Conditioned aversion to distinct environmental stimuli resulting from gastrointestinal distress.

1973 ◽  
Vol 85 (2) ◽  
pp. 250-257 ◽  
Author(s):  
Phillip J. Best ◽  
Michael R. Best ◽  
G. Andrew Mickley
2020 ◽  
Vol 22 (1) ◽  
pp. 152
Author(s):  
Dorota Dabrowska ◽  
Justyna Mozejko-Ciesielska ◽  
Tomasz Pokój ◽  
Slawomir Ciesielski

Pseudomonas putida’s versatility and metabolic flexibility make it an ideal biotechnological platform for producing valuable chemicals, such as medium-chain-length polyhydroxyalkanoates (mcl-PHAs), which are considered the next generation bioplastics. This bacterium responds to environmental stimuli by rearranging its metabolism to improve its fitness and increase its chances of survival in harsh environments. Mcl-PHAs play an important role in central metabolism, serving as a reservoir of carbon and energy. Due to the complexity of mcl-PHAs’ metabolism, the manner in which P. putida changes its transcriptome to favor mcl-PHA synthesis in response to environmental stimuli remains unclear. Therefore, our objective was to investigate how the P. putida KT2440 wild type and mutants adjust their transcriptomes to synthesize mcl-PHAs in response to nitrogen limitation when supplied with sodium gluconate as an external carbon source. We found that, under nitrogen limitation, mcl-PHA accumulation is significantly lower in the mutant deficient in the stringent response than in the wild type or the rpoN mutant. Transcriptome analysis revealed that, under N-limiting conditions, 24 genes were downregulated and 21 were upregulated that were common to all three strains. Additionally, potential regulators of these genes were identified: the global anaerobic regulator (Anr, consisting of FnrA, Fnrb, and FnrC), NorR, NasT, the sigma54-dependent transcriptional regulator, and the dual component NtrB/NtrC regulator all appear to play important roles in transcriptome rearrangement under N-limiting conditions. The role of these regulators in mcl-PHA synthesis is discussed.


Author(s):  
Lev Levintov ◽  
Harish Vashisth

Ribonucleic acid (RNA) molecules are known to undergo conformational changes in response to various environmental stimuli including temperature, pH, and ligands. In particular, viral RNA molecules are a key example...


2014 ◽  
Vol 24 (7) ◽  
pp. 766-773 ◽  
Author(s):  
Violetta Pilorz ◽  
Peter S. Cunningham ◽  
Anthony Jackson ◽  
Alexander C. West ◽  
Travis T. Wager ◽  
...  

2017 ◽  
Vol 176 (6) ◽  
pp. R283-R308 ◽  
Author(s):  
Evanthia Diamanti-Kandarakis ◽  
Maurizio Dattilo ◽  
Djuro Macut ◽  
Leonidas Duntas ◽  
Efstathios S Gonos ◽  
...  

Aging and its underlying pathophysiological background has always attracted the attention of the scientific society. Defined as the gradual, time-dependent, heterogeneous decline of physiological functions, aging is orchestrated by a plethora of molecular mechanisms, which vividly interact to alter body homeostasis. The ability of an organism to adjust to these alterations, in conjunction with the dynamic effect of various environmental stimuli across lifespan, promotes longevity, frailty or disease. Endocrine function undergoes major changes during aging, as well. Specifically, alterations in hormonal networks and concomitant hormonal deficits/excess, augmented by poor sensitivity of tissues to their action, take place. As hypothalamic–pituitary unit is the central regulator of crucial body functions, these alterations can be translated in significant clinical sequelae that can impair the quality of life and promote frailty and disease. Delineating the hormonal signaling alterations that occur across lifespan and exploring possible remedial interventions could possibly help us improve the quality of life of the elderly and promote longevity.


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