PMID- 10572014
OWN - NLM
STAT- MEDLINE
DCOM- 19991217
LR  - 20190613
IS  - 0006-2960 (Print)
IS  - 0006-2960 (Linking)
VI  - 38
IP  - 43
DP  - 1999 Oct 26
TI  - Multiple in vivo tyrosine phosphorylation sites in EphB receptors.
PG  - 14396-408
AB  - Autophosphorylation regulates the function of receptor tyrosine kinases. To
      dissect the mechanism by which Eph receptors transmit signals, we have developed 
      an approach using matrix-assisted laser desorption-ionization (MALDI) mass
      spectrometry to map systematically their in vivo tyrosine phosphorylation sites. 
      With this approach, phosphorylated peptides from receptors digested with various 
      endoproteinases were selectively isolated on immobilized anti-phosphotyrosine
      antibodies and analyzed directly by MALDI mass spectrometry. Multiple in vivo
      tyrosine phosphorylation sites were identified in the juxtamembrane region,
      kinase domain, and carboxy-terminal tail of EphB2 and EphB5, and found to be
      remarkably conserved between these EphB receptors. A number of these sites were
      also identified as in vitro autophosphorylation sites of EphB5 by phosphopeptide 
      mapping using two-dimensional chromatography. Only two in vitro tyrosine
      phosphorylation sites had previously been directly identified for Eph receptors. 
      Our data further indicate that in vivo EphB2 and EphB5 are also extensively
      phosphorylated on serine and threonine residues. Because phosphorylation at each 
      site can affect receptor signaling properties, the multiple phosphorylation sites
      identified here for the EphB receptors suggest a complex regulation of their
      functions, presumably achieved by autophosphorylation as well as phosphorylation 
      by other kinases. In addition, we show that MALDI mass spectrometry can be used
      to determine the binding sites for Src homology 2 (SH2) domains by identifying
      the EphB2 phosphopeptides that bind to the SH2 domain of the Src kinase.
FAU - Kalo, M S
AU  - Kalo MS
AD  - The Burnham Institute, La Jolla, California 92037, USA.
FAU - Pasquale, E B
AU  - Pasquale EB
LA  - eng
GR  - CA73195/CA/NCI NIH HHS/United States
GR  - HD25938/HD/NICHD NIH HHS/United States
GR  - HD26351/HD/NICHD NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Biochemistry
JT  - Biochemistry
JID - 0370623
RN  - 0 (Recombinant Proteins)
RN  - 42HK56048U (Tyrosine)
RN  - EC 2.7.10.1 (Receptor Protein-Tyrosine Kinases)
RN  - EC 2.7.10.1 (Receptor, EphB2)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Binding Sites
MH  - Cells, Cultured
MH  - Chick Embryo
MH  - Humans
MH  - Kidney/cytology/metabolism
MH  - Molecular Sequence Data
MH  - Mutagenesis, Site-Directed
MH  - Peptide Mapping
MH  - Phosphorylation
MH  - Receptor Protein-Tyrosine Kinases/chemistry/genetics/*metabolism
MH  - Receptor, EphB2
MH  - Recombinant Proteins/chemistry/genetics/metabolism
MH  - Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
MH  - Tyrosine/chemistry/*metabolism
MH  - src Homology Domains
EDAT- 1999/11/26 00:00
MHDA- 1999/11/26 00:01
CRDT- 1999/11/26 00:00
PHST- 1999/11/26 00:00 [pubmed]
PHST- 1999/11/26 00:01 [medline]
PHST- 1999/11/26 00:00 [entrez]
AID - bi991628t [pii]
AID - 10.1021/bi991628t [doi]
PST - ppublish
SO  - Biochemistry. 1999 Oct 26;38(43):14396-408. doi: 10.1021/bi991628t.