Torso-like mediates extracellular accumulation of Furin-cleaved Trunk to pattern the Drosophila embryo termini.
Patterning of the Drosophila embryonic termini is achieved by localized activation of the Torso receptor by the growth factor Trunk. Governing this event is the perforin-like protein Torso-like, which is localized to the extracellular space at the embryo poles and has long been proposed to control localized proteolytic activation of Trunk. However, a protease involved in terminal patterning remains to be identified, and the role of Torso-like remains unknown. Here we find that Trunk is cleaved intracellularly by Furin proteases. We further show that Trunk is secreted, and that levels of extracellular Trunk are greatly reduced in torso-like null mutants. On the basis of these and previous findings, we suggest that Torso-like functions to mediate secretion of Trunk, thus providing the mechanism for spatially restricted activation of Torso. Our data represent an alternative mechanism for the spatial control of receptor signalling, and define a different role for perforin-like proteins in eukaryotes.
School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia.|Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.|Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.
Travis K
TK
Johnson
School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia.|Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.|Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.
Michelle A
MA
Henstridge
School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia.|Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.|Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.
Anabel
A
Herr
School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia.|Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.|Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.
Karyn A
KA
Moore
Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.|Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.
James C
JC
Whisstock
School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia.
Coral G
CG
Warr
D000818:Animals; D019521:Body Patterning; D004330:Drosophila / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D045683:Furin / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D008297:Male; D015398:Signal Transduction
D029721:Drosophila Proteins; C096356:trk protein, Drosophila; C085211:tsl protein, Drosophila; C079637:Fur1 protein, Drosophila; C000607566:Fur2 protein, Drosophila; D045683:Furin