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1.
Int J Adv Manuf Technol ; 101(1-4): 391-417, 2019 Mar 17.
Article in English | MEDLINE | ID: mdl-32454552

ABSTRACT

In 2014, NASA, in partnership with Made In Space, Inc., launched the first 3D printer to the International Space Station. Results of the first phase of operations for this mission demonstrated use of the fused filament fabrication (FFF) process for 3D printing in a microgravity environment. Previously published results indicated differences in density and mechanical properties of specimens printed in microgravity and those manufactured with the printer prior to its launch to ISS. Based on extensive analyses, these differences were hypothesized to be a result of subtle changes in manufacturing process settings rather than a microgravity influence on the FFF process. Phase II operations provided an opportunity to produce additional specimens in microgravity, evaluate the impact of changes in the extruder standoff distance, and ultimate provide a more rigorous assessment of microgravity effects through control of manufacturing process settings. Based on phase II results and a holistic consideration of phase I and phase II flight specimens, no engineering-significant microgravity effects on the process are noted. Results of accompanying material modeling efforts, which simulate the FFF process under a variety of conditions (including microgravity), are also presented. No significant microgravity effects on material outcomes are noted in the physics-based model of the FFF process. The 3D printing in zero G technology demonstration mission represents the first instance of off-world manufacturing. It represents the first step toward transforming logistics for long duration space exploration and is also an important crew safety enhancement for extended space missions where cargo resupply is not readily available. This paper presents the holistic results of phase I and II on-orbit operations and also includes material modeling efforts.

2.
Nucleic Acids Res ; 43(1): 115-28, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25477386

ABSTRACT

It was recently reported that the sizes of many mRNAs change when budding yeast cells exit mitosis and enter the meiotic differentiation pathway. These differences were attributed to length variations of their untranslated regions. The function of UTRs in protein translation is well established. However, the mechanism controlling the expression of distinct transcript isoforms during mitotic growth and meiotic development is unknown. In this study, we order developmentally regulated transcript isoforms according to their expression at specific stages during meiosis and gametogenesis, as compared to vegetative growth and starvation. We employ regulatory motif prediction, in vivo protein-DNA binding assays, genetic analyses and monitoring of epigenetic amino acid modification patterns to identify a novel role for Rpd3 and Ume6, two components of a histone deacetylase complex already known to repress early meiosis-specific genes in dividing cells, in mitotic repression of meiosis-specific transcript isoforms. Our findings classify developmental stage-specific early, middle and late meiotic transcript isoforms, and they point to a novel HDAC-dependent control mechanism for flexible transcript architecture during cell growth and differentiation. Since Rpd3 is highly conserved and ubiquitously expressed in many tissues, our results are likely relevant for development and disease in higher eukaryotes.


Subject(s)
Gene Expression Regulation, Developmental , Histone Deacetylases/metabolism , Meiosis/genetics , Mitosis/genetics , RNA Isoforms/metabolism , Repressor Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Mutation , Nucleotide Motifs , Promoter Regions, Genetic , Protein Subunits/metabolism , RNA Isoforms/genetics , RNA Polymerase II/metabolism , Saccharomyces cerevisiae Proteins/genetics , Transcription Initiation Site , Untranslated Regions , Vesicular Transport Proteins/genetics , mRNA Cleavage and Polyadenylation Factors/genetics , tRNA Methyltransferases
3.
J Proteome Res ; 8(7): 3689-92, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19344107

ABSTRACT

Policies supporting the rapid and open sharing of genomic data have directly fueled the accelerated pace of discovery in large-scale genomics research. The proteomics community is starting to implement analogous policies and infrastructure for making large-scale proteomics data widely available on a precompetitive basis. On August 14, 2008, the National Cancer Institute (NCI) convened the "International Summit on Proteomics Data Release and Sharing Policy" in Amsterdam, The Netherlands, to identify and address potential roadblocks to rapid and open access to data. The six principles agreed upon by key stakeholders at the summit addressed issues surrounding (1) timing, (2) comprehensiveness, (3) format, (4) deposition to repositories, (5) quality metrics, and (6) responsibility for proteomics data release. This summit report explores various approaches to develop a framework of data release and sharing principles that will most effectively fulfill the needs of the funding agencies and the research community.


Subject(s)
Access to Information , Proteomics/methods , Proteomics/standards , Congresses as Topic , Cooperative Behavior , Data Collection , Genomics , Humans , Information Dissemination , Proteome , Public Policy , Research
4.
Mol Cell ; 21(3): 319-30, 2006 Feb 03.
Article in English | MEDLINE | ID: mdl-16455487

ABSTRACT

Many disease states result from gene overexpression, often in a specific genetic context. To explore gene overexpression phenotypes systematically, we assembled an array of 5280 yeast strains, each containing an inducible copy of an S. cerevisiae gene, covering >80% of the genome. Approximately 15% of the overexpressed genes (769) reduced growth rate. This gene set was enriched for cell cycle-regulated genes, signaling molecules, and transcription factors. Overexpression of most toxic genes resulted in phenotypes different from known deletion mutant phenotypes, suggesting that overexpression phenotypes usually reflect a specific regulatory imbalance rather than disruption of protein complex stoichiometry. Global overexpression effects were also assayed in the context of a cyclin-dependent kinase mutant (pho85Delta). The resultant gene set was enriched for Pho85p targets and identified the yeast calcineurin-responsive transcription factor Crz1p as a substrate. Large-scale application of this approach should provide a strategy for identifying target molecules regulated by specific signaling pathways.


Subject(s)
Gene Expression Regulation, Fungal , Genes, Fungal , Phenotype , Signal Transduction/physiology , Gene Expression Profiling , Oligonucleotide Array Sequence Analysis , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism
5.
Nat Genet ; 34(1): 35-41, 2003 May.
Article in English | MEDLINE | ID: mdl-12679813

ABSTRACT

To verify the genome annotation and to create a resource to functionally characterize the proteome, we attempted to Gateway-clone all predicted protein-encoding open reading frames (ORFs), or the 'ORFeome,' of Caenorhabditis elegans. We successfully cloned approximately 12,000 ORFs (ORFeome 1.1), of which roughly 4,000 correspond to genes that are untouched by any cDNA or expressed-sequence tag (EST). More than 50% of predicted genes needed corrections in their intron-exon structures. Notably, approximately 11,000 C. elegans proteins can now be expressed under many conditions and characterized using various high-throughput strategies, including large-scale interactome mapping. We suggest that similar ORFeome projects will be valuable for other organisms, including humans.


Subject(s)
Caenorhabditis elegans/genetics , Genome , Alternative Splicing , Animals , Cloning, Molecular , DNA, Complementary/genetics , DNA, Helminth/genetics , Databases, Genetic , Exons , Expressed Sequence Tags , Gene Expression , Genes, Helminth , Genomics , Helminth Proteins/genetics , Humans , Introns , Open Reading Frames , Proteome , Proteomics
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