| First Author | Johnson KB | Year | 2012 |
| Journal | Am J Physiol Heart Circ Physiol | Volume | 302 |
| Issue | 7 | Pages | H1355-66 |
| PubMed ID | 22307675 | Mgi Jnum | J:315477 |
| Mgi Id | MGI:6829032 | Doi | 10.1152/ajpheart.00918.2011 |
| Citation | Johnson KB, et al. (2012) Vena cava and aortic smooth muscle cells express transglutaminases 1 and 4 in addition to transglutaminase 2. Am J Physiol Heart Circ Physiol 302(7):H1355-66 |
| abstractText | Transglutaminase (TG) function facilitates several vascular processes and diseases. Although many of these TG-dependent vascular processes have been ascribed to the function of TG2, TG2 knockout mice have a mild vascular phenotype. We hypothesized that TGs besides TG2 exist and function in the vasculature. Biotin-pentylamide incorporation, a measure of general TG activity, was similar in wild-type and TG2 knockout mouse aortae, and the general TG inhibitor cystamine reduced biotin-pentylamine incorporation to a greater extent than the TG2-specific inhibitor Z-DON, indicating the presence of other functional TGs. Additionally, 5-hydroxytryptamine-induced aortic contraction, a TG-activity-dependent process, was decreased to a greater extent by general TG inhibitors vs. Z-DON (maximum contraction: cystamine = abolished, monodansylcadaverine = 28.6 +/- 14.9%, and Z-DON = 60.2 +/- 15.2% vehicle), providing evidence for the importance of TG2-independent activity in the vasculature. TG1, TG2, TG4, and Factor XIII (FXIII) mRNA in rat aortae and vena cavae was detected by RT-PCR. Western analysis detected TG1 and TG4, but not FXIII, in rat aortae and vena cavae and in TG2 knockout and wild-type mouse aortae. Immunostaining confirmed the presence of TG1, TG2, and TG4 in rat aortae and vena cavae, notably in smooth muscle cells; FXIII was absent. K5 and T26, FITC-labeled peptide substrates specific for active TG1 and TG2, respectively, were incorporated into rat aortae and vena cavae and wild-type, but not TG2 knockout, mouse aortae. These studies demonstrate that TG2-independent TG activity exists in the vasculature and that TG1 and TG4 are expressed in vascular tissues. |
