Localisation of the human hSuv3p helicase in the mitochondrial matrix and its preferential unwinding of dsDNA

Minczuk, M. et al. (2002) Localisation of the human hSuv3p helicase in the mitochondrial matrix and its preferential unwinding of dsDNA. Nucleic Acids Research, 30(23), pp. 5074-5086. (doi: 10.1093/nar/gkf647)

Abstract

We characterised the human hSuv3p protein belonging to the family of NTPases/helicases. In yeast mitochondria the hSUV3 orthologue is a component of the degradosome complex and participates in mtRNA turnover and processing, while in Caenorhabditis elegans the hSUV3 orthologue is necessary for viability of early embryos. Using immunofluorescence analysis, an in vitro mitochondrial uptake assay and sub‐fractionation of human mitochondria we show hSuv3p to be a soluble protein localised in the mitochondrial matrix. We expressed and purified recombinant hSuv3p protein from a bacterial expression system. The purified enzyme was capable of hydrolysing ATP with a Km of 41.9 µM and the activity was only modestly stimulated by polynucleotides. hSuv3p unwound partly hybridised dsRNA and dsDNA structures with a very strong preference for the latter. The presented analysis of the hSuv3p NTPase/helicase suggests that new functions of the protein have been acquired in the course of evolution.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Tokatlidis, Professor Kostas
• Authors: Minczuk, M., Piwowarski, J., Papworth, M.A., Awiszus, K., Schalinski, S., Dziembowski, A., Dmochowska, A., Bartnik, E., Tokatlidis, K., Stepien, P.P., and Borowski, P.
• College/School: College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Journal Name: Nucleic Acids Research
• Publisher: Oxford University Press
• ISSN: 0305-1048
• ISSN (Online): 1362-4962
• Copyright Holders: Copyright © 2002 Oxford University Press
• First Published: First published in Nucleic Acids Research 30(23):5074-5086
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher