Project description:The on-going Microbial Observatory Experiments on the International Space Station (ISS) revealed the presence of various microorganisms that may be affected by the distinct environment of the ISS. The low-nutrient environment combined with enhanced irradiation and microgravity may trigger changes in the molecular suit of microorganisms leading to increased virulence and resistance of microbes. Proteomic characterization of two Aspergillus fumigatus strains, ISSFT-021 and IF1SW-F4, isolated from HEPA filter debris and cupola surface of the ISS, respectively, is presented, along with a comparison to experimentally established clinical isolates Af293 and CEA10. In-depth analysis highlights variations in the proteome of both ISS-isolated strains when compared to the clinical strains. Proteins up-regulated in ISS isolates were involved in oxidative stress response, and carbohydrate and secondary metabolism. This report provides insight into possible molecular adaptation of filamentous fungi to the unique ISS environment. Lastly, an attempt was made to elucidate plausible causes of the enhanced virulence of both ISS-isolated A. fumigatus strains.
Project description:This study presents the first global genomic, proteomic, and secondary metabolomic characterization of the filamentous fungus, Aspergillus nidulans, following growth on the International Space Station (ISS). The investigation included the A. nidulans wild-type and 3 mutant strains, two of which were genetically engineered to enhance secondary metabolite (SM) production. Whole genome sequencing (WGS) revealed that ISS conditions altered the A. nidulans genome in specific regions. In strain CW12001, which features overexpression of the SM global regulator laeA, ISS conditions induced a point mutation that resulted in the loss of the laeA stop codon. Differential expression of proteins involved in stress response, carbohydrate metabolic processes, and SM biosynthesis was observed. ISS conditions significantly decreased prenyl xanthone production in the wild-type strain and increased asperthecin production in LO1362 and CW12001, which are deficient in a major DNA repair mechanism. Together, these data provide valuable insights into the genetic and molecular adaptation mechanism of A. nidulans to the spacecraft environment and present many economic benefits.
Project description:Nuclear-localized RNA binding proteins are involved in various aspects of RNA metabolism, which in turn modulates gene expression. However, the functions of nuclear-localized RNA binding proteins in plants are poorly understood. Here we report the functions of two proteins containing RNA recognition motifs, At RZ-1B and At RZ-1C, in Arabidopsis. At RZ-1B and At RZ-1C were localized to nuclear speckles and interacted with a spectrum of serine/arginine-rich (SR) proteins through their C-termini. At RZ-1C preferentially bound to purine-rich RNA sequences in vitro through its N-terminal RNA recognition motif. Disrupting the RNA-binding activity of At RZ-1C with SR proteins through over-expression of the C-terminus of At RZ-1C conferred defective phenotypes similar to those observed in At rz-1b/At rz-1c double mutants, including delayed seed germination, reduced stature, and serrated leaves. Loss of function of At RZ-1B and At RZ-1C was accompanied by defective splicing of many genes and global perturbation of gene expression. In addition, we found that At RZ-1C directly targeted FLC, promoting efficient splicing of FLC introns and likely also repressing FLC transcription. Our findings highlight the critical role of At RZ-1B/1C in regulating RNA splicing, gene expression, and many key aspects of plant development via interaction with proteins including SR proteins.
Project description:SREBF-1c is a transcription factor regulating fatty acid biosynthesis. We have charaterized the impact of the abcence of SREBF-1c on the development of peripheral neuropathy In this dataset we included expression data from dissected sciatic nerve from 10 months old SREBF-1c KO mice and relative littermates.
Project description:Nuclear-localized RNA binding proteins are involved in various aspects of RNA metabolism, which in turn modulates gene expression. However, the functions of nuclear-localized RNA binding proteins in plants are poorly understood. Here we report the functions of two proteins containing RNA recognition motifs, At RZ-1B and At RZ-1C, in Arabidopsis. At RZ-1B and At RZ-1C were localized to nuclear speckles and interacted with a spectrum of serine/arginine-rich (SR) proteins through their C-termini. At RZ-1C preferentially bound to purine-rich RNA sequences in vitro through its N-terminal RNA recognition motif. Disrupting the RNA-binding activity of At RZ-1C with SR proteins through over-expression of the C-terminus of At RZ-1C conferred defective phenotypes similar to those observed in At rz-1b/At rz-1c double mutants, including delayed seed germination, reduced stature, and serrated leaves. Loss of function of At RZ-1B and At RZ-1C was accompanied by defective splicing of many genes and global perturbation of gene expression. In addition, we found that At RZ-1C directly targeted FLC, promoting efficient splicing of FLC introns and likely also repressing FLC transcription. Our findings highlight the critical role of At RZ-1B/1C in regulating RNA splicing, gene expression, and many key aspects of plant development via interaction with proteins including SR proteins. mRNA-seq to look at the transcriptome and splicing differences between wild type and At rz-1b At rz-1c mutant of Arabidopsis thaliana
Project description:SHOX mutations and deletions of the downstream regulatory region have been reported in cases with idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD). Recently, a deletion and duplication of upstream enhancers have been described in ISS. Here, we aimed to evaluate the contribution of upstream copy number variations (CNVs) to the pathogenesis of ISS, to validate the enhancer role of the upstream enhancers in human cells, and to characterize the chromatin architecture of the cis-regulatory landscape of SHOX. CNV analysis of three upstream conserved non-coding elements (CNEs), CNE-5, CNE-3 and CNE-2, in 501 ISS referrals with no established molecular diagnosis revealed two deletions and one duplication. Enhancer activity of the upstream CNEs was corroborated by luciferase assays in human osteosarcoma U2OS cells. In addition, all three CNEs overlap with reported H3K27ac ChIP-seq marks in human embryonic limb buds. To characterize the chromatin interaction profile of the SHOX region, chromosome conformation capture (4C-seq) was performed in chicken embryo limb buds and in U2OS cells, revealing interactions of the upstream CNEs with the SHOX promoter. Moreover, the 4C-seq interaction maps and H3K27ac marks indicated that the cis-regulatory landscape of SHOX encompasses 1 Mb, suggesting additional cis-regulatory elements controlling SHOX.In conclusion, we showed that upstream CNVs of SHOX are rare in ISS and have incomplete penetrance. Chromatin interaction maps, luciferase assays and H3K27ac marks further support an enhancer function for the upstream CNEs. Finally, we demonstrated that the cis-regulatory landscape of SHOX is larger than previously anticipated potentially harboring novel cis-regulatory elements, which may be involved in the pathogenesis of molecularly unsolved ISS cases..