Caenopores are antimicrobial and pore-forming polypeptides in Caenorhabditis elegans belonging to the saposin-like protein superfamily and are considered important elements of the nematode's intestinal immune system. In the present study, we demonstrate that, unlike the other members of the multifarious gene family (spps) coding for caenopores, spp-12 is expressed exclusively in two pharyngeal neurons. Recombinantly expressed SPP-12 binds to phospholipid membranes and forms pores in a pH-dependent manner characteristic of caenopores. Moreover, SPP-12 kills viable Gram-positive bacteria, yeast cells and amoebae by permeabilizing their membranes, suggesting a wide-target cell spectrum. A spp-12 knockout mutant is more susceptible to pathogenic Bacillus thuringiensis than wild-type worms and is tolerant to non-pathogenic bacteria. By contrast, SPP-1, a caenopore, whose gene is expressed only in the intestine and reported to be regulated by the same pathway as spp-12, is apparently non-protective against pathogenic B. thuringiensis, although it also does display antimicrobial activity. The transcription of spp-1 is down-regulated in wild-type worms in the presence of pathogenic B. thuringiensis and a spp-1 knockout mutant is hyposusceptible to this bacterium. This implies that SPP-12, but not SPP-1, contributes to resistance against B. thuringiensis, a natural pathogen of the nematode.
Skip Nav Destination
Article navigation
July 2012
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkEditorial Board
Research Article|
June 27 2012
The saposin-like protein SPP-12 is an antimicrobial polypeptide in the pharyngeal neurons of Caenorhabditis elegans and participates in defence against a natural bacterial pathogen
Aylin Hoeckendorf;
Aylin Hoeckendorf
1Zoological Institute, Zoophysiology, University of Kiel, Olshausenstrasse 40, 24098 Kiel, Germany
Search for other works by this author on:
Mareike Stanisak;
Mareike Stanisak
1Zoological Institute, Zoophysiology, University of Kiel, Olshausenstrasse 40, 24098 Kiel, Germany
Search for other works by this author on:
Matthias Leippe
Matthias Leippe
1
1Zoological Institute, Zoophysiology, University of Kiel, Olshausenstrasse 40, 24098 Kiel, Germany
1To whom correspondence should be addressed (email mleippe@zoologie.uni-kiel.de).
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
November 30 2011
Revision Received:
April 05 2012
Accepted:
April 23 2012
Accepted Manuscript online:
April 23 2012
Online ISSN: 1470-8728
Print ISSN: 0264-6021
© The Authors Journal compilation © 2012 Biochemical Society
2012
Biochem J (2012) 445 (2): 205–212.
Article history
Received:
November 30 2011
Revision Received:
April 05 2012
Accepted:
April 23 2012
Accepted Manuscript online:
April 23 2012
Citation
Aylin Hoeckendorf, Mareike Stanisak, Matthias Leippe; The saposin-like protein SPP-12 is an antimicrobial polypeptide in the pharyngeal neurons of Caenorhabditis elegans and participates in defence against a natural bacterial pathogen. Biochem J 15 July 2012; 445 (2): 205–212. doi: https://doi.org/10.1042/BJ20112102
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.