Candida albicans response to spaceflight (NASA STS-115) --- GSM1231690_Slide_43

  • albicans
  • candida

Candida albicans response to spaceflight (NASA STS-115) --- GSM1231690_Slide_43

This study presents the first global transcriptional profiling and phenotypic characterization of the major human opportunistic fungal pathogen, Candida albicans, grown in spaceflight conditions. Microarray analysis revealed that C. albicans subjected to short-term spaceflight culture differentially regulated 454 genes compared to synchronous ground controls, which represented 8.4% of the analyzed ORFs. Spaceflight-cultured C. albicans induced genes involved in cell aggregation (similar to flocculation), which was validated by microscopic and flow cytometry analysis. We also observed enhanced random budding of spaceflight-cultured cells as opposed to more normal bipolar budding patterns for ground samples, in accordance with the gene expression data. Furthermore, genes involved in antifungal agent and stress resistance were differentially regulated in spaceflight, including induction of ABC transporters and members of the major facilitator family, downregulation of ergosterol-encoding genes, and upregulation of genes involved in oxidative stress resistance. Finally, downregulation of genes involved in the actin cytoskeleton was observed. Interestingly, the transcriptional regulator Cap1 and over 30% of the Cap1 regulon was differentially expressed in spaceflight-cultured C. albicans. A potential role for Cap1 in the spaceflight response of C. albicans is suggested, as this regulator is involved in random budding, cell aggregation, actin cytoskeleton, and oxidative stress resistance; all related to observed spaceflight-associated changes of C. albicans. While culture of C. albicans in microgravity potentiates a global change in gene expression that could induce a virulence-related phenotype, no increased virulence in a murine intraperitoneal (i.p.) infection model was observed. This study represents an important basis for the assessment of the risk that commensal flora could play during spaceflight missions. Furthermore, since the low fluid-shear environment of microgravity is relevant to physical forces encountered by pathogens during the infection process, insights gained from this study could identify novel infectious disease mechanisms, with downstream benefits for the general public. Cells were grown for 24 hours on the space shuttle or as ground-based controls, preserved in RNALater, and stored at -80C. Four samples of each flight- and ground-based controls were harvested for microarray analysis. GAP is Group Activation Pack and each GAP contains 8 FPAs. The numbers represent the # assigned to the particular GAP and the number assigned to the specific FPA (1-8) within the indicated GAP. The same hardware is used for the flight samples and the ground samples.


NameSocrata field nameColumn name in sgr mountData typeDescription
Spot Rowspot_rowspot_rowText
Ch2 N Rgn Ratioch2_n_rgn_ratioch2_n_rgn_ratioNumber
Ch2 N Median of Ratiosch2_n_median_of_ratiosch2_n_median_of_ratiosNumber
Ch2 N Ratio of Mediansch2_n_ratio_of_mediansch2_n_ratio_of_mediansNumber
Ch2 N Log Ratioch2_n_log_ratioch2_n_log_ratioNumber
Ch2 N Ratio of Meansch2_n_ratio_of_meansch2_n_ratio_of_meansNumber
Ch1 N Medianch1_n_medianch1_n_medianNumber
Sum of Meanssum_of_meanssum_of_meansNumber
Ch2 Log Ratioch2_log_ratioch2_log_ratioNumber
Ch1 N Meanch1_n_meanch1_n_meanNumber
Sum of Medianssum_of_medianssum_of_mediansNumber
Ch2 Rgn R²ch2_rgn_rch2_rgn_rNumber
Ch2 Ratio of Meansch2_ratio_of_meansch2_ratio_of_meansNumber
Ch2 N (Mean-B)ch2_n_mean_bch2_n_mean_bNumber
Ch2 N Meanch2_n_meanch2_n_meanNumber
Ch2 N (Median-B)ch2_n_median_bch2_n_median_bNumber
Ch1 N (Mean-B)ch1_n_mean_bch1_n_mean_bNumber
Ch2 N Medianch2_n_medianch2_n_medianNumber
Ch2 Median of Ratiosch2_median_of_ratiosch2_median_of_ratiosNumber
Ch2 Rgn Ratioch2_rgn_ratioch2_rgn_ratioNumber
Ch2 F % Sat.ch2_f_satch2_f_satNumber
Ch2 SDch2_sdch2_sdNumber
Ch2 Meanch2_meanch2_meanNumber
Ch2 B Meanch2_b_meanch2_b_meanNumber
Ch2 B Medianch2_b_medianch2_b_medianNumber
Ch1 Mean - Bch1_mean_bch1_mean_bNumber
Ch1 Median - Bch1_median_bch1_median_bNumber
Ch2 Medianch2_medianch2_medianNumber
Ch1 SignalNoiseRatioch1_signalnoiseratioch1_signalnoiseratioNumber
Ch2 Mean - Bch2_mean_bch2_mean_bNumber
Ch2 Ratio of Mediansch2_ratio_of_mediansch2_ratio_of_mediansNumber
Ch2 B SDch2_b_sdch2_b_sdNumber
Ch1 B SDch1_b_sdch1_b_sdNumber
Ch1 % > B + 1 SDch1_b_1_sdch1_b_1_sdNumber
Ch1 % > B + 2 SDch1_b_2_sdch1_b_2_sdNumber
Ch1 F % Sat.ch1_f_satch1_f_satNumber
Ch1 Meanch1_meanch1_meanNumber
Ch1 B Meanch1_b_meanch1_b_meanNumber
B Pixelsb_pixelsb_pixelsNumber
Ch1 Medianch1_medianch1_medianNumber
Ch1 SDch1_sdch1_sdNumber
Ch1 B Medianch1_b_medianch1_b_medianNumber
F Pixelsf_pixelsf_pixelsNumber
Array Rowarray_rowarray_rowText
Spot Columnspot_columnspot_columnText
Ch2 Mean of Ratiosch2_mean_of_ratiosch2_mean_of_ratiosNumber
Ch2 Ratios SDch2_ratios_sdch2_ratios_sdNumber
Ch1 N (Median-B)ch1_n_median_bch1_n_median_bNumber
Ch2 N Mean of Ratiosch2_n_mean_of_ratiosch2_n_mean_of_ratiosNumber
Array Columnarray_columnarray_columnText
Ch2 Median - Bch2_median_bch2_median_bNumber
Ch2 SignalNoiseRatioch2_signalnoiseratioch2_signalnoiseratioNumber
Ch2 % > B + 1 SDch2_b_1_sdch2_b_1_sdNumber
Ch2 % > B + 2 SDch2_b_2_sdch2_b_2_sdNumber

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