PMID- 10419520
OWN - NLM
STAT- MEDLINE
DCOM- 19990819
LR  - 20200111
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 31
DP  - 1999 Jul 30
TI  - Membrane topology of S2P, a protein required for intramembranous cleavage of
      sterol regulatory element-binding proteins.
PG  - 21973-80
AB  - In sterol-depleted mammalian cells, a two-step proteolytic process releases the
      NH(2)-terminal domains of sterol regulatory element-binding proteins (SREBPs)
      from membranes of the endoplasmic reticulum (ER). These domains translocate into 
      the nucleus, where they activate genes of cholesterol and fatty acid
      biosynthesis. The SREBPs are oriented in the membrane in a hairpin fashion, with 
      the NH(2)- and COOH-terminal domains facing the cytosol and a single hydrophilic 
      loop projecting into the lumen. The first cleavage occurs at Site-1 within the ER
      lumen to generate an intermediate that is subsequently released from the membrane
      by cleavage at Site-2, which lies within the first transmembrane domain. A
      membrane protein, designated S2P, a putative zinc metalloprotease, is required
      for this cleavage. Here, we use protease protection and glycosylation site
      mapping to define the topology of S2P in ER membranes. Both the NH(2) and COOH
      termini of S2P face the cytosol. Most of S2P is hydrophobic and appears to be
      buried in the membrane. All three of the long hydrophilic sequences of S2P can be
      glycosylated, indicating that they all project into the lumen. The HEIGH sequence
      of S2P, which contains two potential zinc-coordinating residues, is contained
      within a long hydrophobic segment. Aspartic acid 467, located approximately 300
      residues away from the HEIGH sequence, appears to provide the third coordinating 
      residue for the active site zinc. This residue, too, is located in a hydrophobic 
      sequence. The hydrophobicity of these sequences suggests that the active site of 
      S2P is located within the membrane in an ideal position to cleave its target, a
      Leu-Cys bond in the first transmembrane helix of SREBPs.
FAU - Zelenski, N G
AU  - Zelenski NG
AD  - Department of Molecular Genetics, University of Texas Southwestern Medical
      Center, Dallas, Texas 75235, USA.
FAU - Rawson, R B
AU  - Rawson RB
FAU - Brown, M S
AU  - Brown MS
FAU - Goldstein, J L
AU  - Goldstein JL
LA  - eng
GR  - HL20948/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
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 (CCAAT-Enhancer-Binding Proteins)
RN  - 0 (DNA-Binding Proteins)
RN  - 0 (Membrane Proteins)
RN  - 0 (Nuclear Proteins)
RN  - 0 (Recombinant Fusion Proteins)
RN  - 0 (SREBF1 protein, human)
RN  - 0 (Sterol Regulatory Element Binding Protein 1)
RN  - 0 (Transcription Factors)
RN  - EC 3.4.24.- (Metalloendopeptidases)
RN  - EC 3.4.24.85 (MBTPS2 protein, human)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - *CCAAT-Enhancer-Binding Proteins
MH  - CHO Cells
MH  - Cell Line
MH  - Cell Membrane/metabolism/ultrastructure
MH  - Cricetinae
MH  - DNA-Binding Proteins/chemistry/genetics/*metabolism
MH  - Glycosylation
MH  - Humans
MH  - Kidney
MH  - Membrane Proteins/*chemistry/genetics/*metabolism
MH  - Metalloendopeptidases/*chemistry/*metabolism
MH  - Molecular Sequence Data
MH  - Mutagenesis, Insertional
MH  - Nuclear Proteins/chemistry/genetics/*metabolism
MH  - Protein Conformation
MH  - Recombinant Fusion Proteins/biosynthesis
MH  - Sterol Regulatory Element Binding Protein 1
MH  - Transcription Factors/metabolism
MH  - Transfection
EDAT- 1999/07/27 00:00
MHDA- 1999/07/27 00:01
CRDT- 1999/07/27 00:00
PHST- 1999/07/27 00:00 [pubmed]
PHST- 1999/07/27 00:01 [medline]
PHST- 1999/07/27 00:00 [entrez]
AID - 10.1074/jbc.274.31.21973 [doi]
PST - ppublish
SO  - J Biol Chem. 1999 Jul 30;274(31):21973-80. doi: 10.1074/jbc.274.31.21973.