From drought sensing to developmental control: evolution of cyclic AMP signaling in social amoebas.
From drought sensing to developmental control: evolution of cyclic AMP signaling in social amoebas.
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DOI：
10.1093/molbev/msn156
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发表时间：
2008-10
影响因子：
10.7
通讯作者：
Schaap P
中科院分区：
文献类型：
--
作者：
Ritchie AV;van Es S;Fouquet C;Schaap P
变形虫和其他原生生物在面对环境压力时通常会包囊。尽管对介导包囊形成的信号传导途径知之甚少，但对网柱虫社会性变形虫孢子形成的类似过程有了更好的了解。在盘基网柄藻中，分泌的环腺苷酸（cAMP）介导饥饿阿米巴的聚集并诱导前孢子细胞的分化。细胞内cAMP作用于cAMP依赖性蛋白激酶（PKA）触发孢子的成熟，并在孢子头中的高渗透压的普遍条件下阻止它们的萌发。渗透调节剂激活的腺苷酸环化酶ACG产生cAMP用于前孢子分化和抑制孢子萌发。为了追溯ACG功能的起源，我们研究了ACG基因的保守性和功能的物种，跨越dictyostelid的进化。ACG基因，渗透激活的ACG活性，并在代表4个主要类群的网柱珊瑚属物种中检测到孢子萌发的调节。与衍生种D.盘状幼体中，许多基底网柱藻保留了来自孤立变形虫的包囊形成的祖先机制。在这些物种和孤立的阿米巴中，包囊形成是由饥饿或高渗透压独立触发的。渗压剂诱导的包囊形成伴随着cAMP的增加，并通过PKA的抑制来阻止，表明ACG和PKA活化介导了这种反应。我们建议，高渗透压信号干旱在土壤变形虫和发育cAMP信号在Dictyostelia已经从这种应激反应。
Amoebas and other protists commonly encyst when faced with environmental stress. Although little is known of the signaling pathways that mediate encystation, the analogous process of spore formation in dictyostelid social amoebas is better understood. In Dictyostelium discoideum, secreted cyclic AMP (cAMP) mediates the aggregation of starving amoebas and induces the differentiation of prespore cells. Intracellular cAMP acting on cAMP-dependent protein kinase (PKA) triggers the maturation of spores and prevents their germination under the prevalent conditions of high osmolality in the spore head. The osmolyte-activated adenylate cyclase, ACG, produces cAMP for prespore differentiation and inhibition of spore germination. To retrace the origin of ACG function, we investigated ACG gene conservation and function in species that span the dictyostelid phylogeny. ACG genes, osmolyte-activated ACG activity, and osmoregulation of spore germination were detected in species that represent the 4 major groups of Dictyostelia. Unlike the derived species D. discoideum, many basal Dictyostelia have retained the ancestral mechanism of encystation from solitary amoebas. In these species and in solitary amoebas, encystation is independently triggered by starvation or by high osmolality. Osmolyte-induced encystation was accompanied by an increase in cAMP and prevented by inhibition of PKA, indicating that ACG and PKA activation mediate this response. We propose that high osmolality signals drought in soil amoebas and that developmental cAMP signaling in the Dictyostelia has evolved from this stress response.
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DOI：
10.1126/science.1130670
发表时间：
2006-10-27
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Schaap P;Winckler T;Nelson M;Alvarez-Curto E;Elgie B;Hagiwara H;Cavender J;Milano-Curto A;Rozen DE;Dingermann T;Mutzel R;Baldauf SL
通讯作者：
Baldauf SL
影响因子：
2.7
作者：
SCHAAP, P;PINAS, JE;MEI, W
通讯作者：
MEI, W
DOI：
10.1073/pnas.0502238102
发表时间：
2005-05-03
影响因子：
11.1
作者：
Alvarez-Curto, E;Rozen, DE;Schaap, P
通讯作者：
Schaap, P
影响因子：
4.8
作者：
Coppi, A;Merali, S;Eichinger, D
通讯作者：
Eichinger, D
影响因子：
14.9
作者：
Finn RD;Mistry J;Tate J;Coggill P;Heger A;Pollington JE;Gavin OL;Gunasekaran P;Ceric G;Forslund K;Holm L;Sonnhammer EL;Eddy SR;Bateman A
通讯作者：
Bateman A