This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Batista, W. L. Articles by Puccia, R. Search for Related Content PubMed PubMed Citation Articles by Batista, W. L. Articles by Puccia, R.

 Previous Article  |  Next Article 

Eukaryotic Cell, February 2006, p. 379-390, Vol. 5, No. 2
1535-9778/06/$08.00+0     doi:10.1128/EC.5.2.379-390.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

The PbMDJ1 Gene Belongs to a Conserved MDJ1/LON Locus in Thermodimorphic Pathogenic Fungi and Encodes a Heat Shock Protein That Localizes to both the Mitochondria and Cell Wall of Paracoccidioides brasiliensis

Wagner L. Batista,¹ Alisson L. Matsuo,¹ Luciane Ganiko,^1, Tânia F. Barros,^1, Thiago R. Veiga,¹ Edna Freymüller,² and Rosana Puccia^1*

Department of Microbiology, Immunology and Parasitology,¹ Center of Electron Microscopy, Federal University of São Paulo, Rua Botucatu 862, 04023-062 São Paulo, SP, Brazil²

Received 30 September 2005/ Accepted 18 November 2005

J-domain (DnaJ) proteins, of the Hsp40 family, are essential cofactors of their cognate Hsp70 chaperones, besides acting as independent chaperones. In the present study, we have demonstrated the presence of Mdj1, a mitochondrial DnaJ member, not only in the mitochondria, where it is apparently sorted, but also in the cell wall of Paracoccidioides brasiliensis, a thermodimorphic pathogenic fungus. The molecule (PbMdj1) was localized to fungal yeast cells using both confocal and electron microscopy and also flow cytometry. The anti-recombinant PbMdj1 antibodies used in the reactions specifically recognized a single 55-kDa mitochondrial and cell wall (alkaline ß-mercaptoethanol extract) component, compatible with the predicted size of the protein devoid of its matrix peptide-targeting signal. Labeling was abundant throughout the cell wall and especially in the budding regions; however, anti-PbMdj1 did not affect fungal growth in the concentrations tested in vitro, possibly due to the poor access of the antibodies to their target in growing cells. Labeled mitochondria stood preferentially close to the plasma membrane, and gold particles were detected in the thin space between them, toward the cell surface. We show that Mdj1 and the mitochondrial proteinase Lon homologues are heat shock proteins in P. brasiliensis and that their gene organizations are conserved among thermodimorphic fungi and Aspergillus, where the genes are adjacent and have a common 5' region. This is the first time a DnaJ member has been observed on the cell surface, where its function is speculative.

Present address: University of Texas at El Paso, El Paso, Tex.

Present address: Department of Clinical and Toxicological Analyses, Federal University of Bahia, Bahia, BA, Brazil.

This article has been cited by other articles:

• Rodrigues, M. L., Nakayasu, E. S., Oliveira, D. L., Nimrichter, L., Nosanchuk, J. D., Almeida, I. C., Casadevall, A. (2008). Extracellular Vesicles Produced by Cryptococcus neoformans Contain Protein Components Associated with Virulence. Eukaryot Cell 7: 58-67 [Abstract] [Full Text]