A conserved metalloprotease mediates ecdysis in Caenorhabditis elegans

Davis, M.W., Birnie, A.J., Chan, A.C., Page, A.P. and Jorgensen, A.M. (2004) A conserved metalloprotease mediates ecdysis in Caenorhabditis elegans. Development, 131, pp. 6001-6008. (doi: 10.1242/dev.01454)

Abstract

Molting is required for progression between larval stages in the life cycle of nematodes. We have identified four mutant alleles of a <i>Caenorhabditis elegans</i> metalloprotease gene, <i>nas-37</i>, that cause incomplete ecdysis. At each molt the cuticle fails to open sufficiently at the anterior end and the partially shed cuticle is dragged behind the animal. The gene is expressed in hypodermal cells 4 hours before ecdysis during all larval stages. The <i>NAS-37</i> protein accumulates in the anterior cuticle and is shed in the cuticle after ecdysis. This pattern of protein accumulation places NAS- 37 in the right place and at the right time to degrade the cuticle to facilitate ecdysis. The nas-37 gene has orthologs in other nematode species, including parasitic nematodes, and they undergo a similar shedding process. For example, <i>Haemonchus contortus</i> molts by digesting a ring of cuticle at the tip of the nose. Incubating <i>Haemonchus</i> larvae in extracted exsheathing fluids causes a refractile ring of digested cuticle to form at the tip of the nose. When <i>Haemonchus</i> cuticles are incubated with purified NAS-37, a similar refractile ring forms. NAS-37 degradation of the <i>Haemonchus</i> cuticle suggests that the metalloproteases and the cuticle substrates involved in exsheathment of parasitic nematodes are conserved in free-living nematodes.

• Item Type: Articles
• Keywords: Astacin, caenorhabditis elegans, cuticle, metalloprotease, molting.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Page, Professor Tony
• Authors: Davis, M.W., Birnie, A.J., Chan, A.C., Page, A.P., and Jorgensen, A.M.
• Subjects: Q Science > QH Natural history > QH345 Biochemistry; Q Science > QH Natural history > QH301 Biology; Q Science > QH Natural history > QH426 Genetics
• College/School: College of Medical Veterinary and Life Sciences; College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Development
• Publisher: Company of Biologists
• ISSN: 0950-1991
• Copyright Holders: Copyright © 2004 Company of Biologists
• First Published: First published in Development 131:6001-6008
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher