Faculty Opinions recommendation of Loss of Cln3 impacts protein secretion in the social amoeba Dictyostelium.

The social amoeba Dictyostelium discoideum is a versatile organism that is unusual in alternating between single-celled and multi-celled forms. It possesses highly-developed systems for cell motility and chemotaxis, phagocytosis, and developmental pattern formation. As a soil amoeba growing on microorganisms, it is exposed to many potential pathogens; it thus provides fruitful ways of investigating host-pathogen interactions and is emerging as an influential model for biomedical research.

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Role of epigenetics in unicellular to multicellular transition in Dictyostelium

Genome Biology ◽

10.1186/s13059-021-02360-9 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Simon Yuan Wang ◽

Elizabeth Ann Pollina ◽

I-Hao Wang ◽

Lindsay Kristina Pino ◽

Henry L. Bushnell ◽

...

Keyword(s):

Dictyostelium Discoideum ◽

Orthologous Gene ◽

Chromatin Accessibility ◽

Critical Event ◽

H3k4 Methylation ◽

Social Amoeba ◽

The Social ◽

Conserved Genes ◽

Multicellular Organisms

Abstract Background The evolution of multicellularity is a critical event that remains incompletely understood. We use the social amoeba, Dictyostelium discoideum, one of the rare organisms that readily transits back and forth between both unicellular and multicellular stages, to examine the role of epigenetics in regulating multicellularity. Results While transitioning to multicellular states, patterns of H3K4 methylation and H3K27 acetylation significantly change. By combining transcriptomics, epigenomics, chromatin accessibility, and orthologous gene analyses with other unicellular and multicellular organisms, we identify 52 conserved genes, which are specifically accessible and expressed during multicellular states. We validated that four of these genes, including the H3K27 deacetylase hdaD, are necessary and that an SMC-like gene, smcl1, is sufficient for multicellularity in Dictyostelium. Conclusions These results highlight the importance of epigenetics in reorganizing chromatin architecture to facilitate multicellularity in Dictyostelium discoideum and raise exciting possibilities about the role of epigenetics in the evolution of multicellularity more broadly.

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(Auto)Biographical reflections on the contributions of William F. Loomis (1940-2016) to Dictyostelium biology

The International Journal of Developmental Biology ◽

10.1387/ijdb.190224ak ◽

2019 ◽

Vol 63 (8-9-10) ◽

pp. 343-357

Author(s):

Adam Kuspa ◽

Gad Shaulsky

Keyword(s):

Cell Differentiation ◽

Molecular Biology ◽

Genetic Control ◽

Dictyostelium Discoideum ◽

University Of California ◽

High Dimensional ◽

Social Amoeba ◽

The Social ◽

The University ◽

High Dimensional Datasets

William Farnsworth Loomis studied the social amoeba Dictyostelium discoideum for more than fifty years as a professor of biology at the University of California, San Diego, USA. This biographical reflection describes Dr. Loomis’ major scientific contributions to the field within a career arc that spanned the early days of molecular biology up to the present day where the acquisition of high-dimensional datasets drive research. Dr. Loomis explored the genetic control of social amoeba development, delineated mechanisms of cell differentiation, and significantly advanced genetic and genomic technology for the field. The details of Dr. Loomis’ multifaceted career are drawn from his published work, from an autobiographical essay that he wrote near the end of his career and from extensive conversations between him and the two authors, many of which took place on the deck of his beachfront home in Del Mar, California.

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Reactive/Non-cooperative individuals advance Population's Synchronization: Modeling of Dictyostelium discoideum Concerted Signaling during Aggregation Phase

10.1101/2021.05.22.445258 ◽

2021 ◽

Author(s):

Zahra Eidi ◽

Najme Khorasani ◽

Mehdi Sadeghi

Keyword(s):

Life Form ◽

Single Cells ◽

Model Organism ◽

Spatiotemporal Patterns ◽

Chemical Signaling ◽

Relative Population ◽

Social Amoeba ◽

The Social ◽

Chemical Waves ◽

The Waves

Orchestrated chemical signaling of single cells sounds to be a linchpin of emerging organization and multicellular life form. The social amoeba Dictiostelium discoiudium is a well-studied model organism to explore overall pictures of grouped behavior in developmental biology. The chemical waves secreted by aggregating Dictiostelium is a superb example of pattern formation. The waves are either circular or spiral in shape, according to the incremental population density of a self-aggregating community of individuals. Here, we revisit the spatiotemporal patterns that appear in an excitable medium due to synchronization of randomly firing individuals, but with a more parsimonies attitude. According to our model, a fraction of these individuals is refusal to amplify external stimulants. Our simulations indicate that the cells enhance the system's asymmetry and as a result, nucleate early sustainable spiral territory zones, provided that their relative population does not exceed a tolerable threshold.

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