Can the secreted cHtrA gain access to host cell ER to regulate host unfolded protein stress responses? What cellular proteins the secreted cHtrA molecules target during chlamydial infection

in the presence or absence of stress stimulation. Efforts are underway to address these questions. Conclusions Secretion of chlamydial proteins into host cells is necessary for chlamydial organisms to establish and complete intracellular growth. Thus, identifying chlamydial proteins secreted into host cell cytoplasm has become a hot subject. Here, we have presented convincing evidence that the chlamydial periplasmic stress response serine protease cHtrA is secreted out of the chlamydial Y-27632 in vivo organisms into both chlamydial inclusion lumen and host cell cytosol. This selleck kinase inhibitor secretion is specific since various other abundant chlamydial periplasmic proteins remained within the organisms. This novel finding suggests that the highly conserved cHtrA, in addition to its role in modifying chlamydial proteins in the periplasmic region, may also target host proteins, which is consistent with the overall concept

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