title: Chlamydia trachomatis inclusion membrane protein CT850 interacts with the dynein light chain DYNLT1 (Tctex1).
abstract: Chlamydia trachomatis actively subverts the minus-end directed microtubule motor, dynein, to traffic along microtubule tracks to the Microtubule Organizing Center (MTOC) where it remains within a membrane bound replicative vacuole for the duration of its intracellular development. Unlike most substrates of the dynein motor, disruption of the dynactin cargo-linking complex by over-expression of the p50 dynamitin subunit does not inhibit C. trachomatis transport. A requirement for chlamydial protein synthesis to initiate this process suggests that a chlamydial product supersedes a requirement for p50 dynamitin. A yeast 2-hybrid system was used to screen the chlamydia inclusion membrane protein CT850 against a HeLa cell cDNA library and identified an interaction with the dynein light chain DYNLT1 (Tctex1). This interaction was at least partially dependent upon an (R/K-R/K-X-X-R/K) motif that is characteristic of DYNLT1 binding domains. CT850 expressed ectopically in HeLa cells localized at the MTOC and this localization is similarly dependent upon the predicted DYNLT1 binding domain. Furthermore, DYNLT1 is enriched at focal concentrations of CT850 on the chlamydial inclusion membrane that are known to interact with dynein and microtubules. Depletion of DYNLT1 disrupts the characteristic association of the inclusion membrane with centrosomes. Collectively, the results suggest that CT850 interacts with DYNLT1 to promote appropriate positioning of the inclusion at the MTOC.
authors.affiliation: Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA; Quinnipiac University, Hamden, CT 06518, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Mital
authors.affiliation: Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA.
authors.forename: Erika I
authors.initials: EI
authors.lastname: Lutter
authors.affiliation: Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA.
authors.forename: Alexandra C
authors.initials: AC
authors.lastname: Barger
authors.affiliation: Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA.
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Dooley
authors.affiliation: Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA. Electronic address: Ted_Hackstadt@NIH.Gov.
authors.forename: Ted
authors.initials: T
authors.lastname: Hackstadt
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002692:Chlamydia trachomatis / Q000235:genetics / Q000378:metabolism*; D004398:Dyneins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D006367:HeLa Cells; D054884:Host-Pathogen Interactions; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D022101:Microtubule-Organizing Center / Q000378:metabolism; D054730:Protein Interaction Domains and Motifs; D034741:RNA, Small Interfering / Q000235:genetics; D020798:Two-Hybrid System Techniques
chemical_list: D001426:Bacterial Proteins; C533376:DYNLT1 protein, human; D008565:Membrane Proteins; D034741:RNA, Small Interfering; D004398:Dyneins
keywords: Chlamydia; Dynein; Microtubules; Vesicle trafficking