S. Krobitsch et al., LEISHMANIA-DONOVANI HEAT-SHOCK-PROTEIN-100 - CHARACTERIZATION AND FUNCTION IN AMASTIGOTE STAGE DIFFERENTIATION, The Journal of biological chemistry, 273(11), 1998, pp. 6488-6494
We report the cloning and molecular analysis of the Leishmania donovan
i clpB gene. The protein-coding region is highly conserved compared wi
th its L. major homologue, while 5'-and 3'-flanking DNA sequences disp
lay 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, Hs
p100, becomes abundant only during sustained heat stress, but not unde
r common chemical stresses, Hsp100 associates into trimeric complexes
and is found mostly in a cytoplasmic, possibly membrane-associated loc
alization as deter mined by immune electron microscopy. Hsp100 shows i
mmediate early expression kinetics during axenic amastigote developmen
t, In its absence, expression of at least one amastigote stage-specifi
c protein family is impaired.