FIP2, new linker between Rab11 and Rab14 at the chlamydial inclusion membrane.

LEIVA N; CAPMANY A; GAMBARTE J; DAMIANI MT

Potrero de los Funes. San Luis

Congreso; XLVII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2011

SAIB

Chlamydia trachomatis is an obligate intracellular Gram-negative bacterium that modulates relevant eukaryotic trafficking pathways as an adaptive strategy. Chlamydial proteins might be involved in the recruitment of host Rab GTPases to the inclusion. Rabs are the molecules in charge of intracellular traffic control. We showed that Rab11 and Rab14 are required for bacterial nutrition and replication. A recently described eukaryotic protein, FIP2 possesses a Rab Binding Domain (RBD) that interacts with both Rabs. We examined by confocal microscopy the intracellular localization and role of these proteins in Chlamydia-infected cells. FIP2 was recruited to chlamydial inclusions, and colocalized with Rab11 and Rab14 at the inclusion membrane differentially depending on chlamydial developmental cycle stage. FIP2 association to the inclusions was through its RBD domain. Silencing of FIP2 by siRNA reduced Chlamydia trachomatis multiplication, assessed by the counting of inclusion forming units (UFI). Our results demonstrated the requirement of FIP2 for the development and replication of these bacteria. FIP2 might be involved in the formation of macromolecular platforms at the chlamydial inclusion. These data could contribute to the understanding of the complex molecular machinery used by the pathogen to manipulate host trafficking pathways for their own benefit. bacterium that modulates relevant eukaryotic trafficking pathways as an adaptive strategy. Chlamydial proteins might be involved in the recruitment of host Rab GTPases to the inclusion. Rabs are the molecules in charge of intracellular traffic control. We showed that Rab11 and Rab14 are required for bacterial nutrition and replication. A recently described eukaryotic protein, FIP2 possesses a Rab Binding Domain (RBD) that interacts with both Rabs. We examined by confocal microscopy the intracellular localization and role of these proteins in Chlamydia-infected cells. FIP2 was recruited to chlamydial inclusions, and colocalized with Rab11 and Rab14 at the inclusion membrane differentially depending on chlamydial developmental cycle stage. FIP2 association to the inclusions was through its RBD domain. Silencing of FIP2 by siRNA reduced Chlamydia trachomatis multiplication, assessed by the counting of inclusion forming units (UFI). Our results demonstrated the requirement of FIP2 for the development and replication of these bacteria. FIP2 might be involved in the formation of macromolecular platforms at the chlamydial inclusion. These data could contribute to the understanding of the complex molecular machinery used by the pathogen to manipulate host trafficking pathways for their own benefit. bacterium that modulates relevant eukaryotic trafficking pathways as an adaptive strategy. Chlamydial proteins might be involved in the recruitment of host Rab GTPases to the inclusion. Rabs are the molecules in charge of intracellular traffic control. We showed that Rab11 and Rab14 are required for bacterial nutrition and replication. A recently described eukaryotic protein, FIP2 possesses a Rab Binding Domain (RBD) that interacts with both Rabs. We examined by confocal microscopy the intracellular localization and role of these proteins in Chlamydia-infected cells. FIP2 was recruited to chlamydial inclusions, and colocalized with Rab11 and Rab14 at the inclusion membrane differentially depending on chlamydial developmental cycle stage. FIP2 association to the inclusions was through its RBD domain. Silencing of FIP2 by siRNA reduced Chlamydia trachomatis multiplication, assessed by the counting of inclusion forming units (UFI). Our results demonstrated the requirement of FIP2 for the development and replication of these bacteria. FIP2 might be involved in the formation of macromolecular platforms at the chlamydial inclusion. These data could contribute to the understanding of the complex molecular machinery used by the pathogen to manipulate host trafficking pathways for their own benefit.