Abstract
Metazoan embryogenesis is controlled by a limited number of signaling modules that are used repetitively at successive developmental stages. The development of social amoebas shows similar reiterated use of cAMP-mediated signaling. In the model Dictyostelium discoideum, secreted cAMP acting on 4 cAMP receptors (cARs1-4) coordinates cell movement during aggregation and fruiting body formation, and induces the expression of aggregation and sporulation genes at consecutive developmental stages. To identify hierarchy in the multiple roles of cAMP, we investigated cAR heterogeneity and function across the social amoeba phylogeny. The gene duplications that yielded cARs 2-4 occurred late in evolution. Many species have only a cAR1 ortholog that duplicated independently in the Polysphondylids and Acytostelids. Disruption of both cAR genes of Polysphondylium pallidum (Ppal) did not affect aggregation, but caused complete collapse of fruiting body morphogenesis. The stunted structures contained disorganized stalk cells, which supported a mass of cysts instead of spores; cAMP triggered spore gene expression in Ppal, but not in the cAR null mutant, explaining its sporulation defect. Encystation is the survival strategy of solitary amoebas, and lower taxa, like Ppal, can still encyst as single cells. Recent findings showed that intracellular cAMP accumulation suffices to trigger encystation, whereas it is a complementary requirement for sporulation. Combined, the data suggest that cAMP signaling in social amoebas evolved from cAMP-mediated encystation in solitary amoebas; cAMP secretion in aggregates prompted the starving cells to form spores and not cysts, and additionally organized fruiting body morphogenesis. cAMP-mediated aggregation was the most recent innovation.
| Original language | English |
|---|---|
| Pages (from-to) | 7089-7094 |
| Number of pages | 6 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Volume | 106 |
| Issue number | 17 |
| DOIs | |
| Publication status | Published - 28 Apr 2009 |
Keywords
- Developmental signaling
- Evolution of multicellularity
- Dictyostelia
- Amoebozoa
- Adenylyl cyclase G
- Dictyostelium discoideum (Dd)
- Polysphondylium pallidum
- Signal transduction
- Social amebas
- Prespore differentiation
- Normal morphogenesis
- Cyclic AMP
- Gene
- Protein
Cite this
}
Activated cAMP receptors switch encystation into sporulation. / Kawabe, Yoshinori; Morio, Takahiro; James, John L.; Prescott, Alan R.; Tanaka, Yoshimasa; Schaap, Pauline (Lead / Corresponding author).
In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 106, No. 17, 28.04.2009, p. 7089-7094.Research output: Contribution to journal › Article
TY - JOUR
T1 - Activated cAMP receptors switch encystation into sporulation
AU - Kawabe, Yoshinori
AU - Morio, Takahiro
AU - James, John L.
AU - Prescott, Alan R.
AU - Tanaka, Yoshimasa
AU - Schaap, Pauline
PY - 2009/4/28
Y1 - 2009/4/28
N2 - Metazoan embryogenesis is controlled by a limited number of signaling modules that are used repetitively at successive developmental stages. The development of social amoebas shows similar reiterated use of cAMP-mediated signaling. In the model Dictyostelium discoideum, secreted cAMP acting on 4 cAMP receptors (cARs1-4) coordinates cell movement during aggregation and fruiting body formation, and induces the expression of aggregation and sporulation genes at consecutive developmental stages. To identify hierarchy in the multiple roles of cAMP, we investigated cAR heterogeneity and function across the social amoeba phylogeny. The gene duplications that yielded cARs 2-4 occurred late in evolution. Many species have only a cAR1 ortholog that duplicated independently in the Polysphondylids and Acytostelids. Disruption of both cAR genes of Polysphondylium pallidum (Ppal) did not affect aggregation, but caused complete collapse of fruiting body morphogenesis. The stunted structures contained disorganized stalk cells, which supported a mass of cysts instead of spores; cAMP triggered spore gene expression in Ppal, but not in the cAR null mutant, explaining its sporulation defect. Encystation is the survival strategy of solitary amoebas, and lower taxa, like Ppal, can still encyst as single cells. Recent findings showed that intracellular cAMP accumulation suffices to trigger encystation, whereas it is a complementary requirement for sporulation. Combined, the data suggest that cAMP signaling in social amoebas evolved from cAMP-mediated encystation in solitary amoebas; cAMP secretion in aggregates prompted the starving cells to form spores and not cysts, and additionally organized fruiting body morphogenesis. cAMP-mediated aggregation was the most recent innovation.
AB - Metazoan embryogenesis is controlled by a limited number of signaling modules that are used repetitively at successive developmental stages. The development of social amoebas shows similar reiterated use of cAMP-mediated signaling. In the model Dictyostelium discoideum, secreted cAMP acting on 4 cAMP receptors (cARs1-4) coordinates cell movement during aggregation and fruiting body formation, and induces the expression of aggregation and sporulation genes at consecutive developmental stages. To identify hierarchy in the multiple roles of cAMP, we investigated cAR heterogeneity and function across the social amoeba phylogeny. The gene duplications that yielded cARs 2-4 occurred late in evolution. Many species have only a cAR1 ortholog that duplicated independently in the Polysphondylids and Acytostelids. Disruption of both cAR genes of Polysphondylium pallidum (Ppal) did not affect aggregation, but caused complete collapse of fruiting body morphogenesis. The stunted structures contained disorganized stalk cells, which supported a mass of cysts instead of spores; cAMP triggered spore gene expression in Ppal, but not in the cAR null mutant, explaining its sporulation defect. Encystation is the survival strategy of solitary amoebas, and lower taxa, like Ppal, can still encyst as single cells. Recent findings showed that intracellular cAMP accumulation suffices to trigger encystation, whereas it is a complementary requirement for sporulation. Combined, the data suggest that cAMP signaling in social amoebas evolved from cAMP-mediated encystation in solitary amoebas; cAMP secretion in aggregates prompted the starving cells to form spores and not cysts, and additionally organized fruiting body morphogenesis. cAMP-mediated aggregation was the most recent innovation.
KW - Developmental signaling
KW - Evolution of multicellularity
KW - Dictyostelia
KW - Amoebozoa
KW - Adenylyl cyclase G
KW - Dictyostelium discoideum (Dd)
KW - Polysphondylium pallidum
KW - Signal transduction
KW - Social amebas
KW - Prespore differentiation
KW - Normal morphogenesis
KW - Cyclic AMP
KW - Gene
KW - Protein
UR - http://www.scopus.com/inward/record.url?scp=66349087653&partnerID=8YFLogxK
U2 - 10.1073/pnas.0901617106
DO - 10.1073/pnas.0901617106
M3 - Article
C2 - 19369200
VL - 106
SP - 7089
EP - 7094
JO - Proceedings of the National Academy of Sciences
JF - Proceedings of the National Academy of Sciences
SN - 0027-8424
IS - 17
ER -