PMID- 10446129
OWN - NLM
STAT- MEDLINE
DCOM- 19990909
LR  - 20210209
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 34
DP  - 1999 Aug 20
TI  - The prostacyclin receptor is isoprenylated. Isoprenylation is required for
      efficient receptor-effector coupling.
PG  - 23707-18
AB  - The prostacyclin receptor (IP), a G protein-coupled receptor, mediates the
      actions of the prostanoid prostacyclin and its mimetics. IPs from a number of
      species each contain identically conserved putative isoprenylation CAAX motifs,
      each with the sequence CSLC. Metabolic labeling of human embryonic kidney (HEK)
      293 cells stably overexpressing the hemagluttinin epitope-tagged IP in the
      presence of [(3)H]mevalonolactone established that the mouse IP is isoprenylated.
      Studies involving in vitro assays confirmed that recombinant forms of the human
      and mouse IP are modified by carbon 15 farnesyl isoprenoids. Disruption of
      isoprenylation, by site-directed mutagenesis of Cys(414) to Ser(414), within the 
      CAAX motif, abolished isoprenylation of IP(SSLC) both in vitro and in transfected
      cells. Scatchard analysis of the wild type (IP) and mutant (IP(SSLC)) receptor
      confirmed that each receptor exhibited high and low affinity binding sites for
      [(3)H]iloprost, which were not influenced by receptor isoprenylation. Whereas
      stable cell lines overexpressing IP generated significant agonist (iloprost and
      cicaprost)-mediated increases in cAMP relative to nontransfected cells, cAMP
      generation by IP(SSLC) cells was not significantly different from the control,
      nontransfected HEK 293 cells. Moreover, co-expression of the alpha (alpha)
      subunit of Gs generated significant augmentations in cAMP by IP but not by
      IP(SSLC) cells. Whereas IP also demonstrated significant, dose-dependent
      increases in [Ca(2+)](i) in response to iloprost or cicaprost compared with the
      nontransfected HEK 293 cells, mobilization of [Ca(2+)](i) by IP(SSLC) was
      significantly impaired. Co-transfection of cells with either Galpha(q) or
      Galpha(11) resulted in significant augmentation of agonist-mediated [Ca(2+)](i)
      mobilization by IP cells but not by IP(SSLC) cells or by the control, HEK 293
      cells. In addition, inhibition of isoprenylation by lovastatin treatment
      significantly reduced agonist-mediated cAMP generation by IP in comparison to the
      nonisoprenylated beta(2) adrenergic receptor or nontreated cells. Hence,
      isoprenylation of IP does not influence ligand binding but is required for
      efficient coupling to the effectors adenylyl cyclase and phospholipase C.
FAU - Hayes, J S
AU  - Hayes JS
AD  - Department of Biochemistry, Merville House, University College Dublin, Belfield, 
      Dublin 4, Ireland.
FAU - Lawler, O A
AU  - Lawler OA
FAU - Walsh, M T
AU  - Walsh MT
FAU - Kinsella, B T
AU  - Kinsella BT
LA  - eng
SI  - GENBANK/Z93039
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 (Polyisoprenyl Phosphates)
RN  - 0 (Receptors, Epoprostenol)
RN  - 0 (Receptors, Prostaglandin)
RN  - 0 (Sesquiterpenes)
RN  - 79W6B01D07 (farnesyl pyrophosphate)
RN  - 9LHU78OQFD (Lovastatin)
RN  - E0399OZS9N (Cyclic AMP)
RN  - EC 3.1.4.- (Type C Phospholipases)
RN  - EC 4.6.1.1 (Adenylyl Cyclases)
RN  - JED5K35YGL (Iloprost)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Adenylyl Cyclases/metabolism
MH  - Animals
MH  - Base Sequence
MH  - Calcium/metabolism
MH  - Cyclic AMP/biosynthesis
MH  - Humans
MH  - Iloprost/metabolism
MH  - Lovastatin/pharmacology
MH  - Mice
MH  - Molecular Sequence Data
MH  - Mutagenesis, Site-Directed
MH  - Polyisoprenyl Phosphates/metabolism
MH  - *Protein Prenylation
MH  - Receptors, Epoprostenol
MH  - Receptors, Prostaglandin/metabolism
MH  - Sesquiterpenes
MH  - Structure-Activity Relationship
MH  - Type C Phospholipases/metabolism
EDAT- 1999/08/14 00:00
MHDA- 1999/08/14 00:01
CRDT- 1999/08/14 00:00
PHST- 1999/08/14 00:00 [pubmed]
PHST- 1999/08/14 00:01 [medline]
PHST- 1999/08/14 00:00 [entrez]
AID - 10.1074/jbc.274.34.23707 [doi]
AID - S0021-9258(19)55482-5 [pii]
PST - ppublish
SO  - J Biol Chem. 1999 Aug 20;274(34):23707-18. doi: 10.1074/jbc.274.34.23707.