PMID- 2553692
OWN - NLM
STAT- MEDLINE
DCOM- 19891127
LR  - 20210320
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 264
IP  - 30
DP  - 1989 Oct 25
TI  - Generation of Lys-gamma 3-melanotropin from pro-opiomelanocortin 1-77 by a bovine 
      intermediate lobe secretory vesicle membrane-associated aspartic protease and 
      purified pro-opiomelanocortin converting enzyme.
PG  - 17796-801
AB  - The ability of bovine intermediate lobe secretory vesicle membrane-associated 
      enzyme(s) and purified, soluble paired basic residue-specific, 
      pro-opiomelanocortin converting enzyme (Loh, Y.P., Parish, D. C., and Tuteja, R. 
      (1985) J. Biol. Chem. 260, 7194-7205) to cleave bovine NH2-terminal 
      pro-opiomelanocortin1-77 (N-POMC 1-77) was investigated. Purified 
      pro-opiomelanocortin converting enzyme and an enzyme activity associated with the 
      secretory vesicle membrane were shown to cleave bovine N-POMC1-77 to two major 
      products: N-POMC1-49 and Lys-gamma 3-melanotropin (MSH), and one minor product, 
      gamma 3-MSH. These products were identified by their retention times on high 
      performance liquid chromatography, immunological characteristics, and for 
      Lys-gamma 3-MSH, amino acid composition. The products generated indicate cleavage 
      preferentially between Arg 49-Lys 50 of bN-POMC1-77 (where b indicates bovine), 
      which is identical to the processing pattern found in the bovine intermediate 
      lobe in situ. The membrane converting activity was shown to be stimulated by 5 mM 
      Ca2+ and has a pH optimum of 4-5 and an inhibitor profile characteristic of an 
      aspartic protease. This suggests that the membrane-associated enzyme involved is 
      very similar or identical to the purified, soluble pro-opiomelanocortin 
      converting enzyme, which has previously been reported to be an acidic, aspartic 
      protease responsible for the initial steps of POMC processing. The results of 
      this study lead to the proposal that the lack of processing of the Arg49-Lys50 
      site in POMC in the anterior lobe versus the intermediate lobe of the pituitary 
      in vivo may be due to other regulatory mechanisms rather than invoking the 
      existence in the intermediate lobe of another enzyme specific for this site, 
      different from pro-opiomelanocortin converting enzyme.
FAU - Estivariz, F E
AU  - Estivariz FE
AD  - Section on Cellular Neurobiology, National Institute of Child Health and Human 
      Development, Bethesda, Maryland 20892.
FAU - Birch, N P
AU  - Birch NP
FAU - Loh, Y P
AU  - Loh YP
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Peptide Fragments)
RN  - 0 (Protease Inhibitors)
RN  - 66796-54-1 (Pro-Opiomelanocortin)
RN  - 83310-33-2 (MSH, Lys-gamma(3))
RN  - EC 3.4.- (Endopeptidases)
RN  - EC 3.4.21.- (Proprotein Convertases)
RN  - EC 3.4.23.- (Aspartic Acid Endopeptidases)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Aspartic Acid Endopeptidases
MH  - Cattle
MH  - Cytoplasmic Granules/*enzymology
MH  - Endopeptidases/isolation & purification/*metabolism
MH  - Hydrogen-Ion Concentration
MH  - Intracellular Membranes/*enzymology
MH  - Kinetics
MH  - Molecular Sequence Data
MH  - Peptide Fragments/*genetics
MH  - Pituitary Gland/*enzymology
MH  - Pro-Opiomelanocortin/*genetics/metabolism
MH  - Proprotein Convertases
MH  - Protease Inhibitors/pharmacology
MH  - *Protein Processing, Post-Translational
EDAT- 1989/10/25 00:00
MHDA- 1989/10/25 00:01
CRDT- 1989/10/25 00:00
PHST- 1989/10/25 00:00 [pubmed]
PHST- 1989/10/25 00:01 [medline]
PHST- 1989/10/25 00:00 [entrez]
AID - S0021-9258(19)84643-4 [pii]
PST - ppublish
SO  - J Biol Chem. 1989 Oct 25;264(30):17796-801.