U. Oster et al., OCCURRENCE OF HSP70 FRAGMENTS IN SEVERAL DEVELOPMENTAL STAGES OF ARABIDOPSIS-THALIANA, Journal of plant physiology, 145(4), 1995, pp. 465-469
Extracts of seeds, leaves, flowers, and green (unripe) and yellow (rip
e) fruits of Arabidopsis thaliana were investigated with anti-HSP70 an
tisera and affinity chromatography on ATP-agarose. Besides HSP70, a ba
nd sized about 35 kDa was found in fruits and seeds but not in other t
issues. This band reacts strongly with an antiserum that is directed a
gainst a C-terminal HSP70 sequence. This 35 kDa band is not bound to A
TP-agarose. Elution of the ATP-agarose with ATP resulted only in the H
SP70 protein (apparent size 65 kDa), which occurs in about equal amoun
ts in all organs. Subsequent elution with urea resulted in a 75 kDa pr
otein reacting with an anti-HSP70 antiserum. This <<HSP75>> occurs mai
nly in flowers and green fruit. Only trace amounts of this protein wer
e found in ripe fruits and seeds: N-terminal fragments (50 kDa and 35
kDa) are found in these organs instead. The role of the C-terminal 35
kDa fragment occurring in fruits and seeds is discussed.