Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.
Subscribe

Logo for

Science 317 (5838): 678-681

Copyright © 2007 by the American Association for the Advancement of Science

Immune-like Phagocyte Activity in the Social Amoeba

Guokai Chen,1* Olga Zhuchenko,1* Adam Kuspa1,2,3{dagger}

Abstract: Social amoebae feed on bacteria in the soil but aggregate when starved to form a migrating slug. We describe a previously unknown cell type in the social amoeba, which appears to provide detoxification and immune-like functions and which we term sentinel (S) cells. S cells were observed to engulf bacteria and sequester toxins while circulating within the slug, eventually being sloughed off. A Toll/interleukin-1 receptor (TIR) domain protein, TirA, was also required for some S cell functions and for vegetative amoebae to feed on live bacteria. This apparent innate immune function in social amoebae, and the use of TirA for bacterial feeding, suggest an ancient cellular foraging mechanism that may have been adapted to defense functions well before the diversification of the animals.

1 Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
2 Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
3 Program in Developmental Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.

* These authors contributed equally to this work.

{dagger} To whom correspondence should be addressed. E-mail: akuspa{at}bcm.tmc.edu

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
The Nramp (Slc11) proteins regulate development, resistance to pathogenic bacteria and iron homeostasis in Dictyostelium discoideum.
B. Peracino, S. Buracco, and S. Bozzaro (2013)
J. Cell Sci. 126, 301-311
   Abstract »    Full Text »    PDF »
Evolution of cooperation and control of cheating in a social microbe.
J. E. Strassmann and D. C. Queller (2011)
PNAS 108, 10855-10862
   Abstract »    Full Text »    PDF »
Characterization of the Dictyostelium Homolog of Chromatin Binding Protein DET1 Suggests a Conserved Pathway Regulating Cell Type Specification and Developmental Plasticity.
M. J. Dubin, S. Kasten, and W. Nellen (2011)
Eukaryot. Cell 10, 352-362
   Abstract »    Full Text »    PDF »
Phosphoinositides differentially regulate bacterial uptake and Nramp1-induced resistance to Legionella infection in Dictyostelium.
B. Peracino, A. Balest, and S. Bozzaro (2010)
J. Cell Sci. 123, 4039-4051
   Abstract »    Full Text »    PDF »
Dictyostelium possesses highly diverged presenilin/{gamma}-secretase that regulates growth and cell-fate specification and can accurately process human APP: a system for functional studies of the presenilin/{gamma}-secretase complex.
V. C. McMains, M. Myre, L. Kreppel, and A. R. Kimmel (2010)
Dis. Model. Mech. 3, 581-594
   Abstract »    Full Text »    PDF »
Dictyostelium Finds New Roles to Model.
J. G. Williams (2010)
Genetics 185, 717-726
   Abstract »    Full Text »    PDF »
Infection by Tubercular Mycobacteria Is Spread by Nonlytic Ejection from Their Amoeba Hosts.
M. Hagedorn, K. H. Rohde, D. G. Russell, and T. Soldati (2009)
Science 323, 1729-1733
   Abstract »    Full Text »    PDF »

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882