Hepatic ligandin subunits and mRNAs during development.
Eight-week-old rats had twofold higher hepatic ligandin concentration than 10-day-old animals as determined immunologically and by steroid isomerase and glutathione S-transferase assays. Increased ligandin content was accompanied by parallel increase in subunit synthesis as determined by [3H]leucine incorporation into each subunit relative to incorporation into total cytosolic proteins. The mRNA content for each ligandin subunit was twofold higher in older animals as determined by cell-free in vitro translation followed by immunoprecipitation and dot hybridization using a ligandin cDNA probe. When poly A mRNA from the postmitochondrial fraction of liver from young or old rats was subjected to agarose gel electrophoresis under denaturing conditions and hybridized to ligandin cDNA probe, a single 11 S band was obtained. With RNA from total liver, an additional 13 S band was obtained, suggesting the existence of a precursor form of ligandin mRNA. Since precursor polypeptides were not observed with RNA from total liver in cell-free in vitro translation systems, the precursor form requires processing to the 11 S form before the mRNA becomes functional.
D000375:Aging; D000818:Animals; D004247:DNA / Q000378:metabolism; D005982:Glutathione Transferase / Q000235:genetics*; D008099:Liver / Q000201:enzymology / Q000254:growth & development*; D046911:Macromolecular Substances; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics*; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D012156:Reticulocytes / Q000378:metabolism
D046911:Macromolecular Substances; D012333:RNA, Messenger; D004247:DNA; D005982:Glutathione Transferase