TY - JOUR
T1 - Potential involvement of Brugia malayi cysteine proteases in the maintenance of the endosymbiotic relationship with Wolbachia
AU - Lustigman, Sara
AU - Melnikow, Elena
AU - Anand, Setty Balakrishnan
AU - Contreras, Aroha
AU - Nandi, Vijay
AU - Liu, Jing
AU - Bell, Aaron
AU - Unnasch, Thomas R.
AU - Rogers, Mathew B.
AU - Ghedin, Elodie
N1 - Funding Information:
We thank the NIAID/NIH Filariasis Research Reagent Repository Center (www.filariasiscenter.org) for the adult female B. malayi worm supply. We thank Drs. Mark Blaxter and Georgio Koutsovoulos from The University of Edinburgh, UK, for providing us with the putative sequences of the A. viteae CPL family members before they were available on the 959 nematodes website ( http://nematodes.org/genomes/acanthocheilonema_viteae/ ). We thank Dr. Kenneth M. Pfarr, University Clinic Bonn, Germany, for providing us with the cDNA samples used for the analyses of the A. viteae cpl transcripts from female adult worms recovered from infected M. unguiculatus that were treated with tetracycline. We also thank Saheed Bachu for technical assistance. This study was funded by NIAID/NIH Grant No. AI072465 to T.R.U., E.G. and S.L. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. The authors report no conflict of interest.
Publisher Copyright:
© 2014 The Authors.
PY - 2014/12/1
Y1 - 2014/12/1
N2 - Brugia malayi, a parasitic nematode that causes lymphatic filariasis, harbors endosymbiotic intracellular bacteria, Wolbachia, that are required for the development and reproduction of the worm. The essential nature of this endosymbiosis led to the development of anti- Wolbachia chemotherapeutic approaches for the treatment of human filarial infections. Our study is aimed at identifying specific proteins that play a critical role in this endosymbiotic relationship leading to the identification of potential targets in the adult worms. Filarial cysteine proteases are known to be involved in molting and embryogenesis, processes shown to also be Wolbachia dependent. Based on the observation that cysteine protease transcripts are differentially regulated in response to tetracycline treatment, we focused on defining their role in symbiosis. We observe a bimodal regulation pattern of transcripts encoding cysteine proteases when in vitro tetracycline treated worms were examined. Using tetracycline-treated infertile female worms and purified embryos we established that the first peak of the bimodal pattern corresponds to embryonic transcripts while the second takes place within the hypodermis of the adult worms. Localization studies of the native proteins corresponding to Bm-cpl-3 and Bm-cpl-6 indicate that they are present in the area surrounding Wolbachia, and, in some cases, the proteins appear localized within the bacteria. Both proteins were also found in the inner bodies of microfilariae. The possible role of these cysteine proteases during development and endosymbiosis was further characterized using RNAi. Reduction in Bm-cpl-3 and Bm-cpl-6 transcript levels was accompanied by hindered microfilarial development and release, and reduced Wolbachia DNA levels, making these enzymes strong drug target candidates.
AB - Brugia malayi, a parasitic nematode that causes lymphatic filariasis, harbors endosymbiotic intracellular bacteria, Wolbachia, that are required for the development and reproduction of the worm. The essential nature of this endosymbiosis led to the development of anti- Wolbachia chemotherapeutic approaches for the treatment of human filarial infections. Our study is aimed at identifying specific proteins that play a critical role in this endosymbiotic relationship leading to the identification of potential targets in the adult worms. Filarial cysteine proteases are known to be involved in molting and embryogenesis, processes shown to also be Wolbachia dependent. Based on the observation that cysteine protease transcripts are differentially regulated in response to tetracycline treatment, we focused on defining their role in symbiosis. We observe a bimodal regulation pattern of transcripts encoding cysteine proteases when in vitro tetracycline treated worms were examined. Using tetracycline-treated infertile female worms and purified embryos we established that the first peak of the bimodal pattern corresponds to embryonic transcripts while the second takes place within the hypodermis of the adult worms. Localization studies of the native proteins corresponding to Bm-cpl-3 and Bm-cpl-6 indicate that they are present in the area surrounding Wolbachia, and, in some cases, the proteins appear localized within the bacteria. Both proteins were also found in the inner bodies of microfilariae. The possible role of these cysteine proteases during development and endosymbiosis was further characterized using RNAi. Reduction in Bm-cpl-3 and Bm-cpl-6 transcript levels was accompanied by hindered microfilarial development and release, and reduced Wolbachia DNA levels, making these enzymes strong drug target candidates.
KW - Cysteine proteases
KW - Filaria
KW - Symbiosis
KW - Wolbachia
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U2 - 10.1016/j.ijpddr.2014.08.001
DO - 10.1016/j.ijpddr.2014.08.001
M3 - Article
AN - SCOPUS:84916894409
VL - 4
SP - 267
EP - 277
JO - International Journal for Parasitology: Drugs and Drug Resistance
JF - International Journal for Parasitology: Drugs and Drug Resistance
SN - 2211-3207
IS - 3
ER -