PMID- 10518540
OWN - NLM
STAT- MEDLINE
DCOM- 19991124
LR  - 20190501
IS  - 0027-8424 (Print)
IS  - 0027-8424 (Linking)
VI  - 96
IP  - 21
DP  - 1999 Oct 12
TI  - beta2-chimaerin is a novel target for diacylglycerol: binding properties and
      changes in subcellular localization mediated by ligand binding to its C1 domain.
PG  - 11854-9
AB  - The members of the chimaerin family of Rac-GTPase-activating proteins possess a
      single C1 domain with high homology to those present in protein kinase C (PKC)
      isozymes. This domain in PKCs is involved in phorbol ester and diacylglycerol
      (DAG) binding. We previously have demonstrated that one of the chimaerin
      isoforms, beta2-chimaerin, binds phorbol esters with high affinity. In this study
      we analyzed the properties of beta2-chimaerin as a DAG receptor by using a series
      of conformationally constrained cyclic DAG analogues (DAG lactones) as probes. We
      identified analogs that bind to beta2-chimaerin with more than 100-fold higher
      affinity than 1-oleoyl-2-acetylglycerol. The potencies of these analogs approach 
      those of the potent phorbol ester tumor promoters. The different DAG lactones
      show some selectivity for this novel receptor compared with PKCalpha. Cellular
      studies revealed that these DAG analogs induce translocation of beta2-chimaerin
      from cytosolic (soluble) to particulate fractions. Using green fluorescent
      protein-fusion proteins for beta2-chimaerin we determined that this novel
      receptor translocates to the perinuclear region after treatment with DAG
      lactones. Binding and translocation were prevented by mutation of the conserved
      Cys-246 in the C1 domain. The structural homology between the C1 domain of
      beta2-chimaerin and the C1b domain of PKCdelta also was confirmed by modeling
      analysis. Our results demonstrate that beta2-chimaerin is a high affinity
      receptor for DAG through binding to its C1 domain and supports the emerging
      concept that multiple pathways transduce signaling through DAG and the phorbol
      esters.
FAU - Caloca, M J
AU  - Caloca MJ
AD  - Center for Experimental Therapeutics, Department of Pharmacology, University of
      Pennsylvania School of Medicine, Philadelphia, PA 19104-6160, USA.
FAU - Garcia-Bermejo, M L
AU  - Garcia-Bermejo ML
FAU - Blumberg, P M
AU  - Blumberg PM
FAU - Lewin, N E
AU  - Lewin NE
FAU - Kremmer, E
AU  - Kremmer E
FAU - Mischak, H
AU  - Mischak H
FAU - Wang, S
AU  - Wang S
FAU - Nacro, K
AU  - Nacro K
FAU - Bienfait, B
AU  - Bienfait B
FAU - Marquez, V E
AU  - Marquez VE
FAU - Kazanietz, M G
AU  - Kazanietz MG
LA  - eng
GR  - R01 CA074197/CA/NCI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (Diglycerides)
RN  - 0 (Lactones)
RN  - 0 (Ligands)
RN  - 0 (Luminescent Proteins)
RN  - 0 (Neoplasm Proteins)
RN  - 0 (Recombinant Proteins)
RN  - 0 (beta-chimaerin)
RN  - 147336-22-9 (Green Fluorescent Proteins)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Biological Transport
MH  - COS Cells
MH  - Diglycerides/*metabolism
MH  - Green Fluorescent Proteins
MH  - Kinetics
MH  - Lactones/*metabolism
MH  - Ligands
MH  - Luminescent Proteins/metabolism
MH  - Models, Molecular
MH  - Molecular Sequence Data
MH  - Mutagenesis
MH  - Neoplasm Proteins/*metabolism
MH  - Protein Binding
MH  - Recombinant Proteins/metabolism
MH  - Sequence Homology, Amino Acid
MH  - Time Factors
PMC - PMC18376
EDAT- 1999/10/16 00:00
MHDA- 1999/10/16 00:01
CRDT- 1999/10/16 00:00
PHST- 1999/10/16 00:00 [pubmed]
PHST- 1999/10/16 00:01 [medline]
PHST- 1999/10/16 00:00 [entrez]
AID - 10.1073/pnas.96.21.11854 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 1999 Oct 12;96(21):11854-9. doi:
      10.1073/pnas.96.21.11854.