FUNCTIONAL MAPPING OF THE BRANCHED SIGNAL TRANSDUCTION PATHWAY THAT CONTROLS SPORULATION IN Physarum polycephalum

Starostzik, Christine; Marwan, Wolfgang

doi:10.1111/j.1751-1097.1995.tb09158.x

Cited by 33 publications

(27 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Even at saturating photon exposure, certain plasmodia may fail to sporulate. The dose–response curve typically saturates at values between 80–100% of sporulating plasmodia when grown and maintained under our experimental conditions (Starostzik & Marwan, 1995a, b; Marwan & Starostzik, ).…”

Section: Resultsmentioning

confidence: 92%

“…While the 454‐sequencing experiments were performed with pooled RNA samples isolated from several individual plasmodia in order to obtain a statistically representative result, we now analysed RNA samples of individual plasmodial cells to detect possible cell‐to‐cell variations in the gene expression patterns within an apparently homogeneous cell population (see Materials and methods). In general, the probability that an individual plasmodium will sporulate in response to a light pulse depends on the photon exposure (the number of photons applied) and varies in a dosage‐dependent manner from 0% to almost 100% (Starostzik & Marwan, 1995a, b). The developmental decision of an individual plasmodium is always all or none in terms of sporulation, suggesting stochasticity in the developmental decision which, when made, evenly encompasses the entire multinucleate cell mass.…”

Section: Resultsmentioning

confidence: 99%

“…Sporulation of a far‐red stimulated plasmodium can be prevented by a subsequent red light pulse given not later than 2 h after the far‐red pulse or by glucose fed not later than 5–6 h after far‐red, suggesting the occurrence of two irreversible steps that are presumably mediated by two subsequent switch‐like events (Starostzik & Marwan, 1995a, b). The data of Fig.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Futile attempts to differentiate provide molecular evidence for individual differences within a population of cells during cellular reprogramming

Hoffmann

Tesmer

Souquet³

et al. 2012

FEMS Microbiol Lett

Self Cite

View full text Add to dashboard Cite

The heterogeneity of cell populations and the influence of stochastic noise might be important issues for the molecular analysis of cellular reprogramming at the system level. Here, we show that in Physarum polycephalum, the expression patterns of marker genes correlate with the fate decision of individual multinucleate plasmodial cells that had been exposed to a differentiation-inducing photostimulus. For several hours after stimulation, the expression kinetics of PI-3-kinase, piwi, and pumilio orthologs and other marker genes were qualitatively similar in all stimulated cells but quantitatively different in those cells that subsequently maintained their proliferative potential and failed to differentiate accordingly. The results suggest that the population of nuclei in an individual plasmodium behaves synchronously in terms of gene regulation to an extent that the plasmodium provides a source for macroscopic amounts of homogeneous single-cell material for analysing the dynamic processes of cellular reprogramming. Based on the experimental findings, we predict that circuits with switch-like behaviour that control the cell fate decision of a multinucleate plasmodium operate through continuous changes in the concentration of cellular regulators because the nuclear population suspended in a large cytoplasmic volume damps stochastic noise.

show abstract

Section: Resultsmentioning

confidence: 92%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Futile attempts to differentiate provide molecular evidence for individual differences within a population of cells during cellular reprogramming

Hoffmann

Tesmer

Souquet³

et al. 2012

FEMS Microbiol Lett

Self Cite

View full text Add to dashboard Cite

show abstract

“…Some genes are differentially regulated even at 2 h (Hoffmann et al . ) which is far upstream the point of no return where sporulation of the induced plasmodium can still be prevented by feeding glucose (Starostzik & Marwan , ). This suggests that sensory signal transduction, signal processing at the protein level, and gene regulation at least to some extent are chronologically interwoven.…”

Section: Resultsmentioning

confidence: 99%

Physarum polycephalum mutants in the photocontrol of sporulation display altered patterns in the correlated expression of developmentally regulated genes

et al. 2013

Self Cite

View full text Add to dashboard Cite

Physarum polycephalum is a lower eukaryote belonging to the amoebozoa group of organisms that forms macroscopic, multinucleate plasmodial cells during its developmental cycle. Plasmodia can exit proliferative growth and differentiate by forming fruiting bodies containing mononucleate, haploid spores. This process, called sporulation, is controlled by starvation and visible light. To genetically dissect the regulatory control of the commitment to sporulation, we have isolated plasmodial mutants that are altered in the photocontrol of sporulation in a phenotypic screen of N-ethyl-N-nitrosourea (ENU) mutagenized cells. Several non-sporulating mutants were analyzed by measuring the light-induced change in the expression pattern of a set of 35 genes using GeXP multiplex reverse transcription-polymerase chain reaction with RNA isolated from individual plasmodial cells. Mutants showed altered patterns of differentially regulated genes in response to light stimulation. Some genes clearly displayed pairwise correlation in terms of their expression level as measured in individual plasmodial cells. The pattern of pairwise correlation differed in various mutants, suggesting that different upstream regulators were disabled in the different mutants. We propose that patterns of pairwise correlation in gene expression might be useful to infer the underlying gene regulatory network.

show abstract

“…Cells were grown and collected under two different conditions: (i) a plasmodium starved for 6 days (competent D1 and D2 individual cell samples); and (ii) a plasmodium starved for 6 days, exposed to far red light for 30 minutes, and returned to the dark for 6.5 hours (L1 and L2 photoinduced cells; Table 1). During this time period the cell becomes irreversibly committed to sporulation 21. Samples were frozen with liquid nitrogen and Poly(A)+ RNA was isolated from the total RNA samples (by two rounds of oligo(dT) affinity chromatography), and fragmented with ultra-sound (4 pulses of 30 sec at 4 °C).…”

Section: Methodsmentioning

confidence: 99%

A Next-Generation Sequencing Approach to Study the Transcriptomic Changes during the Differentiation of Physarum at the Single-Cell Level

Barrantes

Leipzig

Marwan

2012

Gene�Regul Syst Bio

Self Cite

View full text Add to dashboard Cite

Physarum polycephalum is a unicellular eukaryote belonging to the amoebozoa group of organisms. The complex life cycle involves various cell types that differ in morphology, function, and biochemical composition. Sporulation, one step in the life cycle, is a stimulus-controlled differentiation response of macroscopic plasmodial cells that develop into fruiting bodies. Well-established Mendelian genetics and the occurrence of macroscopic cells with a naturally synchronous population of nuclei as source of homogeneous cell material for biochemical analyses make Physarum an attractive model organism for studying the regulatory control of cell differentiation. Here, we develop an approach using RNA-sequencing (RNA-seq), without needing to rely on a genome sequence as a reference, for studying the transcriptomic changes during stimulus-triggered commitment to sporulation in individual plasmodial cells. The approach is validated through the obtained expression patterns and annotations, and particularly the results from up- and downregulated genes, which correlate well with previous studies.

show abstract

FUNCTIONAL MAPPING OF THE BRANCHED SIGNAL TRANSDUCTION PATHWAY THAT CONTROLS SPORULATION IN Physarum polycephalum

Cited by 33 publications

References 9 publications

Futile attempts to differentiate provide molecular evidence for individual differences within a population of cells during cellular reprogramming

Futile attempts to differentiate provide molecular evidence for individual differences within a population of cells during cellular reprogramming

Physarum polycephalum mutants in the photocontrol of sporulation display altered patterns in the correlated expression of developmentally regulated genes

A Next-Generation Sequencing Approach to Study the Transcriptomic Changes during the Differentiation of Physarum at the Single-Cell Level

Contact Info

Product

Resources

About