Polyubiquitin in crustacean striated muscle: increased expression and conjugation during molt-induced claw muscle atrophy
| Autor: | Donald L. Mykles, Blair S. Shean |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Untranslated region
animal structures DNA Complementary Proteolysis Immunoblotting Molecular Sequence Data Biophysics Gene Expression Muscle Proteins Molting Biochemistry Biopolymers Ubiquitin Structural Biology Sequence Homology Nucleic Acid Genetics medicine Animals Amino Acid Sequence Polyubiquitin Peptide sequence Ubiquitins Messenger RNA medicine.diagnostic_test biology Base Sequence Molecular biology Muscle atrophy Nephropidae Proteasome biology.protein medicine.symptom Myofibril DNA Probes |
| Zdroj: | Biochimica et biophysica acta. 1264(3) |
| ISSN: | 0006-3002 |
| Popis: | The claw muscles of decapod crustaceans undergo a molt-induced atrophy to facilitate withdrawal of the claws at ecdysis. Polyubiquitin expression, as well as the levels of ubiquitin conjugates, a ubiquitin-conjugating enzyme involved in the ATP/ubiquitin-dependent proteolytic pathway (crustacean E2 16 kDa homolog of Drosophila UbcDl), and proteasome, were examined to determine the role of ATP/ubiquitin-dependent proteolysis in the enhanced degradation of myofibrillar proteins during muscle atrophy. A partial-length clone (1.7 kb) of polyubiquitin was isolated from a lobster muscle cDNA library; the 5′ end lacked the 5′ untranslated region (UTR) and the beginning of the first ubiquitin monomer, while the 3′ end contained the terminal ubiquitin monomer and 3′ UTR. The deduced amino acid sequence was 100% identical with that from Manduca, Drosophila , and human. In land crab claw muscle, the polyubiquitin mRNA (2.7 kb) increased about 5-fold and ubiquitin-protein conjugates (> 200 kDa) increased about 8-fold during atrophy. In contrast, the level of a ubiquitin-conjugating enzyme (E2 16 kDa ) remained unchanged. The proteasome, which constitutes the catalytic core of the ATP/ubiquitin-dependent proteinase complex, increased about 2-fold during proecdysis, reaching its highest level immediately before ecdysis. These results suggest that the ATP/ubiquitin-dependent proteolytic pathway contributes to the changes in protein metabolism that occur during molt-induced muscle atrophy. |
| Databáze: | OpenAIRE |
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