High-throughput analysis of spatio-temporal dynamics in Dictyostelium

Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
Genome biology (Impact Factor: 10.81). 02/2007; 8(7):R144. DOI: 10.1186/gb-2007-8-7-r144
Source: PubMed


We demonstrate a time-lapse video approach that allows rapid examination of the spatio-temporal dynamics of Dictyostelium cell populations. Quantitative information was gathered by sampling life histories of more than 2,000 mutant clones from a large mutagenesis collection. Approximately 4% of the clonal lines showed a mutant phenotype at one stage. Many of these could be ordered by clustering into functional groups. The dataset allows one to search and retrieve movies on a gene-by-gene and phenotype-by-phenotype basis.

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    • "The majority of microbial genotype-to-phenotype studies focus on a single characteristic, growth rate (Liu et al., 2010; North et al., 2012), but a few have attempted to characterize more complex multicellular traits. In Pseudomonas aeruginosa, confocal microscopy was used to study biofilm density patterns in mutant strains using a high-throughput assay (Pommerenke et al., 2010), and in Dictyostelium discoideum, time lapse images of ~2000 mutant strains were used to identify and characterize changes in the formation of fruiting bodies (Sawai et al., 2007). In both of these studies, despite the acquisition of detailed image data, the percentage of strains displaying discernably mutant traits remained below 10%. "
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    • "Roco7 and Roco9 are expressed mostly during aggregation, similar to GbpC. Although roco5-null cells were previously identified in a large screen for mutants with defects in the developmental cycle (Sawai et al., 2007), they did not show any recognizable developmental phenotype. In the contrary roco11- null cells show mild developmental defects: these cells develop significantly larger fruiting bodies; in particular, the multicellular structures have longer stalks compared to wild-type cells, re-expression of Roco11 in roco11-null cells rescues this defect. "

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    • "In addition, no caspases or metacaspases are encoded by the D. discoideum genome (Eichinger et al., 2005). On the other hand, the MAPK proteins ErkA and ErkB have been implicated in various growth, developmental, and defense functions in the D. discoideum life-cycle (Sawai et al., 2007; Segall et al., 1995). Interestingly, recent evidence indicates that the D. discoideum MAPK response is also involved in host responses to the pathogen L. pneumophila (Li et al., 2009). "
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