Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.1 (sulfatase)
 3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Forward genetics was used to isolate Chlamydomonas reinhardtii mutants with altered abilities to acclimate to sulfur (S) deficiency. The ars76 mutant has a deletion that eliminates several genes, including VACUOLAR TRANSPORTER CHAPERONE1 (VTC1), which encodes a component of a polyphosphate polymerase complex. The ars76 mutant cannot accumulate arylsulfatase protein or mRNA and shows marked alterations in levels of many transcripts encoded by genes induced during S deprivation. The mutant also shows little acidocalcisome formation compared with wild-type, S-deprived cells and dies more rapidly than wild-type cells following exposure to S-, phosphorus-, or nitrogen (N)-deficient conditions. Furthermore, the mutant does not accumulate periplasmic L-amino acid oxidase during N deprivation. Introduction of the VTC1 gene specifically complements the ars76 phenotypes, suggesting that normal acidocalcisome formation in cells deprived of S requires VTC1. Our data also indicate that a deficiency in acidocalcisome function impacts trafficking of periplasmic proteins, which can then feed back on the transcription of the genes encoding these proteins. These results and the reported function of vacuoles in degradation processes suggest a major role of the acidocalcisome in reshaping the cell during acclimation to changing environmental conditions.
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PMID:Critical function of a Chlamydomonas reinhardtii putative polyphosphate polymerase subunit during nutrient deprivation. 2528 87

Chlamydomonas reinhardtii fox1 gene encodes a ferroxidase that is involved in cellular Fe uptake and highly induced during Fe deficient conditions. In an effort to identify fox1 promoter regulatory elements, an insertional library was generated in a transgenic Chlamydomonas strain (2A38) harboring an arylsulfatase (ARS) reporter gene driven by the fox1 promoter. Mutants with a defective response to low iron conditions were selected for further study. Among these, a strain containing a disrupted femu2 gene was identified. Activation of the fox1 promoter by the femu2 gene product was confirmed by silencing the femu2 gene using RNA interference. In three femu2 RNAi transgenic lines (IR3, IR6, and IR7), ARS reporter gene activities declined by 84.3%, 86.4%, and 88.8%, respectively under Fe deficient conditions. Furthermore, RT-PCR analysis of both the femu2 mutant and the RNAi transgenic lines showed significantly decreased transcript abundance of the endogenous fox1 gene under Fe deficient conditions. Amino acid sequence analysis of the femu2 gene product identified three potential C2H2 zinc finger (ZF) motifs and a nuclear localization study suggests that FEMU2 is localized to the nucleus. In addition, a potential FEMU2 binding site ((G/T)TTGG(G/T)(G/T)T) was identified using PCR-mediated random binding site selection. Taken together, this evidence suggests that FEMU2 is involved in up-regulation of the fox1 gene in Fe deficient cells.
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PMID:A C2H2 zinc finger protein FEMU2 is required for fox1 expression in Chlamydomonas reinhardtii. 2548 40

Efficient protein secretion is a desirable trait for any recombinant protein expression system, together with simple, low-cost, and defined media, such as the typical media used for photosynthetic cultures of microalgae. However, low titers of secreted heterologous proteins are usually obtained, even with the most extensively studied microalga Chlamydomonas reinhardtii, preventing their industrial application. In this study, we aimed to expand and evaluate secretory signal peptides (SP) for heterologous protein secretion in C. reinhardtii by comparing previously described SP with untested sequences. We compared the SPs from arylsulfatase 1 and carbonic anhydrase 1, with those of untried SPs from binding protein 1, an ice-binding protein, and six sequences identified in silico. We identified over 2000 unique SPs using the SignalP 4.0 software. mCherry fluorescence was used to compare the protein secretion of up to 96 colonies for each construct, non-secretion construct, and parental wild-type cc1690 cells. Supernatant fluorescence varied according to the SP used, with a 10-fold difference observed between the highest and lowest secretors. Moreover, two SPs identified in silico secreted the highest amount of mCherry. Our results demonstrate that the SP should be carefully selected and that efficient sequences can be coded in the C. reinhardtii genome. The SPs described here expand the portfolio available for research on heterologous protein secretion and for biomanufacturing applications.
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PMID:Comparison of secretory signal peptides for heterologous protein expression in microalgae: Expanding the secretion portfolio for Chlamydomonas reinhardtii. 2940 37

Chlamydomonas reinhardtii, a single-celled green alga, is a powerful microbial experimental system for understanding gene function. As a consequence of a high-quality genome sequence, community-wide efforts for gene model refinement and annotation, resources for strain collections and robust molecular techniques, research with this organism has significantly expanded in the past few decades. In two companion chapters, we outline colorimetric and fluorescence-based methodologies for genetic reporter systems in Chlamydomonas, which can be used to investigate and delineate gene expression and regulatory mechanisms. Here, we describe protocols for arylsulfatase activity assays using ARS2, activity of which can be measured either quantitatively or qualitatively, and in low (individual sample) or high (96-well format) throughput.
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PMID:Gene Expression Analysis by Arylsulfatase Assays in the Green Alga Chlamydomonas reinhardtii. 2967 Dec 69


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