Your browser does not support JavaScript!

Proneural proteins Achaete and Scute associate with nuclear actin to promote formation of external sensory organs
Yun-Ling Hsiao1,2, Yu-Ju Chen1,2, Yi-Jie Chang1,2, Hsiao-Fong Yeh2, Yi-Chun Huang3 and Haiwei Pi1,2,*

Basic helix-loop-helix (bHLH) proneural proteins promote neurogenesis through transcriptional regulation. Although much is known about the tissue-specific regulation of proneural gene expression, how proneural proteins interact with transcriptional machinery to activate downstream target genes is less clear. Drosophila proneural proteins Achaete (Ac) and Scute (Sc) induce external sensory organ formation by activating neural precursor gene expression. Through co-immunoprecipitation and mass spectrometric analyses, we found that nuclear but not cytoplasmic actin associated with the Ac and Sc proteins in DrosophilaS2 cells. Daughterless (Da), the common heterodimeric partner of Drosophila bHLH proteins, was observed to associate with nuclear actin through proneural proteins. A yeast two-hybrid assay revealed that the binding specificity between actin and Ac or Sc was conserved in yeast nuclei without the presence of additional Drosophila factors. We further show that actin is required in external sensory organ formation. Reduction in actin gene activity impaired proneural-protein-dependent expression of the neural precursor genes, as well as formation of neural precursors. Furthermore, increased nuclear actin levels, obtained by expression of nucleus-localized actin, elevated Ac–Da-dependent gene transcription as well as Ac-mediated external sensory organ formation. Taken together, ourin vivoandin vitroobservations suggest a novel link for actin in proneural-protein-mediated transcriptional activation and neural precursor differentiation.

  • 友善列印
  • 新增到收藏夾
  • 分享
Voice Play