Aggregation and Differentiation in the Cellular Slime Molds

Bonner, John Tyler

doi:10.1146/annurev.mi.25.100171.000451

Cited by 110 publications

(32 citation statements)

References 31 publications

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“…Vegetative cells feed on bacteria and other microbes and scavenge for food by sensing and migrating toward FA and other potential chemical signals (Maeda et al, 2009;Pan et al, 1972). When nutrients are limiting, cells enter a cAMPdependent developmental cycle that culminates in the formation of multicellular fruiting bodies (Bonner, 1971;Bonner, 1978;Katoh et al, 2007;Loomis, 1979). D. discoideum cells are highly chemotactic during these early stages of development and are very polarized, forming a defined front and rear.…”

Section: Introductionmentioning

confidence: 99%

Delineating the core regulatory elements crucial for directed cell migration by examining folic-acid-mediated responses

Srinivasan

Wright

Hames

et al. 2013

Journal of Cell Science

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SummaryDictyostelium discoideum shows chemotaxis towards folic acid (FA) throughout vegetative growth, and towards cAMP during development. We determined the spatiotemporal localization of cytoskeletal and signaling molecules and investigated the FA-mediated responses in a number of signaling mutants to further our understanding of the core regulatory elements that are crucial for cell migration. Proteins enriched in the pseudopods during chemotaxis also relocalize transiently to the plasma membrane during uniform FA stimulation. In contrast, proteins that are absent from the pseudopods during migration redistribute transiently from the PM to the cytosol when cells are globally stimulated with FA. These chemotactic responses to FA were also examined in cells lacking the GTPases Ras C and G. Although Ras and phosphoinositide 3-kinase activity were significantly decreased in Ras G and Ras C/G nulls, these mutants still migrated towards FA, indicating that other pathways must support FA-mediated chemotaxis. We also examined the spatial movements of PTEN in response to uniform FA and cAMP stimulation in phospholipase C (PLC) null cells. The lack of PLC strongly influences the localization of PTEN in response to FA, but not cAMP. In addition, we compared the gradient-sensing behavior of polarized cells migrating towards cAMP to that of unpolarized cells migrating towards FA. The majority of polarized cells make U-turns when the cAMP gradient is switched from the front of the cell to the rear. Conversely, unpolarized cells immediately extend pseudopods towards the new FA source. We also observed that plasma membrane phosphatidylinositol 3,4,5-trisphosphate [PtdIns(3,4,5)P 3 ] levels oscillate in unpolarized cells treated with Latrunculin-A, whereas polarized cells had stable plasma membrane PtdIns(3,4,5)P 3 responses toward the chemoattractant gradient source. Results were similar for cells that were starved for 4 hours, with a mixture of polarized and unpolarized cells responding to cAMP. Taken together, these findings suggest that similar components control gradient sensing during FA-and cAMP-mediated motility, but the response of polarized cells is more stable, which ultimately helps maintain their directionality.

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Section: Introductionmentioning

confidence: 99%

Delineating the core regulatory elements crucial for directed cell migration by examining folic-acid-mediated responses

Srinivasan

Wright

Hames

et al. 2013

Journal of Cell Science

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“…Although the influence of low M r factors on l~'ctyostelium development has been acknowledged since the mysterious 'acrasine' turned out to be cAMP [3 ], experimental evidence suggests that the popularity of cAMP may have eclipsed the influence of other low M r factors, whose diffusibility is also in favour of their acting as intercellular 'communication' molecules.…”

Section: Discussionmentioning

confidence: 99%

Fluorescent products secreted by Dictyostelium discoïdeum cells which are able to aggregate

Tatischeff¹,

Klein²

1982

FEBS Letters

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Section: Introductionmentioning

confidence: 90%

“…Sussman and his co-workers (for a review, see Sussman & Sussman, 1969) have focused their attention on the role of transcription and translation of enzymes while Wright (1966, 1972) and her associates look to the role of enzyme substrates and products in the chemical control of development. As has been pointed out (Francis, 1969;Bonner, 1971; Newell, 197r), there is no conflict between these two proposed mechanisms and it is reasonable to assume that both play a role in development.Development leads to the production of both stalk cells and spores and these exhibit different metabolic activities during development. By dissection of individual slugs, Newell, Ellingson & Sussman (I 969) demonstrated that different programmes of enzyme synthesis occurred during the development of stalk cells and spores.…”

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confidence: 90%

Enzyme Activity Changes during Cyclic AMP-induced Stalk Cell Differentiation in p4, a Variant of Dictyostelium discoideum

Hamilton

Chia

1975

Journal of General Microbiology

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S U M M A R YThe ~4 variant of Dictyostelium discoideum is characterized by the production of fruiting structures in which the overall proportion of stalk to spore material is increased, relative to the wild type. The altered morphology of the mutant is due to increased sensitivity to cyclic AMP which promotes stalk cell differentiation. In the presence of I O -~ M-cyclic AMP the entire population of ~4 amoebae forms clumps of stalk cells on the surface of the dialysis membrane support.Measurement of changes in activity of a range of developmentally-regulated enzymes during the development of ~4 in the presence and absence of cyclic AMP has allowed us to identify three classes of enzyme : (i) Those, such as /3-glucosidase 11, trehalose-6-phosphate synthetase and uridine diphosphogalactose-4-epimerase, which are required for the production of spores. (ii) Enzymes, primarily but perhaps not exclusively, required during stalk cell formation, Typical of these are N-acetylglucosaminidase and alkaline phosphatase. (iii) General enzymes, such as threonine dehydrase, a-mannosidase and uridine diphosphoglucose pyrophosphorylase, which are present in both pre-stalk and pre-spore cells and appear to be necessary for the development of both cell types. I N T R O D U C T I O NChanges in enzyme specific activities during the development of the cellular slime moulds have been studied to understand the biochemical mechanisms underlying development. Sussman and his co-workers (for a review, see Sussman & Sussman, 1969) have focused their attention on the role of transcription and translation of enzymes while Wright (1966, 1972) and her associates look to the role of enzyme substrates and products in the chemical control of development. As has been pointed out (Francis, 1969;Bonner, 1971; Newell, 197r), there is no conflict between these two proposed mechanisms and it is reasonable to assume that both play a role in development.Development leads to the production of both stalk cells and spores and these exhibit different metabolic activities during development. By dissection of individual slugs, Newell, Ellingson & Sussman (I 969) demonstrated that different programmes of enzyme synthesis occurred during the development of stalk cells and spores. This approach is however limited to that period in development when pre-stalk and pre-spore cells are separable in the aggregate, and does not allow either to be examined throughout development. Since a separation of spore cell development from stalk cell development is possible in the variant ~4 , we have used it in our studies. In the development of ~4 there is both stalk cell and spore differentiation, .but in the development of ~4 amoebae with 1 0 -4 M-

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Aggregation and Differentiation in the Cellular Slime Molds

Cited by 110 publications

References 31 publications

Delineating the core regulatory elements crucial for directed cell migration by examining folic-acid-mediated responses

Delineating the core regulatory elements crucial for directed cell migration by examining folic-acid-mediated responses

Fluorescent products secreted by Dictyostelium discoïdeum cells which are able to aggregate

Enzyme Activity Changes during Cyclic AMP-induced Stalk Cell Differentiation in p4, a Variant of Dictyostelium discoideum

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