Interaction of Human Tissue Plasminogen Activator (t-PA) with Pregnancy Zone Protein. A Comparative Study to t-PA- 2-Macroglobulin Interaction

SÁNCHEZ CECILIA,; CHIABRANDO, GUSTAVO A; GUGLIELMONE HUGO,; BONACCI GUSTAVO,; RABINOVICH GABRIEL,; VIDES MIGUEL,

Journal Of Biochemistry Tokio

Oxford Journals

Año: 1998 vol. 124 p. 274 - 274

p class="abstract">Human pregnancy zone protein (PZP) is a major pregnancy-associated plasma protein strongly related to alpha2-macroglobulin (alpha2-M). Interactions of tissue plasminogen activator (t-PA) with PZP and alpha2-M were both investigated in vitro and the complexes were analyzed by polyacrylamide gel electrophoresis (PAGE). The results demonstrated that PZP-t-PA complex formation was evident within 1 h of incubation, whereas alpha2-M-t-PA complexes were formed after 18 h. Conclusions were supported by the following evidence: (i) PZP and alpha2-M complexes revealed changes of the mobility rate in non-denaturing PAGE, similar to those observed with alpha-Ms-chymotrypsin; (ii) both PZP and alpha2-M formed complexes of molecular size >360 kDa by SDS-PAGE, in accordance with the covalent binding of t-PA, which was previously reported for other proteinases; and (iii) PZP underwent a specific cleavage of the bait region with appearence of fragments of 85-90 kDa as judged by re