Portal de Periódicos da CAPES

Sunday: Poster Sessions, Pt.I

1993; American Society for Cell Biology; Volume: 4; Issue: suppl Linguagem: Inglês

10.1091/mbc.4.suppl.7a

1939-4586

Metaloproteases such aa matrix metalloprotems (MMPa) and Astacin metalloproteaes (AMPs) have been propored to have an important role during embryonic development.MMPs are implicated in morphogene via their affecta on extracellular matrix (ECM) breakdown while AMPs such as Droophila tdW gene and human BMPI have bee functionally tied to axle specification and cell differentiation via the activation of ECM- associated growth factor such as TGF-L We have utilized the Cnidarian Hydra as a devoopm ental dal for ceIl/ECM intactions to invesigte the role of metllopro in Using gdatin-zymogrphy, five gelatina were ldentd in Hydra vulrris ranging in size from 67kDa to 29kDa.All were matalloprotases.The 29kDa hydra metalloproteae (HMP) was purified, microsequenced, and found to have structurl homobly with human BMPI, Drosophila WB&id, Xenopua UVS.2,ea urchin BP10, and other members of the Astacin family of metalloprotease which have all been tied to axis and/or cell Bad on the data, degenrate PCR primer were developed and used with a hydra cDNA library.Sequence analysi of PCR subclones confirmed that all clones contained the Astacin signature in the Zinc binding domain and Northen blot analysis indicated the presence of two RNA htanipts in the lkb size range.cDNA clone are now being identifled for complete sequence analysis.Antibodies raised to the 29 kDa HMP and to a synthetic peptide of the catalytic domain have a lcalization pettern which is resticted to the ECM of the heed gion of hydra.Anti-29kDa IgG inhibits 29kDa activity as monitored by zymography nd 14C-gSeatin assays and these antibodies also revribly block heed regeeration in hydra.Substrate analysis studies indicate that the 29kDa HMP can degrde human fibronectin but has no effect on BSA or casein.Studie am now underway to determine if the 29kD1 HMP has any function in ECM- associated growth factor activation as has been proposed for other membes of the Astacin family ofmetalro .These studies indicate that 1) Astacn metalloprote_s developed early during metazoan evolution and 2) the 29kDa HMP is axis specific and appears to function in hydra head morphog s via mehanismainvohvW the ECM.