Activating stress memory: eustressors as potential tools for plant breeding.

Plants are continuously exposed to stress conditions, such that they have developed sophisticated and elegant survival strategies, which are reflected in their phenotypic plasticity, priming capacity, and memory acquisition. Epigenetic mechanisms play a critical role in modulating gene expression and stress responses, allowing malleability, reversibility, stability, and heritability of favourable phenotypes to enhance plant performance. Considering the urgency to improve our agricultural system because of going impacting climate change, potential and sustainable strategies rely on the controlled use of eustressors, enhancing desired characteristics and yield and shaping stress tolerance in crops. However, for plant breeding purposes is necessary to focus on the use of eustressors capable of establishing stable epigenetic marks to generate a transgenerational memory to stimulate a priming state in plants to face the changing environment.

Potential application of yeasts from Ecuadorian chichas in controlled beer and chicha production.

The potential of yeasts isolated from traditional chichas as starter cultures, either for controlled production of the native beverage or for industrial beer production, has been investigated. Three S. cerevisiae strains and one T. delbrueckii strain isolated from four different Ecuadorian chichas were compared to ale and lager beer strains with respect to fermentation performance, sugar utilisation, phenolic off-flavour production, flocculation and growth at low temperature. Fermentations were performed in 15 °P all-malt wort and in a model chicha substrate at 12 °C and 20 °C. Tall-tube fermentations (1.5 L) were also performed with both substrates to assess yeast performance and beer quality. Among the strains tested, only one Ecuadorian S. cerevisiae strain was able to ferment the wort sugars maltose and maltotriose. Fermentations with all Ecuadorian strains were poor in wort at 12 °C relative to 20 °C, but were similar in model chicha substrate at both temperatures. The aromatic profile was different between species and strains. These results indicate the potential of yeasts derived from traditional Andean fermented beverages for commercial applications. One of the chicha strains demonstrated traits typical of domesticated brewery strains and could be suitable for ale fermentation, while the other strains may have potential for low-alcohol beer or chicha production.

Recommendations for the prevention and diagnosis of asthma in children: Evidence from international guidelines adapted for Mexico.

BACKGROUND: With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. METHODS: The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. RESULTS: The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference - all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6-11 years and ≥12 years. CONCLUSIONS: For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.

Biotechnological impact of stress response on wine yeast.

Wine yeast deals with many stress conditions during its biotechnological use. Biomass production and its dehydration produce major oxidative stress, while hyperosmotic shock, ethanol toxicity and starvation are relevant during grape juice fermentation. Most stress response mechanisms described in laboratory strains of Saccharomyces cerevisiae are useful for understanding the molecular machinery devoted to deal with harsh conditions during industrial wine yeast uses. However, the particularities of these strains themselves, and the media and conditions employed, need to be specifically looked at when studying protection mechanisms.

Efficacy and safety of D. pteronyssinus immunotherapy in local allergic rhinitis: a double-blind placebo-controlled clinical trial.

The effects of allergen immunotherapy (AIT) on local allergic rhinitis (LAR) are largely unknown. We conducted the first randomized, double-blind, placebo-controlled (DBPC), phase II trial of D. pteronyssinus (DP) subcutaneous AIT (DP-AIT) on LAR (clinicaltrials.gov identifier: NCT02123316). Thirty-six LAR patients received Pangramin PLUS DP or placebo for 24 months. The primary endpoints were symptoms, medication scores, and medication-free days. The secondary included skin test, serum specific IgE and IgG4, nasal allergen provocation test (NAPT), and adverse events. AIT-DP produced significant improvements in both primary and secondary endpoints vs placebo. After 12 months of AIT-DP, we detected a significant and marked increase in allergen tolerance with negative NAPT in 50% of patients, and significant increases of serum sIgG4. Immunotherapy was well tolerated; no systemic reactions were reported. This study demonstrated that AIT-DP is a safe and clinically effective treatment for LAR, confirming that LAR is a new indication for AIT.

Ovariectomy increases the age-induced hyperphosphorylation of Tau at hippocampal CA1.

One of the main hallmarks of Alzheimer's disease includes the neurofibrillary tangles formation produced by hyperphosphorylation of the Tau protein, whose expression is putatively regulated by the ovarian hormones estradiol and progesterone. Hippocampus is a brain region that participates in many functions related to learning and memory; in addition, it is abundant in both estradiol and progesterone receptors. In this study, we explore the expression of Tau hyperphosphorylation at hippocampus and the performance of rats in an autoshaping learning task at 5, 10 and 15 months after the ovaries removal. In these animals, ovariectomy was performed at 3 months of age. These data were compared with those derived from intact rats at 8, 13 and 18 months old. A clear decrease in the number of conditioned responses of both intact and ovariectomized rats in the autoshaping learning task was observed. The interaction of both factors confirms that, in this test, learning varies depending on aging and the presence or absence of ovaries. A progressive increase in hippocampal Tau phosphorylation at Ser-396 was observed in either intact or ovariectomized rats. Interestingly, an interaction between the analyzed factors shows that such hyperphosphorylation was potentiated by the absence of ovaries. These results emphasize the importance of aging and the lack of ovarian hormones for an associative learning test and for the expression of one of the most important hallmarks of Alzheimer's disease.

[Endometrial ablation with thermal balloon, experience in a private hospital]. / Ablación endometrial con balón térmico, experiencia en un hospital privado.

BACKGROUND: Traditionally, the treatment for menorrhagia includes pharmacological therapies (hormones and uterotonics) or surgical (dilatation/curettage and hysterectomy). Recently the FDA approved a non-invasive therapeutic option, known as endometrial ablation. Which it consists in a thermal balloon delivers (ThermaChoice y Thermablate EAS) which energy destroys the uterine lining, thus reducing the bleeding and even producing amenorrhea. And could offer other benefits such as reduction of the surgical time, and therefore: anesthesia time, postoperative complications and costs. Highlighting a greater patient satisfaction. OBJECTIVE: Describe the demographic characteristics, outcomes and patient satisfaction, which were treated with endometrial ablation for menorrhagia. MATERIAL AND METHODS: A descriptive, observational and retrospective study. During a period of 11 years (March 2012 to December 2013), in a private hospital, that includes 124 patients with menorrhagia, which were treated with endometrial ablation: 53 (43%) ThermaChoice y 71 (57%) Thermablate EAS. We used T Student and Fisher method to study the results. RESULTS: The 124 patients (100%) achieve all the criteria's of endometrial ablation according ACOG (American College of Obstetricians and Gynecologists) were candidates for. The mean age of our patients were 38 years old, who didn't respond to pharmacologic treatment had a definitive contraception. Among these women, 119 (96%) had a reduction in bleeding en the first 12 months, 25 (31%) presented with amenorrhea and 1 (<1%) required a surgical approach. Overall, 119 patients (96%) were satisfied with their results. CONCLUSIONS: Endometrial ablation is an approved FDA treatment for menorrhagia, which is safe, accessible and effective. With an easy implementation and low rate of complications.

[Peripartum cardiomyopathy: a case report]. / Miocardiopatía periparto: reporte de un caso.

Background: Peripartum cardiomyopathy also known as cardiomyopathy associated with pregnancy, is rarely a cause of heart failure, it affects pregnant or puerperal women in the first 5 months. Although the first case reported was in 1849, it was recognized until 1930. In 2010 the European Society of Cardiology Working Group on peripartum cardiomyopathy, defined this pathology as an idiopathic cardiomyopathy that affects pregnant women between the third trimester and five months after delivery. Characterized by a left ventricular failure with an ejection fraction of ≤45% and an end-diastolic dimension ≥2.7 cm/m2 , in absence of an identifiable cause of heart failure. Case report: We report a case of a 39-year-old patient, diagnosed with a peripartum cardiomyopathy in the early puerperium, characterized by hypertension, tachycardia, dyspnea and oxygen desaturation. The transesophageal echocardiogram reported heart failure, a hypokinetic left ventricle and a ventricular failure with an ejection fraction <40%. We could not identify an other cause to justify heart failure. Multidisciplinary management was administered successfully. Conclusion: The importance of this article relies in the fact that eripartum cardiomyopathy has a high morbidity and mortality. The impact of this pathology is unknow in our country. Here we establish and discuss the multidisciplinary management held in our hospital with this specific patient in order to improve the prognosis on future occasions.

Influence of age on IgE response in peanut-allergic children and adolescents from the Mediterranean area.

BACKGROUND: Peanut allergens are common triggers of food allergy. Analyses of sensitization patterns, relationships with other allergens, clinical symptoms, and variation with age are needed. We studied sensitization to Ara h 2, Ara h 9, and Pru p 3 in a peanut allergic children/adolescents and the relationship with peach and pollen. METHODS: Peanut allergic patients aged between 1 and 20 years old were classified into two groups: A) allergic to peanut only and B) allergic to peach and peanut. The IgE response was measured to Ara h 2, Ara h 9, and Pru p 3. RESULTS: Of 964 subjects evaluated, 28% were allergic to peanut. From this group, 68% were also sensitized to pollen. Urticaria was the most frequent entity followed by anaphylaxis and OAS. Fifty-eight percent had Ara h 2- and/or Ara h 9-specific IgE. More than half reported symptoms with peanut alone (Group A) and 35% to peanut and peach (Group B). We observed significant differences in sex, age, onset of symptoms, and sensitization to Artemisia between groups. IgE response to Ara h 2 was more frequent in Group A, and Ara h 9 and Pru p 3 in Group B. We observed a decrease in sensitization to Ara h 2 and an increase to Ara h 9 and Pru p 3 with increasing age. CONCLUSION: Peanut allergy is frequent in subjects with allergy to plant foods, with Ara h 2 and Ara h 9 being two important allergens. In younger patients, Ara h 2 predominates over Ara h 9. The reverse was observed in older patients.

Mitochondria inheritance is a key factor for tolerance to dehydration in wine yeast production.

UNLABELLED: Mitochondria are the cell's powerhouse when organisms are grown in the presence of oxygen. They are also the source of reactive oxygen species that cause damage to the biochemical components of the cell and lead to cellular ageing and death. Under winemaking conditions, Saccharomyces yeasts exclusively have a fermentative metabolism due to the high sugar content of grape must. However, their production as an active dry yeast (ADY) form required aerobic propagation and a dehydration process. In these industrial steps, oxidative stress is particularly harmful for the cell. In this work, we analysed the impact of the mitochondrial genome on oxidative stress response, longevity and dehydration tolerance using the synthetic interspecific hybrids obtained between two S. cerevisiae and S. uvarum strains. The isogenic nature of nuclear DNA of such hybrids allowed us to analyse the impact of mitochondrial DNA for fermentative and oxidative stress conditions. Under grape must conditions, the inheritance of mitochondrial DNA poorly impacted the fermentative performance of interspecific hybrids, unlike the hybrids with S. cerevisiae mitochondrial inheritance, which displayed increased tolerance to oxidative stress and dehydration, and showed an extended chronological longevity when cells were grown with aeration. SIGNIFICANCE AND IMPACT OF THE STUDY: In modern oenology, yeast starters are employed to inoculate grape juice, usually in the form of active dry yeast (ADY). The dehydration process implies stressful conditions that lead to oxidative damage. Other yeast species and interspecific hybrids other than Saccharomyces cerevisiae may be used to confer novel properties to the final product. However, these yeasts are usually more sensitive to drying. Understanding the causes of oxidative stress tolerance is therefore necessary for developing the use of these organisms in industry. This study indicates the impact of mitochondrial DNA inheritance for oxidative stress resistance in an interspecific context using isogenic Saccharomyces cerevisiae × Saccharomyces uvarum hybrids.

Basophil response to peanut allergens in Mediterranean peanut-allergic patients.

Ara h 1, Ara h 2, and Ara h 3 are important sensitizers in peanut allergy. Ara h 9 has also been shown to be relevant in the Mediterranean area. We evaluated the basophil response to peanut allergens and Pru p 3 in Mediterranean patients: Group 1, peanut and peach allergy; Group 2, peanut allergy and tolerance to peach; Group 3, peach allergy and tolerance to peanut; Group 4, nonallergic subjects that tolerate both peanut and peach. Compared to controls (Group 4), there was an increased basophil activation with Ara h 2 (P = 0.031) and Pru p 3 (P = 0.009) in Group 1 and with Ara h 1 (P = 0.016), Ara h 2 (P = 0.001), and Ara h 9 (P = 0.016) in Group 2. Importantly, only Ara h 2 showed an increased activation (P = 0.009) in Group 2 compared to Group 3. Ara h 2 is the best discriminating allergen for peanut allergy diagnosis in a Mediterranean population showing two patterns: patients also allergic to peach, responding to Ara h 2 and Pru p 3, and patients allergic only to peanut, responding to Ara h 1, Ara h 2, and Ara h 9.

Diagnosis of immediate hypersensitivity reactions to radiocontrast media.

BACKGROUND: No consensus exists on the diagnostic approach for immediate hypersensitivity reactions (IHR) to radiocontrast media (RCM). We analyzed the diagnostic value of a skin test (ST), drug provocation test (DPT) and basophil activation test (BAT) in patients with symptoms compatible with IHR to RCM. METHODS: Ninety patients with symptoms suggestive of IHR to RCM were evaluated. ST with a panel of RCM was performed, and if negative, DPT was carried out with the culprit RCM. If ST or DPT were positive, tolerance was assessed with an alternative RCM and BAT was carried out with the same panel used for ST. RESULTS: Eight (8.9%) cases were confirmed as having IHR, 5 (62.5%) by ST and 3 (37.5%) by DPT. Five from those confirmed as IHR (62.5%) had a positive BAT. CONCLUSIONS: Hypersensitivity to RCM was confirmed in 9%, by ST or DPT. BAT proved a valuable method for diagnosis.

Air quality assessment in biosphere reserves close to emission sources. The case of the Spanish "Tablas de Daimiel" national park.

This work shows that biosphere reserves, national parks and other protected natural areas require in situ tools to monitor and detect local and remote air pollution sources which are a threat to flora, fauna water and soil. Industries in surrounding areas, traffic and long-range transport of air pollution, can change with time and meteorology and so each national park should also have a historical database of the air quality in the site. This study reports surface measurements of ozone, NO, NO2, CO, SO2 and PM2.5 acquired from March 2020 to July 2021 in "Las Tablas de Daimiel", a wetland Mediterranean National Park bordered by different cities and new industries in the field of the revalorization of agricultural wastes. Simultaneous data from a background station in a rural area isolated from air pollution are considered as reference. Twelve campaigns of one week duration were also performed to sample air in sorbent tubes to analyse volatile organic compounds from anthropogenic sources. Data are discussed considering meteorology, especially wind speed and direction together with the assessment of back-trajectories of air masses from distant sources. The results show that the effects of pollution from local and faraway sources on air quality in the park were weak. Thus, except for the high levels of ozone, with a mean value of 71 µg.m-3, measured mass loadings for pollutants were low and not in exceedance of the air quality standards. Saharan dust events were frequent and contributed to PM2.5 levels in the site. NOx and SO2 average concentrations (3.2 and 0.4 µg.m-3, respectively) were below the recommended critical levels for vegetation and all the quantified VOCs were found in average concentration levels below 0.5 µg.m-3.

Immunoglobulin E-mediated hypersensitivity to amoxicillin: in vivo and in vitro comparative studies between an injectable therapeutic compound and a new commercial compound.

BACKGROUND: Skin testing with amoxicillin (AX) is necessary to diagnose immediate hypersensitivity reactions to this ß-lactam. A commercial AX (DIA-AX) has recently become available for skin testing. OBJECTIVE: The aim of this study was to compare DIA-AX with the injectable form (INJ-AX) in patients who have well-demonstrated IgE-mediated hypersensitivity to AX. METHODS: Chemical characterization using high-performance liquid chromatography of both DIA-AX and INJ-AX reagents was performed. Patients diagnosed with an immediate allergic reaction to AX and a positive skin test to INJ-AX (N=55) were re-evaluated within 6 months by performing skin testing with INJ-AX and DIA-AX. Basophil activation test (BAT) and Radioallergosorbent test (RAST) inhibition assay using both reagents were performed in a selected group of patients. RESULTS: The chemical analysis indicated that both DIA-AX and INJ-AX contained an AX compound with a purity above 95%. In the re-evaluation, 53 (96.4%) cases maintained skin test positivity to INJ-AX and were also positive to DIA-AX. Comparison of the papule area between the two reagents showed no significant differences between both reagents. BAT was performed in 30 samples and was positive to both compounds in 15 cases; no patient had a positive result to just one reagent. RAST inhibition studies using three individual cases and a pool of positive sera showed that the percentage inhibition detected with DIA-AX and INJ-AX was parallel and almost exactly the same. CONCLUSIONS: This study shows that DIA-AX is equivalent to INJ-AX in terms of skin test response, as well as with in vitro immunochemical and biological tests. DIA-AX can therefore be used in the diagnosis of immediate hypersensitivity reactions.

In vitro evaluation of IgE-mediated hypersensitivity reactions to quinolones.

BACKGROUND: Hypersensitivity IgE-mediated reactions to quinolones are not easy to diagnose, with skin testing inducing false positive results. The aim of the study was to evaluate the in vitro-specific IgE response in patients with immediate allergic reactions to quinolones. METHODS: We evaluated 38 patients with confirmed immediate allergic reactions to quinolones. Those with anaphylaxis were considered allergic by clinical history, once other possible causes were ruled out, and those with urticaria by drug provocation. Sepharose-radioimmunoassay (RIA) and basophil activation test (BAT) with ciprofloxacin, moxifloxacin and levofloxacin were performed. RESULTS: The quinolones involved were moxifloxacin (N = 24), ciprofloxacin (N = 11) and levofloxacin (N = 3). Sepharose-RIA was positive in 12 cases (31.57%) and BAT in 27 (71.05%). With Sepharose-RIA, 8 (21%) were positive to ciprofloxacin, 7 (18.4%) to moxifloxacin and 7 (18.4%) to levofloxacin. With BAT, 23 (60.5%) were positive to ciprofloxacin, 12 (31.6%) to moxifloxacin and 8 (21%) to levofloxacin. The specificity of the Sepharose-RIA was demonstrated by inhibition tests. To confirm that the BAT results observed were IgE mediated, the PI3K inhibitor wortmannin was used, with this compound inhibiting the BAT when stimulated with anti-IgE and the different quinolones, but not when fMLP was used as the basophil stimulator. Sepharose-RIA and BAT were repeated in positive cases 1 year later, detecting a decrease in all cases, with four becoming negative. CONCLUSION: Immediate hypersensitivity reactions to quinolones do occur, with moxifloxacin being the drug most frequently involved. The BAT is a useful method for diagnosing patients. Specific IgE was demonstrated by Sepharose-RIA and inhibition assay.

Probable interaction between trazodone and carbamazepine.

The need to maintain long-term treatment of chronic pathologies makes the appearance of interactions possible when such therapies incorporate other drugs to deal with the aggravation of the same or other intercurrent pathologies. A case is presented in which the addition of trazodone to a chronic treatment with carbamazepine (CBZ) is associated with symptoms typical for intoxication by this antiepileptic, accompanied by a raised serum concentration. When the trazodone was suspended, these symptoms lessened and the concentration of CBZ decreased progressively, suggesting a probable interaction between the 2 drugs.

Impact of SARS-CoV-2 lockdown and de-escalation on air-quality parameters.

The SARS-CoV-2 health crisis has temporarily forced the lockdown of entire countries. This work reports the short-term effects on air quality of such unprecedented paralysis of industry and transport in different continental cities in Spain, one of the countries most affected by the virus and with the hardest confinement measures. The study takes into account sites with different sizes and diverse emission sources, such as traffic, residential or industrial emissions. This work reports new field measurement data for the studied pandemic period and assesses the air quality parameters within the historic trend of each pollutant and site. Thus, 2013-2020 data series from ground-air quality monitoring networks have been analysed to find out statistically significant changes in atmospheric pollutants during March-June 2020 due to this sudden paralysis of activity. The results show substantial concentration drops of primary pollutants, including NOx, CO, BTX, NMHC and NH3. Particulate matter changes were smaller due to the existence of other natural sources. During the lockdown the ozone patterns were different for each studied location, depending on the VOCs-NOx ratios, with concentration changes close to those expected from the historical series in each site and not statistically attributable to the health crisis effects. Finally, the gradual de-escalation and progressive increase of traffic density within cities reflects a slow recovery of primary pollutants. The results and conclusions for these cities, with different sizes and population, and specific emission sources, may serve as a behavioural model for other continental sites and help understand future crises.

Natural killer-dendritic cell interaction in lymphocyte responses in hypersensitivity reactions to betalactams.

BACKGROUND: Betalactams are the commonest cause of allergic reactions mediated by either IgE or T lymphocytes in which innate and adaptive immune systems mediate the earlier stages of immunological responses. One of the links between these systems is related to the interaction between natural killer (NK) and dendritic cells (DC). We have evaluated the role of NK cells and NK-DC interaction in the immunopathological mechanisms of nonimmediate reactions to betalactams. METHODS: Patients allergic to amoxicillin (AX) (N = 17) and tolerant controls (N = 13) were included. Changes in phenotype (CD69, IFNγ, perforin, and granzyme B) in AX-stimulated NK cells, the cytotoxic activity on mature or immature DC (imDC), and the proliferation and phenotype of NK lymphocytes after culture with AX and DC were determined by flow cytometry. RESULTS: Amoxicillin induced activation and increases of perforin and granzyme B (P = 0.007 and P = 0.041 respectively) but not IFNγ production in NK cells from patients. In NK subpopulations, AX induced a significant enhancement of perforin and granzyme B in CD56(dim) (P = 0.005 and P = 0.002 respectively) and of IFNγ in CD56(bright) (P = 0.001). The cytotoxic phenotype was demonstrated by an increase of annexin V only in imDC (P < 0.001). Amoxicillin also induced an increased NK proliferation with different patterns, cytotoxic or proinflammatory, depending on the presence of imDC or mature DC, respectively. No differences were observed in NK cells from tolerant controls. CONCLUSION: These data could demonstrate the involvement of NK cells in the immunopathological mechanisms of nonimmediate allergic reactions to AX, showing that both the innate and adaptive immune systems are involved and crosstalk, producing amplification of the harmful effects observed in these drug reactions.

IgE-mediated hypersensitivity reactions to methylprednisolone.

BACKGROUND: Allergic reactions to systemically administered corticosteroids seem to be infrequent considering their extensive use. The aim of the study was to evaluate the IgE response in patients with immediate allergic reactions to methylprednisolone (MP). METHODS: Four subjects who developed immediate reactions after MP administration and ten controls with good tolerance to MP administration were evaluated. Skin prick and intradermal testing were done using MP, hydrocortisone (HC), and dexamethasone (DX). If negative, a drug provocation test (DPT) was done to confirm the diagnosis and assess cross-reactivity. The in vitro IgE response was evaluated by the basophil activation test (BAT) and ImmunoCAP. RESULTS: Three patients were diagnosed by the presence of a positive skin test in the immediate reading with MP, two by prick and one by intradermal testing, and one patient was skin test negative and diagnosed by DPT. All four patients had good tolerance to HC and DX. The BAT was positive for just MP in those patients with positive skin tests, with all patients being negative for HC and DX. Two patients were also ImmunoCAP positive to MP. CONCLUSIONS: This study confirms the existence of immediate allergic reactions to MP and that some are mediated by specific IgE antibodies. Skin testing, ImmunoCAP and the BAT are useful to confirm the diagnosis.

Ubiquitin ligase Rsp5p is involved in the gene expression changes during nutrient limitation in Saccharomyces cerevisiae.

Rsp5p is an essential ubiquitin ligase involved in many different cellular events, including amino acid transporters degradation, transcription initiation and mRNA export. It plays important role in both stress resistance and adaptation to the change of nutrients. We have found that ubiquitination machinery is necessary for the correct induction of the stress response SPI1 gene at the entry of the stationary phase. SPI1 is a gene whose expression is regulated by the nutritional status of the cell and whose deletion causes hypersensitivity to various stresses, such as heat shock, alkaline stress and oxidative stress. Its regulation is mastered by Rsp5p, as mutations in this gene lead to a lower SPI1 expression. In this process, Rsp5p is helped by several proteins, such as Rsp5p-interacting proteins Bul1p/2p, the ubiquitin conjugating protein Ubc1p and ubiquitin proteases Ubp4p and Ubp16p. Moreover, a mutation in the RSP5 gene has a global effect at the gene expression level when cells enter the stationary phase. Rsp5p particularly controls the levels of the ribosomal proteins mRNAs at this stage. Rsp5p is also necessary for a correct induction of p-bodies under stress conditions, indicating that this protein plays an important role in the post-transcriptional fate of mRNA under nutrient starvation.