Milner C M, Campbell R D
Department of Biochemistry, University of Oxford, England.
Immunogenetics. 1990;32(4):242-51. doi: 10.1007/BF00187095.
A duplicated locus encoding the major heat shock-induced protein HSP70 is located in the major histocompatibility complex (MHC) class III region 92 kilobases (kb) telomeric to the C2 gene. Nucleotide sequence analysis of the two intronless genes, HSP70-1 and HSP70-2, has shown that they encode an identical protein product of 641 amino acids. A third intronless gene, HSP70-Hom, has also been identified 4 kb telomeric to the HSP70-1 gene. This encodes a more basic protein of 641 amino acids which has 90% sequence similarity with HSP70-1. In order to investigate the expression of the three (MHC)-linked HSP70 genes individually by northern blot analysis, we have isolated locus-specific probes from the 3' untranslated regions of the genes. The HSP70-1 and HSP70-2 genes have been shown to be expressed at high levels as a approximately 2.4 kb mRNA in cells heat-shocked at 42 degrees C. HSP70-1 is also expressed constitutively at very low levels. The HSP70-Hom gene, which has no heat shock consensus sequence in its 5' flanking sequence, is expressed as a approximately 3 kb mRNA at low levels both constitutively and following heat shock.
一个编码主要热休克诱导蛋白HSP70的重复基因座位于主要组织相容性复合体（MHC）III类区域，在C2基因的端粒方向92千碱基（kb）处。对两个无内含子基因HSP70 - 1和HSP70 - 2的核苷酸序列分析表明，它们编码一种由641个氨基酸组成的相同蛋白质产物。第三个无内含子基因HSP70 - Hom也已在HSP70 - 1基因的端粒方向4 kb处被鉴定出来。它编码一种由641个氨基酸组成的碱性更强的蛋白质，与HSP70 - 1有90%的序列相似性。为了通过Northern印迹分析单独研究这三个与MHC相关的HSP70基因的表达情况，我们从这些基因的3'非翻译区分离出了基因座特异性探针。已证明HSP70 - 1和HSP70 - 2基因在42℃热休克的细胞中以大约2.4 kb的mRNA高水平表达。HSP70 - 1也以非常低的水平组成性表达。HSP70 - Hom基因在其5'侧翼序列中没有热休克共有序列，在组成性表达以及热休克后均以大约3 kb的mRNA低水平表达。
