PMID- 1544940
OWN - NLM
STAT- MEDLINE
DCOM- 19920414
LR  - 20210210
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 267
IP  - 8
DP  - 1992 Mar 15
TI  - Retention of the transforming growth factor-beta 1 precursor in the Golgi complex 
      in a latent endoglycosidase H-sensitive form.
PG  - 5668-75
AB  - Transforming growth factor-beta 1 (TGF-beta 1) is synthesized as a latent high 
      molecular weight complex in a human erythroleukemia cell line, HEL, treated with 
      phorbol 12-myristate 13-acetate. The complex is comprised of three components: 
      mature TGF-beta 1, the TGF-beta 1 latency-associated peptide (beta 1-LAP), and 
      the latent TGF-beta 1-binding protein (LTBP). LTBP plays an important role in the 
      assembly and secretion of the latent TGF-beta 1 complex; if the TGF-beta 1 
      precursor fails to bind to LTBP, much of it remains inside the cells and may 
      contain anomalous disulfide bond(s) between beta 1-LAP and the mature TGF-beta 1 
      molecule (Miyazono, K., Olofsson, A., Colosetti, P., and Heldin, C.-H. (1991) 
      EMBO J. 10, 1091-1101). In the present work, we have investigated the subcellular 
      localization and properties of the TGF-beta 1 precursor retained intracellularly. 
      When the HEL cells were metabolically labeled and chased for up to 72 h, a 
      considerable part of the TGF-beta 1 precursor was still observed intracellularly 
      in an unprocessed form. The secreted form of the TGF-beta 1 precursor was 
      resistant to endoglycosidase H, whereas the intracellular form of the TGF-beta 1 
      precursor was sensitive to endoglycosidase H, regardless of the presence or 
      absence of swainsonine, an inhibitor of mannosidase II. Indirect 
      immunofluorescence microscopy revealed that the TGF-beta 1 precursor co-localized 
      with mannosidase II, a marker for the Golgi complex, but not with protein 
      disulfide isomerase, a marker for the endoplasmic reticulum. The intracellular 
      TGF-beta 1 precursor was prepared from phorbol 12-myristate 13-acetate-treated 
      HEL cells and tested for TGF-beta 1 bioactivity. Half-maximal inhibition of the 
      DNA synthesis in mink lung epithelial cells, Mv1Lu, was observed at 80 pM of the 
      acid-treated TGF-beta 1 precursor, whereas nontreated material showed minimal 
      growth inhibitory activity. Taken together, these results indicate that the 
      TGF-beta 1 precursor is retained inside the cells in the Golgi complex, mainly in 
      a latent, immature form.
FAU - Miyazono, K
AU  - Miyazono K
AD  - Ludwig Institute for Cancer Research, Biomedical Center, Uppsala, Sweden.
FAU - Thyberg, J
AU  - Thyberg J
FAU - Heldin, C H
AU  - Heldin CH
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 (Protein Precursors)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Transforming Growth Factor beta)
RN  - EC 3.2.1.96 (Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase)
RN  - NI40JAQ945 (Tetradecanoylphorbol Acetate)
SB  - IM
MH  - Animals
MH  - Cell Line
MH  - DNA Replication/drug effects
MH  - Fluorescent Antibody Technique
MH  - Golgi Apparatus/drug effects/*metabolism/ultrastructure
MH  - Humans
MH  - Leukemia, Erythroblastic, Acute
MH  - Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase/*metabolism
MH  - Models, Biological
MH  - Protein Precursors/biosynthesis/*metabolism
MH  - Recombinant Proteins/pharmacology
MH  - Tetradecanoylphorbol Acetate/pharmacology
MH  - Transforming Growth Factor beta/biosynthesis/genetics/*metabolism/pharmacology
EDAT- 1992/03/15 00:00
MHDA- 1992/03/15 00:01
CRDT- 1992/03/15 00:00
PHST- 1992/03/15 00:00 [pubmed]
PHST- 1992/03/15 00:01 [medline]
PHST- 1992/03/15 00:00 [entrez]
AID - S0021-9258(18)42818-9 [pii]
PST - ppublish
SO  - J Biol Chem. 1992 Mar 15;267(8):5668-75.