TY - JOUR
T1 - Domain analyses reveal that chlamydia trachomatis CT694 protein belongs to the membrane-localized family of type III effector proteins
AU - Bullock, Holly D.
AU - Hower, Suzanne
AU - Fields, Kenneth A.
PY - 2012/8/10
Y1 - 2012/8/10
N2 - The Chlamydia trachomatis type three-secreted effector protein CT694 is expressed during late-cycle development yet is secreted by infectious particles during the invasion process. We have previously described the presence of at least two functional domains within CT694. CT694 was found to interact with the human protein Ahnak through a C-terminal domain and affect formation of host-cell actin stress fibers. Immunolocalization analyses of ectopically expressed pEGFP-CT694 also revealed plasma membrane localization for CT694 that was independent of Ahnak binding. Here we provide evidence that CT694 contains multiple functional domains. Plasma membrane localization and CT694-induced alterations in host cell morphology are dependent on an N-terminal domain. We demonstrate that membrane association of CT694 is dependent on a domain resembling a membrane localization domain (MLD) found in anti-host proteins from Yersinia, Pseudomonas, and Salmonella spp. This domain is necessary and sufficient for localization and morphology changes but is not required for Ahnak binding. Further, the CT694 MLD is able to complement ExoS ΔMLD when ectopically expressed. Taken together, our data indicate that CT694 is a multidomain protein with the potential to modulate multiple host cell processes.
AB - The Chlamydia trachomatis type three-secreted effector protein CT694 is expressed during late-cycle development yet is secreted by infectious particles during the invasion process. We have previously described the presence of at least two functional domains within CT694. CT694 was found to interact with the human protein Ahnak through a C-terminal domain and affect formation of host-cell actin stress fibers. Immunolocalization analyses of ectopically expressed pEGFP-CT694 also revealed plasma membrane localization for CT694 that was independent of Ahnak binding. Here we provide evidence that CT694 contains multiple functional domains. Plasma membrane localization and CT694-induced alterations in host cell morphology are dependent on an N-terminal domain. We demonstrate that membrane association of CT694 is dependent on a domain resembling a membrane localization domain (MLD) found in anti-host proteins from Yersinia, Pseudomonas, and Salmonella spp. This domain is necessary and sufficient for localization and morphology changes but is not required for Ahnak binding. Further, the CT694 MLD is able to complement ExoS ΔMLD when ectopically expressed. Taken together, our data indicate that CT694 is a multidomain protein with the potential to modulate multiple host cell processes.
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U2 - 10.1074/jbc.M112.386904
DO - 10.1074/jbc.M112.386904
M3 - Article
C2 - 22711538
AN - SCOPUS:84865015973
SN - 0021-9258
VL - 287
SP - 28078
EP - 28086
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 33
ER -