In order to obtain salt-tolerant calli of Dandelion (Taraxacum officinale Weber), calli were induced from leaf explants of Dandelion on Murashige and Skoog's medium supplemented with 2.0 mg/L 6-benzyladenine and 0.5 mg/L 2,4-dichlorophen oxyacetic acid With 1.5% NaCl as selection pressure, most calli became brown and dead, whereas some new cell clusters appeared at the edge of the brown calli after 2 to 3 weeks. The survived cells were picked out and sub-cultured every 3 weeks onto the fresh selection medium and salt-tolerant calli were finally obtained through 4 continuous selections on the selection medium supplemented with 1.5% NaCl. Salt-tolerant calli increased steadily under a fixed NaCl stress though their relative growth rate decreased with increased NaCl concentration whereas the control calli which were sub-cultured by 4 continus selections on salt free medium ceased to grow under the same condition. This result indicated that the salt-tolerance of the selected calli is improved and this character is stable. Compared with the control, the SDS-PAGE pattern of the salt-tolerant calli had a unique 34 kD protein band. Its 30 kD and 18 kD protein bands were up-regulated. Further more, within the NaCl stress range up to 1.5%, the activities of antioxidant enzymes such as super oxidase dimutase, peroxidase and catalase, and the proline contents of the salt-tolerant calli were higher than those of the control. The results indicated that the selected calli with improved and stable salt tolerance were cell variants. The accumulation of the organic compatible solutes including proteins and the enhanced antioxidant capabilities in the salt tolerant calli are the two ways for them to regulate their osmotic homeostasis and alleviate the secondary reactive oxygen spexies damage respectively.
Adaptation, Physiological ; Cell Culture Techniques ; methods ; Drug Tolerance ; physiology ; Salt-Tolerant Plants ; genetics ; growth & development ; physiology ; Sodium Chloride ; pharmacology ; Stress, Physiological ; Taraxacum ; genetics ; growth & development ; physiology

PURPOSE: Plasma neurotrophin-3 (NT-3) levels are associated with several neural disorders. We previously reported that neurotrophins were released from salivary glands following acute immobilization stress. While the salivary glands were the source of plasma neurotrophins in that situation, the association between the expression of neurotrophins and the salivary gland under chronic stress conditions is not well understood. In the present study, we investigated whether NT-3 levels in the salivary gland and plasma were influenced by chronic stress. MATERIALS AND METHODS: Expressions of NT-3 mRNA and protein were characterized, using real-time polymerase chain reactions, enzyme-linked immunosorbent assay, and immunohistochemistry, in the submandibular glands of male rats exposed to chronic stress (12 h daily for 22 days). RESULTS: Plasma NT-3 levels were significantly increased by chronic stress (p<0.05), and remained elevated in bilaterally sialoadenectomized rats under the same condition. Since chronic stress increases plasma NT-3 levels in the sialoadenectomized rat model, plasma NT-3 levels were not exclusively dependent on salivary glands. CONCLUSION: While the salivary gland was identified in our previous study as the source of plasma neurotrophins during acute stress, the exposure to long-term stress likely affects a variety of organs capable of releasing NT-3 into the bloodstream. In addition, the elevation of plasma NT-3 levels may play important roles in homeostasis under stress conditions.
Animals ; Male ; Neurotrophin 3/*blood/genetics ; Rats ; Rats, Sprague-Dawley ; Stress, Physiological/*physiology ; Submandibular Gland/*metabolism

Autophagy is a conserved pathway for the bulk degradation of cytoplasmic components in all eukaryotes. This process plays a critical role in the adaptation of plants to drastic changing environmental stresses such as starvation, oxidative stress, drought, salt, and pathogen invasion. This paper summarizes the current knowledge about the mechanism and roles of plant autophagy in various plant stress responses.
Adaptation, Physiological ; Arabidopsis ; genetics ; physiology ; Arabidopsis Proteins ; genetics ; metabolism ; Autophagy ; genetics ; Disease Resistance ; Plant Diseases ; immunology ; Saccharomyces cerevisiae ; genetics ; Sequence Homology ; Stress, Physiological

In order to study the molecule mechanism of the differential expression in Dendrobium officinale under low temperature, the high cold resistance germplasms were used for constructing the RNA pools. SCoT markers were used to analyze the different cDNA pools transcribed from the RNA pools. 11 transcripts derived fragments from 500 cDNA amplified bands were amplified by 64 primers, and were sorted out, cloned, sequenced and analyzed. The results showed that cDNA pools with SCoT markers could be used for differential display in D. officinale under low temperature stress. Sequence analysis indicated that the transcripts derived fragments were significantly homologous in nucleotide sequence with membrane-associated proteins, osmotic regulation protein, CBF transcriptional factor, resistance protein. One left gene segments functions were still unknown, which may be related to the cold resistant gene expression in D. officinale.
Breeding ; Cold Temperature ; adverse effects ; Dendrobium ; genetics ; physiology ; Gene Expression Regulation, Plant ; Genetic Markers ; genetics ; Stress, Physiological ; genetics

Parkinson's disease (PD) is a common age-related neurodegenerative disorder characterized mainly by motor dysfunction resulting in bradykinesia, rigidity, tremor, gait impairment, and postural instability. The classic pathogenic feature of PD is preferential loss of dopaminergic neurons in the substantia nigra. Downregulation of rRNA transcription is one of major mechanisms to maintain cellular homeostasis under stress conditions. Nucleolar stress has emerged as a component of the degenerative process caused by impaired rRNA transcription and altered nucleolar integrity. Recent study has indicated that the response to stress conditions and quality control mechanisms are impaired in PD, and that metabolic stress may be a trigger mechanism for PD. This review aims to present evidence for a role of nucleolar stress in PD and has summarized mechanisms by which nucleolar stress may play a role in the progression of PD.
Cell Nucleolus ; physiology ; Humans ; Parkinson Disease ; etiology ; physiopathology ; RNA, Ribosomal ; genetics ; Signal Transduction ; Stress, Physiological ; TOR Serine-Threonine Kinases ; physiology

Metabolic engineering is a technologic platform for industrial strain improvement and aims not only at modifying microbial metabolic fluxes, but also improving the physiological performance of industrial microbes. Microbes will meet multiple stresses in industrial processes. Consequently, elicited gene responses might result in a decrease in overall cell fitness and the efficiency of biotransformation. Thus, it is crucial to develop robust and productive microbial strains that can be integrated into industrial-scale bioprocesses. In this review, we focus on the progress of these novel methods and strategies for engineering stress-tolerance phenotypes referring to rational metabolic engineering and inverse metabolic engineering in recent years. In addition, we also address problems existing in this area and future research needs of microbial physiological functionality engineering.
Bacteria ; genetics ; metabolism ; Bacterial Physiological Phenomena ; Biotechnology ; methods ; Fungi ; genetics ; metabolism ; physiology ; Industrial Microbiology ; methods ; Metabolic Engineering ; methods ; Metabolic Networks and Pathways ; Stress, Physiological

This study was aimed to investigate the effect of stress induced by high-intensity exercises on the cardiovascular system. In the epidemiological investigation, 200 subjects (test group) engaged in special high-intensity exercises, and 97 who lived and worked in the same environment and conditions as those in the test group, but did not participate in the exercises served as controls. In the second part of the study, 50 mice were randomly divided into control group, exhaustive swimming group, white noise group, exhaustive swimming plus white noise group, and pioglitazone intervention group. The results showed that the plasma concentrations of the myocardial injury markers heart fatty acid-binding protein (H-FABP), C-reactive protein (CRP), β-endorphin (β-EP) and levels of psychological stress were significantly increased in test group as compared with control group; special high-intensity exercises resulted in a significant elevation of the incidence of cardiac arrhythmias. Animal experiments showed that the plasma levels of corticosterone (CORT) and troponin I (TnI) were raised while the level of SOD was reduced in exhaustive swimming group, white noise group, and exhaustive swimming plus white noise group. The expression levels of PPARγ mRNA and protein were decreased in myocardial tissues in these groups as well. HE staining showed no remarkable change in myocardial tissues in all the groups. Treatment with pioglitazone significantly decreased the plasma levels of TnI and CORT, while increased the level of SOD and the expression levels of PPARγ mRNA and protein. It was concluded that the high-intensity exercises may induce a heavy physical and psychological stress and predispose the subjects to accumulated fatigue and sleep deprivation; high-intensity exercises also increases the incidence of arrhythmias and myocardial injury. PPARγ may be involved in the physical and psychological changes induced by high-intensity exercises.
Animals ; Heart Injuries ; physiopathology ; Male ; Mice ; PPAR gamma ; genetics ; physiology ; RNA, Messenger ; genetics ; Real-Time Polymerase Chain Reaction ; Stress, Physiological

Transgenic tobacco plants expressing a stress responsive gene BoRS1, isolated from Brassica oleracea var. acephala, under the control of the 35S promoter of the Cauliflower mosaic virus were produced. Some plants were further used to test the effect of high level BoRS1 expression on drought stress resistance. The presence of transgene in putative transgenic plants was confirmed by PCR analysis. Thirty-six among 130 transformants showed amplification of predicted fragment of BoRS1 while no amplification was observed in the control. Some transgenic lines confirmed by PCR analysis were analyzed through semi-quantitative one-step RT-PCR for the expression of BoRS1 gene. Amplification of 1.4 kb cDNA product revealed transcription of BoRS1 gene. Meanwhile, differential intensity of the cDNA band indicated variable expression levels of the transgene among different transformed lines. The water loss of detached leaves from the transgenic plants was slower than that of the control. Transgenic tobaccos and the non-transgenic controls were used for further drought stress experiments by using different concentration of mannitol. The transformants showed higher tolerance to drought stress than non-transgenic plants and different transgenic lines exhibited different tolerance during drought stress. These results showed that the BoRS1 gene probably play role in enhancing the ability to drought stress.
Adaptation, Physiological ; genetics ; Agrobacterium tumefaciens ; genetics ; Brassica ; genetics ; Dehydration ; Genes, Plant ; Plant Proteins ; genetics ; metabolism ; Plants, Genetically Modified ; genetics ; growth & development ; physiology ; Stress, Physiological ; Tobacco ; genetics ; growth & development ; physiology ; Transformation, Genetic ; Transgenes

In Candida albicans, adaptation to environmental pH is relevant to its pathogenicity. Calcium signaling pathway involves in many stress responses and often accompany with Ca2+ fluctuation. We constructed CCH1 and MID1 mutant strains and studied their effect on calcium influx and further investigated the regulation by Crz1p transcription factor. We used PCR-directed gene disruption to construct cch1delta/delta and mid1delta/delta null mutant. By using a flow cytometry-based method we monitored the free cytosolic Ca2+ levels under alkaline stress. Moreover, we constructed pPHO89-LacZ plasmids and by beta-Galactosidase assays, we analyzed the changes of LacZ activities after gene disruption. The results showed that alkaline stress induced calcium burst reduced obviously in cch1delta/delta and mid1delta/delta mutant strains, also for LacZ activities, and fully abolished in crz1delta/delta mutant strain. Finally, by realtime PCR, we confirmed the regulation role of Crz1p in CCH1 and MID1 genes but in a calcineurin independent way. Studies on the effect of calcium pathway on response to alkaline stress will provide an important theoretical basis for Candida albicans infection-oriented treatment and new drug targets.
Calcium Channels ; metabolism ; Candida albicans ; genetics ; metabolism ; physiology ; Fungal Proteins ; genetics ; physiology ; Gene Expression Regulation, Fungal ; Hydrogen-Ion Concentration ; Signal Transduction ; Stress, Physiological ; Transcription Factors ; metabolism ; physiology

Polyamine is an important physiological regulation substance functioning in a wide variety of biological processes, such as plant growth, development, senescence and adversity stress tolerance, which widely exist in all living organisms. Their biosynthetic pathways have already been revealed, and their physiological roles are being elucidated gradually. Previous work on polyamines biosynthetic deficiency mutants and various transgenic plants facilitates improved understanding of the important roles of polyamines and biosynthetic enzymes in plant growth and development. This paper summarizes researches in the biosynthetic pathways of polyamines in plants, focusing on research advances on functions of genes involved in polyamine metabolism. In addition, the potential research directions, especially the application of the genes in the genetic engineering of plant stress tolerance were also discussed.
Biosynthetic Pathways ; physiology ; Gene Expression Regulation, Plant ; Genes, Plant ; genetics ; Plant Physiological Phenomena ; Plants ; metabolism ; Plants, Genetically Modified ; Polyamines ; metabolism ; Stress, Physiological