PDBsum entry: 1f0m

Signaling protein

PDB id: 1f0m

Contents

Protein chain

71 a.a. *

Waters ×113

* Residue conservation analysis

PDB id:

1f0m

Name:

Signaling protein

Title:

Monomeric structure of the human ephb2 sam (sterile alpha motif) domain

Structure:

Ephrin type-b receptor 2. Chain: a. Fragment: ephb2 receptor fragment, sam domain. Synonym: ephb2

Source:

Homo sapiens. Human. Organism_taxid: 9606

Resolution:

2.20Å R-factor: 0.243 R-free: 0.264

Authors:

C.D.Thanos,S.Faham,K.E.Goodwill,D.Cascio,M.Phillips, J.U.Bowie

Key ref:

C.D.Thanos et al. (1999). Monomeric structure of the human EphB2 sterile alpha motif domain. J Biol Chem, 274, 37301-37306. PubMed id: 10601296 DOI: 10.1074/jbc.274.52.37301

Date:

16-May-00 Release date: 04-Jul-00

Protein chain

P29323  (EPHB2_HUMAN) -  Ephrin type-B receptor 2

Seq: 1055 a.a.

Struc: 71 a.a.

Enzyme reactions

• Enzyme class: E.C.2.7.10.1 - Receptor protein-tyrosine kinase.
• Reaction: ATP + a [protein]-L-tyrosine = ADP + a [protein]-L-tyrosine phosphate

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

 Gene Ontology (GO) functional annotation 

• Biochemical function: protein binding (1 term)

reference

DOI no: 10.1074/jbc.274.52.37301

J Biol Chem 274:37301-37306 (1999)

PubMed id: 10601296

Monomeric structure of the human EphB2 sterile alpha motif domain.

C.D.Thanos, S.Faham, K.E.Goodwill, D.Cascio, M.Phillips, J.U.Bowie.

ABSTRACT

The sterile alpha motif (SAM) domain is a protein module found in many diverse signaling proteins. SAM domains in some systems have been shown to self-associate. Previous crystal structures of an EphA4-SAM domain dimer (Stapleton, D., Balan, I., Pawson, T., and Sicheri, F. (1999) Nat. Struct. Biol. 6, 44-49) and a possible EphB2-SAM oligomer (Thanos, C. D., Goodwill, K. E., and Bowie, J. U. (1999) Science 283, 833-836) both revealed large interfaces comprising an exchange of N-terminal peptide arms. Within the arm, a conserved hydrophobic residue (Tyr-8 in the EphB2-SAM structure or Phe-910 in the EphA4-SAM structure) is anchored into a hydrophobic cleft on a neighboring molecule. Here we have solved a new crystal form of the human EphB2-SAM domain that has the same overall SAM domain fold yet has no substantial intermolecular contacts. In the new structure, the N-terminal peptide arm of the EphB2-SAM domain protrudes out from the core of the molecule, leaving both the arm (including Tyr-8) and the hydrophobic cleft solvent-exposed. To verify that Tyr-8 is solvent-exposed in solution, we made a Tyr-8 to Ala-8 mutation and found that the EphB2-SAM domain structure and stability were only slightly altered. These results suggest that Tyr-8 is not part of the hydrophobic core of the EphB2-SAM domain and is conserved for functional reasons. Cystallographic evidence suggests a possible role for the N-terminal arm in oligomerization. In the absence of a direct demonstration of biological relevance, however, the functional role of the N-terminal arm remains an open question.

Selected figure(s)

Figure 3.
Fig. 3. Stereo diagram of superimposed SAM structures. The C coordinates of the previously solved Ets-1-SAM (yellow) and oEphB2-SAM (blue) structures was aligned with the C coordinates of residues 14-75 of the mEphB2-SAM (red) structure presented here. The program ALIGN was used to overlap the structures. Tyr-8 of EphB2-SAM and Trp44 of Ets-1-SAM are shown in ball-and-stick representations.

Figure 6.
Fig. 6. Thermal denaturation of EphB2-SAM and EphB2-SAM-Y8A. EphB2-SAM is shown in circles, and EphB2-SAM-Y8A is shown in squares.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (1999, 274, 37301-37306) copyright 1999.

Figures were selected by the author.