Plakidou-Dymock S, McGivan J D
Department of Agricultural Sciences, University of Bristol, Long Ashton Research Station, UK.
Biochim Biophys Acta. 1994 Nov 10;1224(2):189-97. doi: 10.1016/0167-4889(94)90190-2.
Amino acid deprivation of the bovine renal epithelial cell line NBL-1 led to a range of responses by the heat shock and glucose regulated stress proteins. The classic heat shock induction of HSP 72 was found to be mimicked, without prior heat stress, by phenylalanine addition to cells simultaneously deprived of all other amino acids. Co-inclusion of alanine prevented the HSP 72 induction by phenylalanine but not that caused by heat stress. Phenylalanine also increased expression of HSP 70 mRNA in cells simultaneously deprived of other amino acids. The glucose regulated protein GRP 75 was increased upon amino acid deprivation. GRP94 was detectable in a 50 kDa form in control cells but was detected as a 94 kDa form upon amino acid deprivation which was further enhanced upon inclusion of phenylalanine. Addition of alanine to the starvation medium led to detection of the 50 kDa form only. Amino acid deprivation appears to mimic the glucose deprivation stress response. Inclusion of phenylalanine during amino acid deprivation leads to a stress response similar to that of heat shock in terms of HSP 72 induction. However, the two inducers are sensitive to different repression signals since only the phenylalanine-signal was subject to nihilation by alanine co-inclusion.
对牛肾上皮细胞系NBL-1进行氨基酸剥夺处理，会引发热休克蛋白和葡萄糖调节应激蛋白的一系列反应。研究发现，在同时剥夺所有其他氨基酸的细胞中添加苯丙氨酸，无需预先进行热应激，就能模拟经典的热休克诱导HSP 72的过程。同时添加丙氨酸可阻止苯丙氨酸诱导HSP 72，但不能阻止热应激诱导的HSP 72。苯丙氨酸还会增加同时剥夺其他氨基酸的细胞中HSP 70 mRNA的表达。氨基酸剥夺后，葡萄糖调节蛋白GRP 75的表达增加。在对照细胞中，GRP94以50 kDa的形式可检测到，但在氨基酸剥夺后则以94 kDa的形式被检测到，添加苯丙氨酸后进一步增强。向饥饿培养基中添加丙氨酸只会导致检测到50 kDa的形式。氨基酸剥夺似乎模拟了葡萄糖剥夺应激反应。在氨基酸剥夺期间添加苯丙氨酸会导致在HSP 72诱导方面与热休克类似的应激反应。然而，这两种诱导剂对不同的抑制信号敏感，因为只有苯丙氨酸信号会因同时添加丙氨酸而被消除。
