PMID- 3882697
OWN - NLM
STAT- MEDLINE
DCOM- 19850404
LR  - 20210210
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 260
IP  - 4
DP  - 1985 Feb 25
TI  - Biosynthesis of rat insulin-like growth factor II. I. Immunochemical 
      demonstration of a approximately 20-kilodalton biosynthetic precursor of rat 
      insulin-like growth factor II in metabolically labeled BRL-3A rat liver cells.
PG  - 2570-7
AB  - BRL-3A rat liver cells synthesize mature 7484-dalton rat insulin-like growth 
      factor II (rIGF-II) as a approximately 22-kDa precursor, presumably 
      prepro-rIGF-II. In the present study, we have biosynthetically labeled intact 
      BRL-3A cells with [35S]cysteine and immunoprecipitated cell lysates and media 
      with antisera to rIGF-II. A approximately 20-kDa protein was identified in 
      immunoprecipitates of cell lysates having properties consistent with pro-rIGF-II. 
      The approximately 20-kDa protein is precipitated by immune sera but not by 
      nonimmune serum. Its immunoprecipitation is specifically inhibited by unlabeled 
      rIGF-II but not by insulin. It is not precipitated from labeled lysates of a 
      subclone of BRL-3A cells (BRL-3A2) that does not synthesize rIGF-II. The 
      approximately 20-kDa protein is rapidly labeled intracellularly (10 min) but is 
      not detected in BRL-3A media. In pulse-chase experiments, radioactivity in the 
      approximately 20-kDa protein disappears during the chase and appears, at later 
      times, in specifically immunoprecipitated approximately 19-, approximately 10-, 
      approximately 8-, and approximately 7-kDa proteins in media and, to a limited 
      extent, intracellularly. A protein with electrophoretic mobility identical to 
      that of the approximately 20-kDa protein observed in cell lysates is 
      immunoprecipitated from 35S-proteins whose synthesis is directed by BRL-3A RNA in 
      a reticulocyte lysate cell-free translation system supplemented with microsomal 
      membranes, and presumably arises by cotranslational removal of the signal peptide 
      from approximately 22-kDa prepro-rIGF-II. Processing of the approximately 20-kDa 
      protein in intact BRL-3A cells to intermediate and mature rIGF-II species appears 
      to occur at the time of secretion and/or shortly thereafter, with the different 
      forms appearing at approximately the same time.
FAU - Yang, Y W
AU  - Yang YW
FAU - Romanus, J A
AU  - Romanus JA
FAU - Liu, T Y
AU  - Liu TY
FAU - Nissley, S P
AU  - Nissley SP
FAU - Rechler, M M
AU  - Rechler MM
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Insulin)
RN  - 0 (Protease Inhibitors)
RN  - 0 (Protein Precursors)
RN  - 0 (Somatomedins)
RN  - K848JZ4886 (Cysteine)
SB  - IM
MH  - Animals
MH  - Cell Line
MH  - Cysteine/metabolism
MH  - Immunosorbent Techniques
MH  - Insulin/*biosynthesis
MH  - Kinetics
MH  - Liver/*metabolism
MH  - Molecular Weight
MH  - *Peptide Biosynthesis
MH  - Protease Inhibitors/pharmacology
MH  - Protein Biosynthesis
MH  - Protein Precursors/*biosynthesis
MH  - Protein Processing, Post-Translational
MH  - Rats
MH  - Somatomedins/*biosynthesis
EDAT- 1985/02/25 00:00
MHDA- 1985/02/25 00:01
CRDT- 1985/02/25 00:00
PHST- 1985/02/25 00:00 [pubmed]
PHST- 1985/02/25 00:01 [medline]
PHST- 1985/02/25 00:00 [entrez]
AID - S0021-9258(18)89590-4 [pii]
PST - ppublish
SO  - J Biol Chem. 1985 Feb 25;260(4):2570-7.