Chapter 20 Notes: Phenotypic Evolution: Figure WN20.6 - A comparison of the insulin/IGF signaling pathways in Caenorhabditis elegans (A) and Drosophila melanogaster (B).

Figure WN20.6 - A comparison of the insulin/IGF signaling pathways in Caenorhabditis elegans (A) and Drosophila melanogaster (B).

Figure WN20.6. A comparison of the insulin/IGF signaling pathways in Caenorhabditis elegans (A) and Drosophila melanogaster (B). In C. elegans, DAF-2 is the only receptor for insulin-like molecules. Its main effect is to inactivate the DAF-16 transcription factor by phosphorylation, thereby suppressing reproduction and leading to formation of hardy dauer larvae. In the homologous Drosophila pathway, Inr is a receptor for insulin-like peptides. This activates the signaling pathway, leading to increased growth and reproduction at the cost of reduced life span. Key: AAP-1, age-1-associated protein; DAF, dauer larva formation abnormal; IGF, insulin-like growth factor; Inr, insulin receptor; PDK-1, 3-phosphoinositide-dependent kinase 1; PI3K, phosphatidylinositol-3-kinase; PtdIns(4,5)P2, phosphatidylinositol 4,5-biphosphate; PtdIns(3,4,5)P3, phosphatidylinositol 3,4,5-triphosphate. (Redrawn from Fig. 3 in Partridge and Gems 2002.)

The reproduction, modification, storage in a retrieval system, or retransmission, in any form or by any means, electronic, mechanical, or otherwise, for reasons other than personal, noncommercial use is strictly prohibited without prior written permission. You are authorized to download one copy of the material on this Web site for personal, noncommercial use only. The material made available on this Web site is protected by United States copyright laws and is provided solely for the use of instructors in teaching their courses and assessing student learning. Dissemination or sale of any of this material, as a whole or in parts (including on the World Wide Web), is not permitted. All users of these materials and visitors to this Web site are expected to abide by these restrictions. Requests for permission for other uses of this material should be directed to Cold Spring Harbor Laboratory Press, 1 Bungtown Road, Cold Spring Harbor, NY 11724 or submitted via our World Wide Web Site at http://www.cshlpress.com/.