Project description:Micractinium conductrix SAG 241.80 secretes sugars (especially maltose) at pH 5.7 while very little sugar is found at pH 7.6. Another algae, Chlorella sorokiniana does not secrete sugars at either pH. We evaluated the transcriptional profiles of both species of algae at pH 5.7 and 7.6 to make comparisons in the regulation of potential genes involved in these pathways. Overall design: Micractinium conductrix was grown in modified freshwater SAG medium and Chlorella sorokiniana was grown in a modified freshwater medium and both were grown at both pH 5.7 and pH 7.6. All samples were harvested at similar times and total RNA was extracted. Libraries were constructed and sequenced using HiSeq 2500 Illumina sequencing technique.
Project description:Green hydra (Hydra viridissima) harbors endosymbiotic Chlorella and have established a mutual relation. To identify the host hydra genes involved in the specific symbiotic relationship, transcriptomes of intact H. viridissima colonized with symbiotic Chlorella strain A99, aposymbiotic H.viridissima and H. viridissima artificially infected with other symbiotic Chlorella were compared by microarray analysis. The results indicated that genes involved in nutrition supply to Chlorella were upregulated in the symbiotic hydra. In addition, it was induced by supply of photosynthates from the symbiont to the host, suggesting cooperative metabolic interaction between the host and the symbiotic algae. Overall design: For the microarray analysis, we used intact H.viridissima A99 in asexual phase, that in sexual phase, aposymbiotic H.viridissima A99 which removed symbiotic algae, and H.viridissima A99 which removed the symbiotic algae and artificially infected Chlorella variabilis NC64A known as the symbiotic Chlorella of paramecium. The experiments using three biological replicates for each sample were performed using the total RNA from whole polyps after light exposure for six hour.
Project description:Chlorella has been reported to have various physiological activities, including antiarteriosclerotic, cholesterol-lowering, anti-inflammatory, and immunoregulatory effects. However, there has been no report on the long-term effects of chlorella ingestion on immunity. In the present study, 4- to 10-week-old (young) and 4- to 50-week-old (old) female BALB/c mice were sensitized or not with ovalbumin (OVA), and given basic diet containing chlorella powder at 2% or basic diet alone. The effects of chlorella ingestion on immunity were investigated by measurement of splenic cytokines and immunoglobulin (Ig), analysis of T- and B-cells in the spleen and small intestine by flow cytometry, and analysis of the liver by DNA microarray. Results were compared between the young and old, OVA-sensitized and -nonsensitized, and chlorella and non-chlorella ingestion groups. Production of interferon-γ (IFN-γ) was maintained in the nonsensitized old groups, and ratios of T-helper type 1 (Th1) to T-helper type 2 (Th2) cells were similar in the young and old groups. In addition, overproduction of OVA-specific Igs due to OVA sensitization was strongly suppressed, and significant immunotolerance was exhibited irrespective of age. In addition, suppression of T-cell decreases in the spleen due to aging and suppression of changes in T- and B-cells due to OVA sensitization in the small intestinal lymph were demonstrated on flow cytometric analyses. On DNA microarray analysis, immune-related terms including IL11 and major histocompatibility complex (MHC) class 1 were detected, and expression of genes was shown, which were related to IL1-linked genes and complex involving macrophages from the pathways of cytokines and inflammatory response. In addition, suppressions of declined lipid metabolism and energy production were also suggested. Although how the ingredients in chlorella were involved in these changes is unclear, our findings suggest that prevention of decrease in acquired immunity by aging and induction of strong immunotolerance occurred following chlorella ingestion. The Young Control group and Old Control group were fed normal food, and the Old Chlorella intake group was fed food including 2.0% Chlorella powder. The total RNA was isolated from liver and samples was pooled for each group (n = 6 for each group). A table of normalized log2 ratios (where numerator is sample expression data, and denominator is all sample median data) is linked below as a supplementary file.