title: Differential incorporation of biotinylated polyamines by transglutaminase 2.
abstract: Polyamine incorporation or cross-linking of proteins, post-translational modifications mediated by transglutaminase 2 (TGase 2), have been implicated in a variety of physiological functions including cell adhesion, extracellular matrix formation and apoptosis. To better understand the intracellular regulation mechanism of TGase 2, the properties of biotinylated polyamines as substrates for determining in situ TGase activity were analyzed. We synthesized biotinylated spermine (BS), and compared the in vitro and in situ incorporation of BS with that of biotinylated pentylamine (BP), which is an artificial polyamine derivative. When measured in vitro, BP showed a significantly higher incorporation rate than BS. In contrast, in situ incorporation of both BS and BP was not detected even in TGase 2-overexpressed 293 cells. Cells exposed to high calcium showed a marked increase of BP incorporation but not of BS. These data indicate that the in situ activity of TGase 2 gives different results with different substrates, and suggest the possibility of overrepresentation of in situ TGase 2 activity when assayed with BP. Therefore, careful interpretation or evaluation of in situ TGase 2 activity may be required.
authors.affiliation: Department of Biochemistry and Molecular Biology/Aging and Apoptosis Research Center (AARC), Seoul National University College of Medicine, 28 Yongon Dong, Chongno Gu, Seoul 110-799, South Korea.
authors.forename: Ju Hong
authors.initials: JH
authors.lastname: Jeon
authors.forename: Chai Wan
authors.initials: CW
authors.lastname: Kim
authors.forename: Dong Myung
authors.initials: DM
authors.lastname: Shin
authors.forename: Kyu il
authors.initials: Ki
authors.lastname: Kim
authors.forename: Sung Yup
authors.initials: SY
authors.lastname: Cho
authors.forename: Joon Cheol
authors.initials: JC
authors.lastname: Kwon
authors.forename: Kyung Ho
authors.initials: KH
authors.lastname: Choi
authors.forename: Heun Soo
authors.initials: HS
authors.lastname: Kang
authors.forename: In Gyu
authors.initials: IG
authors.lastname: Kim
mesh_terms: D000588:Amines / Q000737:chemistry / Q000378:metabolism; D001710:Biotin / Q000737:chemistry / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D011073:Polyamines / Q000737:chemistry / Q000378:metabolism*; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D015203:Reproducibility of Results; D013096:Spermine / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D011503:Transglutaminases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000588:Amines; D011073:Polyamines; D013096:Spermine; D001710:Biotin; C005264:n-amylamine; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins; D002118:Calcium