Publication Date:
1983-10-28
Description:
Extracts of liver from hemizygous affected mice with the X-linked spfash mutation have 5 to 10 percent of normal ornithine transcarbamylase (OTC) activity, yet the homogeneous enzyme isolated from these extracts is identical to that in controls. The OTC messenger RNA from mutant livers programs the synthesis of two distinct OTC precursor polypeptides--one normal in size, the other distinctly elongated. Both precursors are imported and proteolytically processed by mitochondria, but only the normal one is assembled into active trimer. This novel phenotype may result from a mutation in the structural gene for OTC leading, primarily, to aberrant splicing of OTC messenger RNA and, secondarily, to formation of a structurally altered precursor whose posttranslational pathway is ultimately futile because its mature mitochondrial form is not capable of assembly and functional expression.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rosenberg, L E -- Kalousek, F -- Orsulak, M D -- AM 09527/AM/NIADDK NIH HHS/ -- New York, N.Y. -- Science. 1983 Oct 28;222(4622):426-8.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/6623083" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Genes
;
Liver/enzymology
;
Macromolecular Substances
;
Mice
;
Mice, Mutant Strains/genetics/physiology
;
Mitochondria, Liver/enzymology
;
Mutation
;
Ornithine Carbamoyltransferase/*genetics
;
Protein Precursors/genetics
;
Protein Processing, Post-Translational
;
RNA, Messenger/genetics
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
