Journal Article

Drosophila RalA is essential for the maintenance of Jak/Stat signalling in ovarian follicles

Devergne, Olivier, Cerezo, Delphine, Ghiglione, Christian, Noselli, Stéphane

2008

Overview

Small GTPases of the Ras‐like (Ral) family are crucial for signalling functions in both normal and cancer cells; however, their role in a developing organism is poorly understood. Here, we identify the Drosophila Ral homologue RalA as a new key regulator of polar‐cell differentiation during oogenesis. Polar cells have a crucial role in patterning the egg chamber and in recruiting border cells, which undergo collective and guided migration. We show that RalA function is essential for the maintenance of anterior and posterior polar‐cell fate and survival. RalA is required cell autonomously to control the expression of polar‐cell‐specific markers, including the Jak/Stat ligand Unpaired. The loss of RalA also causes a cell non‐autonomous phenotype owing to reduced Jak/Stat signalling in neighbouring follicle cells. As a result, border‐cell assembly and migration as well as the polarization of the oocyte are defective. Thus, RalA is required in organizing centres to control proper patterning and migration in vivo .

• Publisher: John Wiley & Sons, Ltd,Nature Publishing Group UK,Springer Nature B.V,EMBO Press,Nature Publishing Group
• Subject: Animals / border cell / Cell adhesion & migration / Cell Differentiation / Cell Movement / Cell Polarity / Development Biology / Drosophila / Drosophila melanogaster - cytology / Drosophila melanogaster - enzymology / Drosophila Proteins - metabolism / EMBO11 / Female / Genotype & phenotype / Insects / Jak/Stat / Janus Kinases - metabolism / Life Sciences / Molecular biology / Monomeric GTP-Binding Proteins - metabolism / Mutation - genetics / Ovarian Follicle - cytology / Ovarian Follicle - enzymology / polar cell / Protein Transport / RalA / Scientific Report / Signal Transduction / STAT Transcription Factors - metabolism / Subcellular Fractions - metabolism