Leishmania donovani heat shock protein 100. Characterization and function in amastigote stage differentiation.
نویسندگان
چکیده
We report the cloning and molecular analysis of the Leishmania donovani clpB gene. The protein-coding region is highly conserved compared with its L. major homologue, while 5'- and 3'-flanking DNA sequences display considerable divergence. The encoded mRNA has an unusually long 5'-leader sequence typical for RNAs, which are translated preferentially under heat stress. The gene product, a 100-kDa heat shock protein, Hsp100, becomes abundant only during sustained heat stress, but not under common chemical stresses. Hsp100 associates into trimeric complexes and is found mostly in a cytoplasmic, possibly membrane-associated, localization as determined by immune electron microscopy. Hsp100 shows immediate early expression kinetics during axenic amastigote development. In its absence, expression of at least one amastigote stage-specific protein family is impaired.
منابع مشابه
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 273 11 شماره
صفحات -
تاریخ انتشار 1998