{"id":1807,"date":"2020-06-30T21:06:51","date_gmt":"2020-06-30T13:06:51","guid":{"rendered":"http:\/\/www.bioactivescreeninglibrary.com\/?p=1807"},"modified":"2022-01-07T10:57:39","modified_gmt":"2022-01-07T02:57:39","slug":"previously-egf-induced-activation-p65-p50-forms-heterodimers-identified-promoter-region-ctcf","status":"publish","type":"post","link":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/2020\/06\/30\/previously-egf-induced-activation-p65-p50-forms-heterodimers-identified-promoter-region-ctcf\/","title":{"rendered":"We found previously that EGF-induced activation of p65 and p50 forms heterodimers identified in the promoter region of CTCF"},"content":{"rendered":"

Interaction of Bcl-3 and CTCF gene resulted in suppressing CTCF expression in corneal epithelial cells. As shown above that UV stress-induced Bcl-3 activation downregulated CTCF, we further verified whether altered Bcl-3 activity has a Wortmannin<\/a> functional impact on regulation of CTCF in UV stressinduced HCE cells. Bcl-3 was knocked down by transfecting cells with siRNA specific to Bcl-3, and control cells were transfected with non-related siRNA with\/without UV irradiation. The results showed that knockdown of Bcl-3 resulted in increases in CTCF mRNA levels following a time course detected by RTPCR and by quantitative real-time PCR. In addition, knocking down Bcl-3 mRNA abolished the inhibitory effect of UV irradiation on CTCF promoter activity. The effects of UV irradiation on suppression of CTCF were reversed by silencing Bcl-3 mRNA indicate that Bcl-3 plays an important role in regulating CTCF transcription by control of CTCF promoter activity. Interaction between Bcl-3 and p50. In order to demonstrate the physical interaction between Bcl-3 and p50, Bcl-3 and p50 were pulled down each other by antibodies against Bcl-3 and p50 in EGF- and UV stress-induce cells, respectively. Bcl-3 antibody pulled down more p50 UV stress-induced HCE cell compared with cells stimulated with EGF. No bands were found in the lanes of IgG controls indicating that there was truly a difference of the p50 levels in UV and EGF stimulated cells. In the meantime, Bcl-3 was specifically immuno-coprecipitated with p50 by anti-p50 antibody in UV stress-induced cells. However, Bcl-3 did not interact with p50 in EGF-stimulated cells. Total amounts of p50 and Bcl-3 in cell lysates were analyzed by Western blots for input controls. To further investigate whether there is a functional interaction between Bcl-3 and p50, experiments to co-localize Bcl-3 and p50 in nuclei in EGF and UV stress-induced cells were performed using antibodies labeled with Alexa 488 and 594 against Bcl-3 and p50, respectively. Bcl-3 and p50 were co-localized in the nucleus that was indicated by DAPI staining in UV stress-induced cells. There was no co-localization of Bcl-3 and p50 found in EGFinduced and un-stimulated cells. Further statistical analysis revealed that there was a significant increase in Bcl-3 and p50 co-localization in nuclei of UV stress-induced cells. Immunoco-localization of Bcl-3 and p50 in the nucleus of UV stress-induced cells suggests that Bcl-3 and p50 are very likely to form a functional heterodimer complex in response to UV stress stimulation. The results provide further evidence indicating that Bcl-3 has functional interactions and physical associations with p50 in the nucleus of UV stress-stimulated HCE cells. In recent studies, we demonstrate that regulation of CTCF is stimulus-dependent to affect HCE cell fate. Differential stimuli involve activation of NF-kB subtypes that are able to regulate CTCF activity in the NF-kB family. However, there is no detailed information available regarding why UV stress-induced regulation of CTCF is different from the EGF effect since both stimuli all activate the NF-kB pathway.<\/p>\n","protected":false},"excerpt":{"rendered":"

Interaction of Bcl-3 and CTCF gene resulted in suppressing CTCF expression in corneal epithelial cells. As shown above that UV stress-induced Bcl-3 activation downregulated CTCF, we further verified whether altered Bcl-3 activity has a Wortmannin functional impact on regulation of CTCF in UV stressinduced HCE cells. Bcl-3 was knocked down by transfecting cells with siRNA … Continue reading “We found previously that EGF-induced activation of p65 and p50 forms heterodimers identified in the promoter region of CTCF”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/1807"}],"collection":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/comments?post=1807"}],"version-history":[{"count":1,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/1807\/revisions"}],"predecessor-version":[{"id":1808,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/1807\/revisions\/1808"}],"wp:attachment":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/media?parent=1807"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/categories?post=1807"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/tags?post=1807"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}