Ectopic expression of constitutively activated Ral GTPase inhibits cell shape changes during Drosophila eye development

Kazunobu Sawamoto, Chiharu Yamada, Shosei Kishida, Yuki Hirota, Akiko Taguchi, Akira Kikuchi, Hideyuki Okano

Research output: Contribution to journalArticle

18 Citations (Scopus)


The small GTP-binding protein Ral is activated by RalGDS, one of the effector molecules for Ras. Active Ral binds to a GTPase activating protein for CDC42 and Rac. Although previous studies suggest a role for Ral in the regulation of CDC42 and Rac, which are involved in arranging the cytoskeleton, its in in vivo function is largely unknown. To examine the effect of overexpressing Ral on development, transgenic Drosophila were generated that overexpress wild-type or mutated Ral during eye development. While wild-type Ral caused no developmental defects, expression of a constitutively activated protein resulted in a rough eye phenotype. Activated Rat did not affect cell fate determination in the larval eye discs but caused severe disruption of the ommatidial organization later in pupal development. Phalloidin staining showed that activated Ral perturbed the cytoskeletal structure and cell shape changes during pupal development. This phenotype is similar to that caused by RhoA overexpression. In addition, the phenotype was synergistically enhanced by the coexpression of RhoA. These results suggest that Ral functions to control the cytoskeletal structure required for cell shape changes during Drosophila development.

Original languageEnglish
Pages (from-to)1967-1974
Number of pages8
Issue number11
Publication statusPublished - 1999 Mar 18



  • Actin
  • Cell shape
  • Drosophila
  • Ral

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Cancer Research

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