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Spivey VL, Molle V, Whalan RH, Rodgers A, Leiba J, Stach L, Walker KB, Smerdon SJ, Buxton RS. Forkhead-associated (FHA) domain containing ABC transporter Rv1747 is positively regulated by Ser/Thr phosphorylation in Mycobacterium tuberculosis. J Biol Chem 2011; 286:26198-209. [PMID: 21622570 PMCID: PMC3138270 DOI: 10.1074/jbc.m111.246132] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 05/24/2011] [Indexed: 12/22/2022] Open
Abstract
One major signaling method employed by Mycobacterium tuberculosis, the causative agent of tuberculosis, is through reversible phosphorylation of proteins mediated by protein kinases and phosphatases. This study concerns one of these enzymes, the serine/threonine protein kinase PknF, that is encoded in an operon with Rv1747, an ABC transporter that is necessary for growth of M. tuberculosis in vivo and contains two forkhead-associated (FHA) domains. FHA domains are phosphopeptide recognition motifs that specifically recognize phosphothreonine-containing epitopes. Experiments to determine how PknF regulates the function of Rv1747 demonstrated that phosphorylation occurs on two specific threonine residues, Thr-150 and Thr-208. To determine the in vivo consequences of phosphorylation, infection experiments were performed in bone marrow-derived macrophages and in mice using threonine-to-alanine mutants of Rv1747 that prevent specific phosphorylation and revealed that phosphorylation positively modulates Rv1747 function in vivo. The role of the FHA domains in this regulation was further demonstrated by isothermal titration calorimetry, using peptides containing both phosphothreonine residues. FHA-1 domain mutation resulted in attenuation in macrophages highlighting the critical role of this domain in Rv1747 function. A mutant deleted for pknF did not, however, have a growth phenotype in an infection, suggesting that other kinases can fulfill its role when it is absent. This study provides the first information on the molecular mechanism(s) regulating Rv1747 through PknF-dependent phosphorylation but also indicates that phosphorylation activates Rv1747, which may have important consequences in regulating growth of M. tuberculosis.
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Affiliation(s)
- Vicky L. Spivey
- From the Division of Mycobacterial Research, Medical Research Council National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom
| | - Virginie Molle
- the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS, UMR 5235, Case 107, Place Eugène Bataillon, 34095 Montpellier Cedex 05, France
| | - Rachael H. Whalan
- From the Division of Mycobacterial Research, Medical Research Council National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom
| | - Angela Rodgers
- the Immunology and Cellular Immunity Section, Bacteriology Division, National Institute of Biological Standards and Control (A Centre of the Health Protection Agency), Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, United Kingdom, and
| | - Jade Leiba
- the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Universités de Montpellier II et I, CNRS, UMR 5235, Case 107, Place Eugène Bataillon, 34095 Montpellier Cedex 05, France
| | - Lasse Stach
- the Division of Molecular Structure, Medical Research Council National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom
| | - K. Barry Walker
- the Immunology and Cellular Immunity Section, Bacteriology Division, National Institute of Biological Standards and Control (A Centre of the Health Protection Agency), Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, United Kingdom, and
| | - Stephen J. Smerdon
- the Division of Molecular Structure, Medical Research Council National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom
| | - Roger S. Buxton
- From the Division of Mycobacterial Research, Medical Research Council National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom
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Chakraborti PK, Matange N, Nandicoori VK, Singh Y, Tyagi JS, Visweswariah SS. Signalling mechanisms in Mycobacteria. Tuberculosis (Edinb) 2011; 91:432-40. [PMID: 21570916 DOI: 10.1016/j.tube.2011.04.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 03/28/2011] [Accepted: 04/10/2011] [Indexed: 11/18/2022]
Abstract
The importance of inter- and intracellular signal transduction in all forms of life cannot be underestimated. A large number of genes dedicated to cellular signalling are found in almost all sequenced genomes, and Mycobacteria are no exception. What appears to be interesting in Mycobacteria is that well characterized signalling mechanisms used by bacteria, such as the histidine-aspartate phosphorelay seen in two-component systems, are found alongside signalling components that closely mimic those seen in higher eukaryotes. This review will describe the important contribution made by researchers in India towards the identification and characterization of proteins involved in two-component signalling, protein phosphorylation and cyclic nucleotide metabolism.
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