献综述表明，真核细胞通过破坏细胞骨架成分和类似的基因表达修饰来响应热休克和流体静压。在本研究中，观察到的MG-63细胞对4兆帕流体静压冲击的反应与报道的哺乳动物细胞对43摄氏度热休克的反应相似。
