The ten Ingenuity Pathway Analysis (IPA) functional groups with the most differentially expressed genes and the Gene Ontology categories with the lowest P-values are summarised in Additional File 1 Tables S1 and S2. Of the genes that were differentially expressed in response to L. plantarum MB452, 19 were involved in tight Smad2 signaling junction formation (Table 1). Analysis of KEGG pathways using EASE showed that the tight junction pathway was one of four pathways that was enriched
with differentially expressed genes (P and global FDR < 0.05; Additional File 1 Table S3). The molecular interactions between these genes were visualised in an IPA network diagram (Figure 3). The nodes with the most interactions are those that represent the genes for occludin, ZO-1, ZO-2 and cingulin. Table 1 Caco-2
cell genes involved in intracellular junction complex formation that were differentially expressed in the microarray analysis after co-culturing with L. plantarum MB452 (OD600 nm 0.9) for 10 hours. Gene Name Symbol Refseq find more ID Fold Change Moderated Description of role in relation to tight junctions Trk receptor inhibitor & ALK inhibitor occludin OCLN NM_002538 1.39 0.004 tight junction bridging protein vascular endothelial growth factor A VEGFA NM_001025366 1.39 0.002 cytokine that indirectly regulates tight junction formation and strengthening actin beta ACTB NM_001101 1.33 0.005 structural constituent of cytoskeleton cingulin CGN NM_020770 1.29 0.024 tight junction plaque protein associated with occludin par-6 partitioning defective 6 homolog beta PARD6B NM_032521 1.27 0.009 tight junction
plaque protein associated with claudins and involved in cell polarization actin alpha cardiac muscle 1 ACTC1 NM_005159 1.25 0.015 structural constituent of cytoskeleton itchy homolog E3 ubiquitin protein ligase ITCH NM_031483 1.25 0.011 ubiquitin-ligase molecule that regulates occludin degradation junction plakoglobin JUP NM_002230 1.24 0.010 major cytoplasmic protein that forms a complex with cadherins CNKSR family member 3 CNKSR3 NM_173515 1.24 0.006 tight junction plaque protein associated with JAMs snail homolog 1 SNAI1 NM_005985 1.24 0.033 intracellular component that indirectly inhibits occuldin production hepatocyte nuclear factor 4 alpha HNF4A NM_178849 1.24 0.021 transcription regulator that acts on occuldin zona occludens 1 (tight DNA ligase junction protein 1) ZO-1 NM_003257 1.23 0.013 tight junction plaque protein associated with occludin, JAMs and claudins zona occludens 2 (tight junction protein 2) ZO-2 NM_004817 1.23 0.054 tight junction plaque protein associated with occludin and claudins that acts as a guanylate kinase and also found in the nucleus CD2-associated protein CD2AP NM_012120 1.22 0.012 scaffolding molecule that regulates the actin cytoskeleton vinculin VCL NM_003373 1.22 0.027 cytoskeletal protein membrane associated guanylate kinase 3 MAGI-3 NM_152900 1.21 0.