Thyroid hormone-dependent expression of bullfrog tadpole collagenase gene.

摘要: Collagenase has been suggested to play a pivotal role in tissue remodeling during anuran metamorphosis. RNA blot analysis and nuclear run-on assay showed that collagenase genes of caudal cells tadpoles the bullfrog, Rana catesbeiana, are up-regulated by thyroid hormone after only 24 h. The gene for was cloned from genome DNA bullfrog its structure, including 5'-upstream region with-1 kbp, determined. contained 4 exons with sequences enzyme active centre exon 2. Cis-acting regulatory were recognized as AP-1 Sp1, which had also found mammalian gene. A special sequence noticed near -870 bp, 5'-AG-GTAAGAACAGGATA-3', satisfies general criterion identification responsive element (TRE) proposed Umesono et al. (1991) is homologous reported thyroid-hormone proteins such receptor (TR) β, growth hormone, malic myosin heavy chain. Results gel mobility shift supported idea functions TRE. supershift procedure demonstrated complex formed contains TR. present study revealed uniqueness metamorphosis-associated enzyme, because, our knowledge, known do not contain THE their transcription regions.