title: Biosynthesis of titin in cultured skeletal muscle cells.
abstract: Although significant progress has been made regarding the structure and function of titin, little data exist on the biosynthesis of this large protein in developing muscle. Using pulse-labeling with [35S]methionine and immunoprecipitation with an anti-titin mAb, we have examined the biosynthesis of titin in synchronized cultures of skeletal muscle cells derived from day 12 chicken embryos. We find that: (a) titin synthesis increases greater than 4-fold during the first week in culture and during this same time period, synthesis of muscle-specific myosin heavy chain increases greater than 12-fold; (b) newly synthesized titin has a t1/2 of approximately 70 h; (c) titin is resistant to extraction with Triton X-100 both during and immediately after its synthesis. These observations suggest that newly synthesized titin molecules are stable proteins that rapidly associate with the cytoskeleton of developing myotubes.
authors.affiliation: Department of Biochemistry, University of Iowa, Iowa City 52242.
authors.forename: W B
authors.initials: WB
authors.lastname: Isaacs
authors.forename: I S
authors.initials: IS
authors.lastname: Kim
authors.forename: A
authors.initials: A
authors.lastname: Struve
authors.forename: A B
authors.initials: AB
authors.lastname: Fulton
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D002645:Chickens; D064211:Connectin; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D015151:Immunoblotting; D007700:Kinetics; D008565:Membrane Proteins / Q000096:biosynthesis*; D008715:Methionine / Q000378:metabolism; D009124:Muscle Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D009132:Muscles / Q000378:metabolism*; D011494:Protein Kinases; D013462:Sulfur Radioisotopes
chemical_list: D000911:Antibodies, Monoclonal; D064211:Connectin; D008565:Membrane Proteins; D009124:Muscle Proteins; D013462:Sulfur Radioisotopes; D008715:Methionine; D011494:Protein Kinases