Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/27/2005
Publication Date: 7/13/2005
Citation: Uthe, J.J., Zhao, S., Tuggle, C.K., Bearson, S.M. 2005. Differential expression of porcine cytoskeleton genes during infection with Salmonella enterica serotype Choleraesuis [abstract]. Genetics of Animal Health. p. 128.
Technical Abstract: As a facultative intracellular pathogen, Salmonella facilitates its own internalization by using effector proteins from the Type III secretion system (TTSS) to manipulate the host’s actin cytoskeleton. During an investigation of the porcine response to inoculation with Salmonella enterica serotype Choleraesuis, three cytoskeleton-associated factors were identified as exhibiting altered gene expression profiles in the mesenteric lymph nodes over a three-week period. The expression of Syntenin, involved in actin cytoskeleton rearrangements, was significantly increased 2 days post infection (d p.i.). Thymosin-beta-4, a suppressor of actin nucleation, was down-regulated at 1 d and 21 d p.i. The expression of Arp2/3 complex subunit 2, essential in facilitating the growth of branched actin filaments, was decreased at 7 d and 21 d p.i. Although it has been suggested that activation of the Arp2/3 complex via Rho GTPases Cdc42 and Rac is important for actin assembly during Salmonella invasion, others have shown that Salmonella also possesses a mechanism to polymerize actin independently from the Arp2/3 complex. Thus, down-regulation of Arp2/3 complex subunit 2 in this study may indicate that host-adapted S. Choleraesuis nucleates actin polymerization directly through bacterial actin binding protein(s) of the TTSS (such as SipA and SipC) rather than via the Arp2/3 complex.