Sanchez G I, Carucci D J, Sacci J, Resau J H, Rogers W O, Kumar N, Hoffman S L
Department of Molecular Microbiology and Immunology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland, 21205, USA.
Exp Parasitol. 1999 Dec;93(4):181-90. doi: 10.1006/expr.1999.4455.
Heat shock proteins are a highly conserved group of proteins required for the correct folding, transport, and degradation of other proteins in vivo. The Hsp70, Hsp90, and Hsp60 families are among the most widely studied families. Hsp60 is found in eubacteria, mitochondria, and chloroplasts, where, in cooperation with Hsp10, it participates in protein folding and translocation of proteins to the organelles. We have cloned and characterized the Hsp60 gene of Plasmodium yoelii (PyHsp60). PyHsp60 is a single-copy gene, located on chromosome 9, 10, or 11. The PyHsp60 cDNA sequence showed an open reading frame of 1737 nucleotides that codes for a polypeptide of 579 amino acids, with 93% amino acid identity to Plasmodium-falciparum Hsp60 (PfHsp60). Cloning and sequencing of a genomic PCR clone showed the presence of a 201-bp intron, located 141 bp downstream of the ATG codon. A single, heat-inducible, 2.3-kb transcript was detected in Northern blots of RNA isolated from blood stage parasites. Mouse antisera raised against a DNA vaccine vector that expresses PyHsp60 recognized sporozoites and liver- and blood-stage parasites by indirect fluorescent antibody test (IFAT). By Western blot, these antisera reacted with the mycobacterial Hsp65 and recognized a protein of approximately 65 kDa in P. yoelii sporozoites and P. falciparum blood stages. These results show that PyHsp60 and PfHsp60 genes are homologous and that of the PyHsp60 gene encodes a heat-inducible, intracellular protein that is expressed in several of the developmental stages of P. yoelii.
热休克蛋白是体内其他蛋白质正确折叠、运输和降解所必需的一组高度保守的蛋白质。Hsp70、Hsp90和Hsp60家族是研究最为广泛的家族。Hsp60存在于真细菌、线粒体和叶绿体中，在那里它与Hsp10协同作用，参与蛋白质折叠以及蛋白质向细胞器的转运。我们已经克隆并鉴定了约氏疟原虫的Hsp60基因（PyHsp60）。PyHsp60是一个单拷贝基因，位于第9、10或11号染色体上。PyHsp60 cDNA序列显示有一个1737个核苷酸的开放阅读框，编码一个579个氨基酸的多肽，与恶性疟原虫Hsp60（PfHsp60）的氨基酸同一性为93%。一个基因组PCR克隆的克隆和测序显示存在一个201 bp的内含子，位于ATG密码子下游141 bp处。在从血液期寄生虫分离的RNA的Northern印迹中检测到一个单一的、热诱导的2.3 kb转录本。针对表达PyHsp60的DNA疫苗载体产生的小鼠抗血清通过间接荧光抗体试验（IFAT）识别子孢子以及肝期和血液期寄生虫。通过蛋白质印迹法，这些抗血清与分枝杆菌Hsp65反应，并在约氏疟原虫子孢子和恶性疟原虫血液期识别出一种约65 kDa的蛋白质。这些结果表明PyHsp60和PfHsp60基因是同源的，并且PyHsp60基因编码一种热诱导的细胞内蛋白质，该蛋白质在约氏疟原虫的几个发育阶段中表达。
