Saccharomyces cerevisiae Hsp104 and Escherichia coli ClpB are Hsp100 family AAA+ chaperones that provide stress tolerance by cooperating with Hsp70 and Hsp40 to solubilize aggregated protein. Hsp104 also remodels amyloid in vitro and promotes propagation of amyloid prions in yeast, but ClpB does neither, leading to a view that Hsp104 evolved these activities. Although biochemical analyses ident...

During parasitoid development, the immature parasitoid is confined to the host species. As a result, any potential to modify the physiology or behaviour of the host could play an important role in parasitoid fitness. The potential for host manipulation by the aphid parasitoid Aphidius avenae to increase cold thermotolerance was investigated using the aphid host species Metopolophium dirhodum an...

We previously reported that nitric oxide (NO) functions as a signal in thermotolerance. To illustrate its relationship with hydrogen peroxide (H₂O₂) in the tolerance of Arabidopsis (Arabidopsis thaliana) to heat shock (HS), we investigated the effects of heat on Arabidopsis seedlings of the following types: the wild type; three NADPH oxidase-defective mutants that exhibit reduced endogenous H₂O...

Hyperthermia - application of supra-physiological temperatures to cells, tissues or organs - is a pleiotropic treatment that affects most aspects of cellular metabolism, but its effects on DNA are of special interest in the context of cancer research and treatment. Hyperthermia inhibits repair of various DNA lesions, including double-strand breaks (DSBs), making it a powerful radio- and chemose...

The purpose of the present study was to test the possible plant thermotolerance role of isoprene and to study its relationship with non-enzymatic antioxidants and terpene emissions. The gas exchange, chlorophyll fluorescence, extent of photoand oxidative stress, leaf damage, mechanisms of photoand antioxidant protection, and terpene emission were measured in leaves of Quercus ilex seedlings exp...

A variety of diagnostic tests used by many laboratories to identify isolates of Wangiella dermatitidis (= Fonsecaea dermatitidis) were evaluated. Thirteeen isolates of W. dermatitidis were studied with respect to their ability to grow at 25, 37, 40, 45, and 50 degrees C, colonial and micromorphology, gelatin liquefaction, and hydrolysis of casein, xanthine, hypoxanthine, and tyrosine. All 13 is...

Much of the effect of heat stress on establishment and maintenance of pregnancy involves changes in ovarian function and embryonic development that reduce the competence of the oocyte to be fertilized and the resultant embryo to develop. There are three possible therapeutic approaches to manipulate the connection between hyperthermia and cellular responses to elevated temperature to improve fer...

27 To characterize the function of salicylic acid (SA) in acquired thermotolerance, the effects of heat 28 shock (HS) on wild-type and sid2 (for SA induction deficient 2) was investigated. After HS 29 treatment, the survival ratio of sid2 mutant was lower than that of wild-type. However, 30 pretreatment with hydrogen peroxide (H2O2) rescued the sid2 heat sensitivity. HsfA2 is a key 31 component...

In anticipation of using single or fractionated hyperthermia treatment in ex vivo purging of leukemic bone marrow in the clinic, we have compared the hyperthermic sensitivity, kinetics of thermotolerance, and heat-shock protein synthesis in three human myelogenous leukemic cell lines. In terms of heat sensitivity, the chronic myelogenous leukemic cell line K562 was found to be the most resistan...

Cullin4-RING ubiquitin ligase (CRL4) is a family of multi-subunit E3 ligases. To investigate the possible involvement of CRL4 in heat stress response, we screened T-DNA insertion mutants of putative CRL4 substrate receptors that exhibited altered patterns in response to heat stress. One of the mutants exhibited heat stress tolerance and was named heat stress tolerant DWD1 (htd1). Introduction o...