+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Abscisic acid-induced heat tolerance in Bromus inermis Leyss cell-suspension cultures. Heat-stable, abscisic acid-responsive polypeptides in combination with sucrose confer enhanced thermostability

, : Abscisic acid-induced heat tolerance in Bromus inermis Leyss cell-suspension cultures. Heat-stable, abscisic acid-responsive polypeptides in combination with sucrose confer enhanced thermostability. Plant Physiology 105(1): 181-190

Increased heat tolerance is most often associated with the synthesis of heat-shock proteins following pre-exposure to a nonlethal heat treatment. In this study, a bromegrass (Bromus inermis Leyss cv Manchar) cell suspension cultured in a medium containing 75 micromolar abscisic acid (ABA) without prior heat treatment had a 87% survival rate, as determined by regrowth analysis, following exposure to 42.5 degrees C for 120 min. In contrast, less than 1% of the control cells survived this heat treatment. The heat tolerance provided by treatment with 75 gm ABA was first evidenced after 4 d of culture and reached a maximum tolerance after 11 d of culture. Preincubation with sucrose partially increased the heat tolerance of control cells and rendered ABA-treated cells tolerant to 45 degrees C for 120 min (a completely lethal heat treatment for control cells). Comparative two-dimensional polyacrylamide gel electrophoresis of cellular protein isolated from heat-tolerant cells identified 43 ABA-responsive proteins of which 26 were heat stable (did not coagulate and remained soluble after 30 min at 90 degrees C). Eight heat-stable, ABA-responsive proteins ranging from 23 to 45 kD had similar N-terminal sequences. The ABA-responsive (43-20 kD), but none of the control heat-stable, proteins cross-reacted to varying degrees with a polyclonal antibody directed against a conserved, lysine-rich dehydrin sequence. A group of 20- to 30-kD heat-stable, ABA-responsive proteins cross-reacted with both the anti-dehydrin antibody and an antibody directed against a cold-responsive winter wheat protein (Wcs 120). In ABA-treated cells, there was a positive correlation between heat- and pH-induced coagulation of a cell-free homogenate and the heat tolerance of these cells. At 50 degrees C, control homogenates coagulated after 8 min, whereas cellular fractions from ABA-treated cells showed only marginal coagulation after 15 min. In protection assays, addition of heat-stable, ABA-responsive polypeptides to control fractions reduced the heat-induced coagulation of cell-free homogenates. Sucrose (8%) alone and control, heat-stable fractions enhanced the thermostability of control fractions, but the most protection was conferred by ABA-responsive, heat-stable proteins in combination with sucrose. These data suggest that stress-tolerance mechanisms may develop as a result of cooperative interactions between stress proteins and cell osmolytes, e.g. sucrose. Hypotheses are discussed implicating the role of these proteins and osmolytes in preventing coagulation and denaturation of cellular proteins and membranes.


PMID: 8029349

DOI: 10.2307/4275821

Other references

Geers, R., 1981: Feed efficiency of R.I.R. -hens (Gallus gallus L.) as affected by pre- and postnatal environmental temperatures in relation to development, reproduction and intermediary metabolism. Agricultura 9(4): 497-609

Retzinger E.J.Jr, 1984: Growth and development of sicklepod cassia obtusifolia selections. Sicklepod (Cassia obtusifolia L. #3 CASOB) seed were obtained from 10 locations in 9 southern states [USA], and plants were grown in a nursery for 3 yr. In field experiments, plant height, seed per pod, number of seed per plant and number of pods...

Eisenman, D.J.; Speers, R.; Telian, S.A., 2001: Labyrinthectomy versus vestibular neurectomy: long-term physiologic and clinical outcomes. To determine whether long-term vestibular compensation (VC) and clinical outcomes differ after transmastoid labyrinthectomy (TML) versus retrolabyrinthine vestibular neurectomy (RVNS). Prospective, observational study. Tertiary care, university ho...

Pioped Invest (Usa), 1990: Tissue plasminogen activator for the treatment of acute pulmonary embolism. Thirteen patients with acute pulmonary embolism were treated in a randomized double-blind fashion either with recombinant tissue plasminogen activator (rt-PA) 40 to 80 mg, usually in combination with heparin, or with placebo plus heparin. The drug...

Oborotova, N.A., 2001: Results of creating domestic medicinal forms of antineoplastic agents at the N. N. Blokhin Cancer Research Center of the Russian Academy of Medical Sciences. Since there is a rise in morbidity and mortality rates due to malignant neoplasms, their drug therapy along with radiation and surgical methods remains a burning problem of modern medicine. Empirical and rational approaches to searching for new dr...

D.H.rtogh R.; Ekka E.; Vanderheyden I., 1980: Estradiol 17 beta receptors in the uterus of long term streptozotocin induced diabetic rat correlation with the induction of early protein synthesis. Diabetologia 19(3): 268-269

Henry M.; Karig D.E.; Shor G.G.J., 1975: Two seismic refraction profiles in the West Philippine Sea. Initial Reports of the Deep Sea Drilling Project 31(Apra, Guam to Hakodate, Japan(June-August 1973): 611-614

Schipper, I.A.; Kotta, P.; Staples, G.E.; Fisher, G.R.; Erickson, G.M., 1981: Immunoglobulin-G content in bovine colostrum preserved by freezing, fermentation and chemical preservatives. Preservation of immunoglobulin in stored bovine colostrum is best achieved by freezing for at least 8 weeks. Fermentation at ambient temperatures was nearly as effective as freezing for 6 weeks.

Anonymous, 2004: Are you an especially qualified family practitioner?. Mmw Fortschritte der Medizin 146(18): 54-54

Granit, R.; Renkin, B., 1961: Net depolarization and discharge rate of motoneurones, as measured by recurrent inhibition. In decerebrate de-efferented cats single-fibre reflexes, in response to maintained tetanus of the gastrocnemius nerves, have been recorded from appropriate ventral roots. Their discharge rate has been suppressed by antidromic tetanization of the r...