Journal
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Volume 375, Issue 2, Pages 215-219Publisher
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.bbrc.2008.07.162
Keywords
alveolata; plastid; trophozoites; vacuole; zoospore
Categories
Funding
- National Science Foundation [1013 06 16409]
- NOAA [NA90AA-D-SGO63]
Ask authors/readers for more resources
Perkinsus marinus (Phylum Perkinsozoa), a protozoan parasite of oysters, is considered one of the earliest diverging groups of the lineage leading to dinoflagellates. Perkinsus trophozoites are phagocytosed by oyster hemocytes, where they are likely exposed to reactive oxygen species. As part of its reactive oxygen detoxifying pathway, P. marinus possesses two iron-cofactored Sol) (PmSOD1 and PmSOD2). Immunoflourescence analysis of P. marinus trophozoites and gene complementation in yeast revealed that PmSOD1 is targeted to the mitochondria. Surprisingly, although PmSOD2 is characterized by a bipartite N-terminus extension typical of plastid targeting, in preliminary immunofluorescence studies it was Visualized as punctuate regions in the cytoplasm that Could not be assigned to any organelle. Here, we used immunogold electron microscopy to examine the subcellular localization PmSOD2 in P. marinus trophozoites. Gold grains were mostly associated with single-membrane vesicle-like Structures, and eventually, localized to electron-dense, apparently amorphous material present in the lumen of a larger, unique compartment. The images Suggested that PmSOD2 is targeted to small vesicles that fuse and/or discharge their content into a larger compartment, possibly the large vacuole typical of the mature trophozoites. In light of the in silico targeting prediction, the association of PmSOD2 with single-membrane compartments raises interesting questions regarding its organellar targeting, and the nature of a putative relic plastid in Perkinsus species. (c) 2008 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available