Project description:Salinity strongly influences the physiology and distribution of nitrifying microorganisms, yet the effects of low salinity on these key players in nitrogen cycling remain understudied. This study investigates the impact of hypoosmolarity on different groups of ammonia oxidizers in soil and lake environments, as well as in pure culture isolates. In soil microcosms amended with ammonium, at low salinity levels (~120 µS/cm), which are comparable to values commonly found in pristine terrestrial and aquatic environments, the abundance of ammonia-oxidizing bacteria (AOB), dominated by Nitrosomonas oligotropha, significantly increased. In contrast, the growth of ammonia-oxidizing archaea (AOA), dominated by “Ca. Nitrosotenuis” of the Nitrosopumilaceae family, was stimulated by high salinity (~760 µS/cm). In ammonium-fed lake microcosms, the abundance of AOB, dominated by N. oligotropha, significantly increased under both low (~170 µS/cm) and high salinity (~850 µS/cm) conditions. In the presence of allylthiourea, a bacterial nitrification inhibitor, AOA were found to be sensitive to low salinity in both soil and lake microcosms. Consistently, pure culture studies revealed marked growth inhibition of AOA, especially of members of the Nitrosopumilaceae, under hypoosmolarity, unlike AOB and complete ammonia oxidizers (comammox) strains. Comparative genomic analyses with AOB and comammox, along with transcriptomic studies, suggested that the sensitivity of AOA to hypoosmolarity stress is attributed to a lack of sophisticated osmoregulatory transport systems and their S-layer cell wall structure. Overall, this study highlights the importance of hypoosmolarity as a key factor shaping the ecological niches and distribution of ammonia oxidizers as well as nitrification activities in terrestrial and aquatic environments increasingly affected in their salinities by intensified water cycles due to climate change.
Project description:Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, RP China
Hubei Key Laboratory of Metabolic and Chronic Diseases, Wuhan, RP China
Project description:Epigenetic variation has the potential to control environmentally dependent development and contribute to phenotypic responses to local environments. Environmental epigenetic studies of sexual organisms confirm the responsiveness of epigenetic variation, which should be even more important when genetic variation is lacking. A previous study of an asexual snail, Potamopyrgus antipodarum, demonstrated that different populations derived from a single clonal lineage differed in both shell phenotype and methylation signature when comparing lake versus river populations. Here, we examine methylation variation among lakes that differ in environmental disturbance and pollution histories. The differential DNA methylation regions (DMRs) identified among the different lake comparisons suggested a higher number of DMRs and variation between rural Lake 1 and one urban Lake 2 and between the two urban Lakes 2 and 3, but limited variation between the rural Lake 1 and urban Lake 3. DMR genomic characteristics and gene associations were investigated. Observations suggest there is no effect of geographic distance or any consistent pattern of DMRs between urban and rural lakes. Environmental factors may influence epigenetic response.
Project description:This study aims to provide a transcriptomics dataset for field grown rice plants subjected to mild drought concentrating on the two parents of a mapping population, Bala and Azucena. Plants were grown in 1.2 m2 plots under flooded conditions in Wuhan, China being sown on 2nd June 2007. Starting at 59 days after sowing, drought was imposed by withholding water, while a set of control plots had continued flooding conditions. The drought was imposed for 24 days during which time a small amount of water was added on 3 occasions to raise soil moisture to 30% by volume. After 24 days the second youngest fully expanded leaf was taken and gene expression analysis performed. We used microarrays to detail the global programme of gene expression underlying drought in rice plants with the aim of using the data to identify candidate genes for drought avoidance QTLs detected within the a rice mapping population. Two rice cultivars, Bala and Azucena, were grown in 1.2 m2 plots under flooded conditions in Wuhan, China being sown on 2nd June 2007. Starting at 59 days after sowing, drought was imposed by withholding water, while a set of control plots had continued flooding conditions. At 2 pm on the 83rd day after sowing (after 24 days of drought) the second youngest fully expanded leaf was taken off three plants in two plots per block, the leaves had the top and bottom 4 cm removed and the central portion of the leaf was placed in a bag and then into liquid N2. For the controls there was only one plot of the genotypes per block. There was one bag for each block and three replicate blocks. A total of 6 droughted leaf samples (3 Bala and 3 Azucena) and six control leaf samples (3 Bala and 3 Azucena) were collected for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, RP China
Hubei Key Laboratory of Metabolic and Chronic Diseases, Wuhan, RP China
Project description:To determine gene expression differences in the olfactory epithelium of sea lamprey between sequential yet behaviorally distinct adult life history stages 2 samples: parasitic adults removed from fish in northern Lake Huron and Lake Michigan in February and March, and reproductive adults collected from Lake Huron and Lake Michigan tributaries in June
Project description:To identify genes which were involved in histone deacetylation regulates lipid through H4K5 and H4K8. ChIP-seq and motif analysis of C. elegans which were fed with E. coli OP50 until reach to adult. After washing by M9 buffer for three times, worms were re-suspended in PBS, frozen immediately in liquid nitrogen for ChIP-seq which were carried out by Wuhan SeqHealth Tech Co.,Ltd (Wuhan, China). The chromatin was sheared into 0.2 to 1kb fragments then subjected to immunoprecipitation using antibodies for H4K5ac (Abcam, ab51997) or H4K8ac (Abcam ab45166). Indexed ChIP-seq libraries were prepared using the NEB Next Ultra DNA library prep kit (New England Biolabs) and pair-end sequences on iIIumina NovaSeq 6000. HOMER was used in motif analysis of deferentially enriched peaks 31.