Altered hepatic localization and expression of XXXX after common bile duct ligation.

@entity35 @entity10261 @entity23818 @entity659
Epithelial tight junctions form a regulated barrier that seals the paracellular space and prevents mixing of luminal contents with the interstitium. This barrier is composed of a group of proteins including the putative "sealing" protein @entity659 that appears to bind directly to a cytoplasmic junction protein, @entity10261 . To study the interaction and regulation of these two components when paracellular integrity is altered, we assessed protein expression and immunofluorescent (IF) localization of @entity10261 and @entity659 in a @entity35 model of hepatocyte tight junction damage induced by common bile duct ligation (CBDL). Protein levels were detected in liver by immunoblotting and IF localization by 3-dimensional reconstruction of serial 0.5-micron confocal microscopic optical sections. As previously described, @entity10261 protein levels progressively increased to threefold control levels 9 days after CBDL. In contrast, @entity659 protein levels decreased by 50% within 2 days after CBDL and returned to control values by 9 days. In control IF sections, @entity23818 colocalized, forming thin continuous staining outlining canaliculi. After CBDL, @entity10261 staining appeared discontinuous, and a punctate pericanalicular accumulation of signal developed around junctional areas. @entity659 staining was also discontinuous after CBDL, but, in contrast to @entity10261 , was not punctate and remained localized either in a linear fashion along canalicular margins or in a homogeneous fashion in immediately surrounding areas. CBDL results in changes in the expression and localization of the putative tight junction sealing protein @entity659 in hepatocytes that are distinct from those observed for the peripheral membrane tight junction protein @entity10261 .(ABSTRACT TRUNCATED AT 250 WORDS)
