These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: A new regulatory mechanism of NF-kappaB activation by I-kappaBbeta in cancer cells.
    Author: Kim JM, Voll RE, Ko C, Kim DS, Park KS, Kim SY.
    Journal: J Mol Biol; 2008 Dec 26; 384(4):756-65. PubMed ID: 18950638.
    Abstract:
    Transglutaminase 2 (TGase 2) catalyzes covalent isopeptide bond formation between glutamine and lysine residues. Recently, we reported that TGase 2 activates nuclear factor-kappa B (NF-kappaB) by depleting inhibitor of NF-kappaBalpha (I-kappaBalpha) levels via polymer formation. Furthermore, TGase 2 expression synergistically increases NF-kappaB activity with canonical pathway. The major I-kappaB proteins such as I-kappaBalpha and I-kappaBbeta resemble each other in both primary sequence and tertiary structure. However, I-kappaBbeta does not degrade fully, while I-kappaBalpha degrades immediately in response to most stimuli. We found that I-kappaBbeta does not contain any of the previously identified TGase 2 target sites. In this study, both an in vitro cross-linking assay and a TGase 2 transfection assay revealed that I-kappaBbeta is independent from TGase 2-mediated polymerization. Furthermore, increased I-kappaBbeta expression reversed NF-kappaB activation in cancer cells, compensating for the loss of I-kappaBalpha via TGase 2 polymerization.
    [Abstract] [Full Text] [Related] [New Search]