10 research outputs found
MOESM2 of Artificial miRNA inhibition of phosphoenolpyruvate carboxylase increases fatty acid production in a green microalga Chlamydomonas reinhardtii
Additional file 2: Figure S2. The growth curve of transgenic C. reinhardtii. aRP1.1, aRP1.2 were derived from individual amicroRNA- PEPC1 transformants, and aRP2.1, aRP2.2, aRP2.3 were from amicroRNA- PEPC2 transformants. C. reinhardtii CC-849 is the wild type. Introduction of amicroRNA- PEPC1 and amicroRNA- PEPC2 has no effect on the growth of transgenic algae
Hg<sup>2+</sup> removal and Hg<sup>2+</sup> biouptake from 10 mg /L Hg<sup>2+</sup> solution by unmodified R1 cells (control) and R1 chemically modified to block carboxyl, amino and hydroxyl, and phosphate groups, respectively.
<p>After chemical modification, the cells were washed twice with ddH<sub>2</sub>O, harvested by centrifugation and resuspended in10 mg/L Hg<sup>2+</sup> solution for 2 h biouptake.</p
Simultaneous process of cell propagation and Hg<sup>2+</sup> removal by actively growing R1 from 0.1YPD media.
<p>a: Time course of the simultaneous process of cell propagation and Hg<sup>2+</sup> removal. 0.1YPD medium was complemented with 10 mg/L Hg<sup>2+</sup>. b: Comparison of Hg<sup>2+</sup> removal and cell growth by actively growing R1 under different concentrations of Hg<sup>2+</sup> after 30 h cultivation.</p
Comparison of Hg<sup>2+</sup> removal ratio and Hg<sup>2+</sup> biouptake by R1 from aqueous solutions containing different concentrations of organic substances.
<p>The control was made of ddH<sub>2</sub>O and contained no organic substance. 0.1YPD and 0.01YPD represented diluted (1:10 and 1:100) YPD media. All solutions were complemented with 10 mg/L Hg<sup>2+</sup>.</p
Equilibrium biouptake of Hg<sup>2+</sup>.
<p>Equilibrium biouptake of Hg<sup>2+</sup>.</p
Growth of R1 in 0.1 YPD medium complemented with different concentration of Hg<sup>2+</sup>.
<p>Growth of R1 in 0.1 YPD medium complemented with different concentration of Hg<sup>2+</sup>.</p
Table_1_Flagella-Associated WDR-Containing Protein CrFAP89 Regulates Growth and Lipid Accumulation in Chlamydomonas reinhardtii.docx
<p>WD40-repeat (WDR) domain-containing proteins are subunits of multi-protein E3 ligase complexes regulating various cellular and developmental activities in eukaryotes. Chlamydomonas reinhardtii serves as a model organism to study lipid metabolism in microalgae. Under nutrition deficient conditions, C. reinhardtii accumulates lipids for survival. The proteins in C. reinhardtii flagella have diverse functions, such as controlling the motility and cell cycle, and environment sensing. Here, we characterized the function of CrFAP89, a flagella-associated WDR-containing protein, which was identified from C. reinhardtii nitrogen deficiency transcriptome analysis. Quantitative real time-PCR showed that the transcription levels of CrFAP89 were significantly enhanced upon nutrient deprivation, including nitrogen, sulfur, or iron starvation, which is considered an effective condition to promote triacylglycerol (TAG) accumulation in microalgae. Under sulfur starvation, the expression of CrFAP89 was 32.2-fold higher than the control. Furthermore, two lines of RNAi mutants of CrFAP89 were generated by transformation, with gene silencing of 24.9 and 16.4%, respectively. Inhibiting the expression of the CrFAP89 gene drastically increased cell density by 112–125% and resulted in larger cells, that more tolerant to nutrition starvation. However, the content of neutral lipids declined by 12.8–19.6%. The fatty acid content in the transgenic algae decreased by 12.4 and 13.3%, mostly decreasing the content of C16:0, C16:4, C18, and C20:1 fatty acids, while the C16:1 fatty acid in the CrFAP89 RNAi lines increased by 238.5 to 318.5%. Suppressed expression of TAG biosynthesis-related genes, such as CrDGAT1 and CrDGTTs, were detected in CrFAP89 gene silencing cells, with a reduction of 16–78%. Overall our results suggest that down-regulating of the expression of CrFAP89 in C. reinhardtii, resulting in an increase of cell growth and a decrease of fatty acid synthesis with the most significant decrease occurring in C16:0, C16:4, C18, and C20:1 fatty acid. CrFAP89 might be a regulator for lipid accumulation in C. reinhardtii.</p
Phylogenetic tree.
<p>Bootstrap values (expressed as percentages of 1000 replications) are shown at the branch points. Bar, 0.01 nucleotide substitution rate (Knuc) units.</p
XPS analysis of R1 before/after Hg<sup>2+</sup> uptake.
<p>a: XPS spectra of R1 and Hg-laden R1. b: Calculation of peak area based on origin fitting.</p
MOESM1 of Improved photobio-H2 production regulated by artificial miRNA targeting psbA in green microalga Chlamydomonas reinhardtii
Additional file 1: Figure S1. Full-length gels of Fig. 3