PDBsum entry 2f3n

Structural protein

PDB id: 2f3n

Contents

Protein chains

65 a.a. *

Waters ×162

* Residue conservation analysis

PDB id:

2f3n

Name:

Structural protein

Title:

Crystal structure of the native shank sam domain.

Structure:

Sh3 and multiple ankyrin repeat domains 3. Chain: a, b, c. Fragment: sam domain. Synonym: shank3, proline-rich synapse associated protein 2, prosap2, spank-2. Engineered: yes. Mutation: yes

Source:

Rattus norvegicus. Norway rat. Organism_taxid: 10116. Gene: shank3. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.

Resolution:

2.10Å R-factor: 0.206 R-free: 0.251

Authors:

M.K.Baron,J.U.Bowie,S.Faham

Key ref:

M.K.Baron et al. (2006). An architectural framework that may lie at the core of the postsynaptic density. Science, 311, 531-535. PubMed id: 16439662 DOI: 10.1126/science.1118995

Date:

22-Nov-05 Release date: 07-Feb-06

Protein chains

Q9JLU4  (SHAN3_RAT) -  SH3 and multiple ankyrin repeat domains protein 3 from Rattus norvegicus

Seq: 1740 a.a.

Struc: 65 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

DOI no: 10.1126/science.1118995

Science 311:531-535 (2006)

PubMed id: 16439662

An architectural framework that may lie at the core of the postsynaptic density.

M.K.Baron, T.M.Boeckers, B.Vaida, S.Faham, M.Gingery, M.R.Sawaya, D.Salyer, E.D.Gundelfinger, J.U.Bowie.

ABSTRACT

The postsynaptic density (PSD) is a complex assembly of proteins associated with the postsynaptic membrane that organizes neurotransmitter receptors, signaling pathways, and regulatory elements within a cytoskeletal matrix. Here we show that the sterile alpha motif domain of rat Shank3/ProSAP2, a master scaffolding protein located deep within the PSD, can form large sheets composed of helical fibers stacked side by side. Zn2+, which is found in high concentrations in the PSD, binds tightly to Shank3 and may regulate assembly. Sheets of the Shank protein could form a platform for the construction of the PSD complex.

Selected figure(s)

Figure 1.
Fig. 1. The Shank3 SAM domain forms large sheets of helical fibers. (A) An EM image of Shank-SAM reveals over 25 fibers stacked side by side in a two-dimensional sheet. (B) At higher magnification, the well-ordered nature of the sheet can be seen as individual subunits that are arranged in a highly ordered array. (C) The packing of Shank-SAM into a sheet is also evident in the crystal structure of Shank-SAM M56E (a soluble mutant) solved to 2.1 Å. Yellow and blue depict fibers stacked in opposite orientations. Both the antiparallel and parallel orientations are seen in the crystal, but we believe the antiparallel orientation is physiologically relevant for several reasons. First, the interfiber interface buries more surface area in the antiparallel orientation (1264 Å2 versus 852 Å2). Second, the position of a mutation that solubilizes the protein (W5E) is in the interface between antiparallel fibers (Fig. 2C) but not parallel fibers. Finally, Zn2+, which has a dramatic effect on sheet organization, stabilizes salt bridges between antiparallel fibers but not parallel fibers (Fig. 3C). In the numbering scheme used for the crystal structure, residue 1 corresponds to residue 174 in the full rat Shank3 sequence.

Figure 4.
Fig. 4. Assembly mutants prevent the localization of Shank to the synapse. Visualization of Shank variant distributions in transfected hippocampal neurons is shown. The wild-type Shank-416-GFP construct (green) clusters in neuronal dendrites and colocalizes with Bassoon (red) in transfected hippocampal neurons (insets: left, GFP; middle, Bassoon; right, merge). In contrast, mutants (W5E, H22A, M56E, and all three double mutants) display a diffusely distributed green fluorescence, indicating no preferential localization to synaptic sites as indicated by Bassoon staining (insets). F8E shows partial clustering and partial colocalization with Bassoon (inset).

The above figures are reprinted by permission from the AAAs: Science (2006, 311, 531-535) copyright 2006.

Figures were selected by the author.