Research article

The Drosophila STIM1 orthologue, dSTIM, has roles in cell fate specification and tissue patterning

Jean-Pierre Eid¹ , Alfonso Martinez Arias² , Hannah Robertson¹ , Gary R Hime^1,3 and Marie Dziadek⁴

¹  Department of Anatomy and Cell Biology, University of Melbourne, Victoria 3010, Australia

²  Department of Genetics, University of Cambridge, Cambridge, UK

³  Australian Research Council Centre of Excellence in Biotechnology and Development, University of Newcastle, Callaghan, NSW 2308, Australia

⁴  Cancer Research Program, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia

author email corresponding author email

BMC Developmental Biology 2008, 8:104doi:10.1186/1471-213X-8-104

Published:	24 October 2008

Abstract

Background

Mammalian STIM1 and STIM2 and the single Drosophila homologue dSTIM have been identified as key regulators of store-operated Ca²⁺ entry in cells. STIM proteins function both as molecular sensors of Ca²⁺concentration in the endoplasmic reticulum (ER) and the molecular triggers that activate SOC channels in the plasma membrane. Ca²⁺ is a crucial intracellular messenger utilised in many cellular processes, and regulators of Ca²⁺ homeostasis in the ER and cytosol are likely to play important roles in developmental processes. STIM protein expression is altered in several tumour types but the role of these proteins in developmental signalling pathways has not been thoroughly examined.

Results

We have investigated the expression and developmental function of dSTIM in Drosophila and shown that dSTIM is widely expressed in embryonic and larval tissues. Using the UAS-Gal4 induction system, we have expressed full-length dSTIM protein and a dsRNAi construct in different tissues. We demonstrate an essential role for dSTIM in larval development and survival, and a tissue-specific role in specification of mechanosensory bristles in the notum and specification of wing vein thickness.

Conclusion

Our studies show that dSTIM regulates growth and patterning of imaginal discs and indicate potential interactions with the Notch and Wingless signaling pathways. These interactions may be relevant to studies implicating STIM family proteins in tumorigenesis.