ABSTRACT
SUN gene is a group of key genes regulating plant growth and development. Here, SUN gene families of strawberry were identified from the genome of the diploid Fragaria vesca, and their physicochemical properties, genes structure, evolution and genes expression were also analyzed. Our results showed that there were thirty-one FvSUN genes in F. vesca and the FvSUNs encoded proteins were classified into seven groups, and the members in the same group showed high similarity in gene structures and conservative motifs. The electronic subcellular localization of FvSUNs was mainly in the nucleus. Collinearity analysis showed that the members of FvSUN gene family were mainly expanded by segmental duplication in F. vesca, and Arabidopsis and F. vesca shared twenty-three pairs of orthologous SUN genes. According to the expression pattern in different tissues shown by the transcriptome data of F. vesca, the FvSUNs gene can be divided into three types: (1) expressed in nearly all tissues, (2) hardly expressed in any tissues, and (3) expressed in special tissues. The gene expression pattern of FvSUNs was further verified by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, the seedlings of F. vesca were treated by different abiotic stresses, and the expression level of 31 FvSUNs genes were assayed by qRT-PCR. The expression of most of the tested genes was induced by cold, high salt or drought stress. Our studies may facilitate revealing the biological function and molecular mechanism of SUN genes in strawberry.
Subject(s)
Fragaria/metabolism , Genes, Plant , Stress, Physiological/genetics , Arabidopsis/genetics , Plant Development , Gene Expression Regulation, Plant , Plant Proteins/metabolismABSTRACT
Under nutritional stress, cells undergo metabolic rewiring that results in changes of various cellular processesthat include gene transcription. This transcriptional regulation requires dynamic chromatin remodeling thatinvolves histone post-translational modifications. There are several histone marks that may act as switchesupon starvation for stress-response pathways.
ABSTRACT
Objective: We examined associations of different adipositymeasures with cortisol responses during the Trier Social StressTest for children (TSST-C).Design: Descriptive study.Setting: Holdsworth Memorial Hospital, Mysore, India.Participants: Adolescents aged 13.5y from a birth cohort wererecruited (N=269, 133 boys).Methods: The stressor (TSST-C) was 5-minutes each of publicspeaking and mental arithmetic tasks in front of two unfamiliar‘judges’. Salivary cortisol concentrations were measured atbaseline and at regular intervals after TSST-C. Weight, height,sub scapular and triceps skinfold thickness, and waist and hipcircumference were measured, and percentage body fat wasestimated (fat%; bioimpedance). Body mass index (BMI) andWaist-to-hip ratio (WHR) were calculated. All variables wereconverted into within-cohort SD scores before analysis. Stress-induced change in cortisol concentrations from baseline (cortisolresponse) was examined in relation to adiposity.Results: Stress increased cortisol concentrations significantlyfrom baseline (mean (SD): 5.5 (6.4) ng/mL; P<0.001). HigherWHR was associated with lower cortisol response at 20 and 30-minutes after stress (~0.13 SD decrease in cortisol response perSD higher WHR, P<0.05). Higher fat% was also associated withlower cortisol response only in girls 20-minutes post-stress (0.23SD lower response per SD higher fat%, P=0.004). Sum of skinfoldthickness and BMI were not associated with cortisol responses.Conclusions: Abdominal adiposity is associated with reducedhypothalamic-pituitary-adrenal axis reactivity to stress in thisadolescent population.
ABSTRACT
Cryptococcus neoformans is a basidiomycete human fungal pathogen that causes meningoencephalitis in both immunocompromised and immunocompetent individuals. The ability to sense and respond to diverse extracellular signals is essential for the pathogen to infect and cause disease in the host. Four major stress-activated signaling (SAS) pathways have been characterized in C. neoformans, including the HOG (high osmolarity glycerol response), PKC/Mpk1 MAPK (mitogen-activated protein kinase), calcium-dependent calcineurin, and RAS signaling pathways. The HOG pathway in C. neoformans not only controls responses to diverse environmental stresses, including osmotic shock, UV irradiation, oxidative stress, heavy metal stress, antifungal drugs, toxic metabolites, and high temperature, but also regulates ergosterol biosynthesis. The PKC (Protein kinase C)/Mpk1 pathway in C. neoformans is involved in a variety of stress responses, including osmotic, oxidative, and nitrosative stresses and breaches of cell wall integrity. The Ca2+/calmodulin- and Ras-signaling pathways also play critical roles in adaptation to certain environmental stresses, such as high temperature and sexual differentiation. Perturbation of the SAS pathways not only impairs the ability of C. neoformans to resist a variety of environmental stresses during host infection, but also affects production of virulence factors, such as capsule and melanin. A drug(s) capable of targeting signaling components of the SAS pathway will be effective for treatment of cryptococcosis.