Tissue-specific expression of sunflower heat shock proteins in response to water stress

1993 ◽  
Vol 4 (6) ◽  
pp. 947-958 ◽  
Author(s):  
Concepcion Almoguera ◽  
Maria A. Coca ◽  
Juan Jordano
1984 ◽  
Vol 99 (4) ◽  
pp. 1316-1323 ◽  
Author(s):  
R Morimoto ◽  
E Fodor

We have found that chicken reticulocytes respond to elevated temperatures by the induction of only one heat shock protein, HSP70, whereas lymphocytes induce the synthesis of all four heat shock proteins (89,000 mol wt, HSP89; 70,000 mol wt, HSP70; 23,000 mol wt, HSP23; and 22,000 mol wt, HSP22). The synthesis of HSP70 in lymphocytes was rapidly induced by small increases in temperature (2 degrees-3 degrees C) and blocked by preincubation with actinomycin D. Proteins normally translated at control temperatures in reticulocytes or lymphocytes were not efficiently translated after incubation at elevated temperatures. The preferential translation of mRNAs that encode the heat shock proteins paralleled a block in the translation of other cellular proteins. This effect was most prominently observed in reticulocytes where heat shock almost completely repressed alpha- and beta-globin synthesis. HSP70 is one of the major nonglobin proteins in chicken reticulocytes, present in the non-heat-shocked cell at approximately 3 X 10(6) molecules per cell. We compared HSP70 from normal and heat-shocked reticulocytes by two-dimensional gel electrophoresis and by digestion with Staphylococcus aureus V8 protease and found no detectable differences to suggest that the P70 in the normal cell is different from the heat shock-induced protein, HSP70. P70 separated by isoelectric focusing gel electrophoresis into two major protein spots, an acidic P70A (apparent pl = 5.95) and a basic P70B (apparent pl = 6.2). We observed a tissue-specific expression of P70A and P70B in lymphocytes and reticulocytes. In lymphocytes, P70A is the major 70,000-mol-wt protein synthesized at normal temperatures whereas only P70B is synthesized at normal temperatures in reticulocytes. Following incubation at elevated temperatures, the synthesis of both HSP70A and HSP70B was rapidly induced in lymphocytes, but synthesis of only HSP70B was induced in reticulocytes.


2013 ◽  
Vol 14 (1) ◽  
pp. 135-148 ◽  
Author(s):  
Margarida Rocheta ◽  
Jörg D. Becker ◽  
João L. Coito ◽  
Luísa Carvalho ◽  
Sara Amâncio

1991 ◽  
Vol 69 (8) ◽  
pp. 2021-2027 ◽  
Author(s):  
Scott D. Dyer ◽  
Kenneth L. Dickson ◽  
Earl G. Zimmerman ◽  
Brenda M. Sanders

Qualitative and quantitative differences in the heat-shock response in brain, gill, and striated muscle tissues of the fathead minnow (Pimephales promelas) were investigated. The maximum sublethal heat-shock temperature was 34 °C. The heat-shock proteins (hsps) induced, their biosynthetic rates, minimum temperatures required for induction, and maximum temperatures at which each tissue synthesized hsps were tissue specific. Six hsps were induced in gill tissue (100, 90, 78, 70, 68, and 60 kDa), four in muscle tissue (100, 90, 78, and 70 kDa), and three in brain tissue (90, 70, and 68 kDa). Minimum temperatures required for inducing the stress response in gill, muscle, and brain were 28, 31, and 32 °C, respectively. Maximum hsp synthesis and accumulation occurred at 33 °C for the brain and 34°C for muscle and gill. Synthesis and accumulation of hsps decreased to near pre-exposure levels in the brain at 34 °C. The fact that brain tissue synthesized the fewest hsps and had the lowest capacity for synthesis at the upper thermal limits of the organism supports the hypothesis that the central nervous system governs the thermal limits to survival in poikilotherms.


2019 ◽  
Vol 201 (12) ◽  
Author(s):  
Ritesh Rajesh Sevalkar ◽  
Divya Arora ◽  
Prabhat Ranjan Singh ◽  
Ranjeet Singh ◽  
Vinay K. Nandicoori ◽  
...  

ABSTRACT A hallmark feature of Mycobacterium tuberculosis pathogenesis lies in the ability of the pathogen to survive within macrophages under a stressful environment. Thus, coordinated regulation of stress proteins is critically important for an effective adaptive response of M. tuberculosis, the failure of which results in elevated immune recognition of the tubercle bacilli with reduced survival during chronic infections. Here, we show that virulence regulator PhoP impacts the global regulation of heat shock proteins, which protect M. tuberculosis against stress generated by macrophages during infection. Our results identify that in addition to classical DNA-protein interactions, newly discovered protein-protein interactions control complex mechanisms of expression of heat shock proteins, an essential pathogenic determinant of M. tuberculosis. While the C-terminal domain of PhoP binds to its target promoters, the N-terminal domain of the regulator interacts with the C-terminal end of the heat shock repressors. Remarkably, our findings delineate a regulatory pathway which involves three major transcription factors, PhoP, HspR, and HrcA, that control in vivo recruitment of the regulators within the target genes and regulate stress-specific expression of heat shock proteins via protein-protein interactions. The results have implications on the mechanism of regulation of PhoP-dependent stress response in M. tuberculosis. IMPORTANCE The regulation of heat shock proteins which protect M. tuberculosis against stress generated by macrophages during infection is poorly understood. In this study, we show that PhoP, a virulence regulator of the tubercle bacilli, controls heat shock-responsive genes, an essential pathogenic determinant of M. tuberculosis. Our results unravel that in addition to classical DNA-protein interactions, complex mechanisms of regulation of heat shock-responsive genes occur through multiple protein-protein interactions. Together, these findings delineate a fundamental regulatory pathway where transcription factors PhoP, HspR, and HrcA interact with each other to control stress-specific expression of heat shock proteins.


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