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Endogenous activation patterns of Cdc42 GTPase within Drosophila embryos.

ABSTRACT: Knowing when and where a given protein is activated within intact animals assists in elucidating its in vivo function. With the use of a genetically encoded A-probe (activation bioprobe), we revealed that Cdc42 guanosine triphosphatase (GTPase) remains inactive within Drosophila embryos during the first two-thirds of embryogenesis. Within the central nervous system where Cdc42 activity first becomes up-regulated, individual neurons display patterns restricted to specific subcellular compartments. At both organismal and cellular levels, Cdc42's endogenous activation patterns in the wild type allow predictions of where loss-of-function phenotypes will emerge in cdc42/cdc42 mutants. Genetic tests support the importance of suppressing endogenous Cdc42 activities until needed. Thus, bioprobe-assisted analysis uncovers how ubiquitously expressed signaling proteins control cellular events through continual regulation of their activities within animals.

SUBMITTER: Kamiyama D

PROVIDER: S-EPMC2729367 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Endogenous activation patterns of Cdc42 GTPase within Drosophila embryos.

Kamiyama Daichi D Chiba Akira A

Science (New York, N.Y.) 20090601 5932

Knowing when and where a given protein is activated within intact animals assists in elucidating its in vivo function. With the use of a genetically encoded A-probe (activation bioprobe), we revealed that Cdc42 guanosine triphosphatase (GTPase) remains inactive within Drosophila embryos during the first two-thirds of embryogenesis. Within the central nervous system where Cdc42 activity first becomes up-regulated, individual neurons display patterns restricted to specific subcellular compartments ...[more]

PMID: 19498173

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