1 c1griA_
100.0
60
PDB header: signal transduction adaptorChain: A: PDB Molecule: growth factor bound protein 2;
PDBTitle: grb2
2 c2lqnA_
100.0
25
PDB header: signaling proteinChain: A: PDB Molecule: crk-like protein;
PDBTitle: solution structure of crkl
3 c2l3sA_
100.0
26
PDB header: structural proteinChain: A: PDB Molecule: autoinhibited crk protein;
PDBTitle: structure of the autoinhibited crk
4 c2eyzA_
100.0
28
PDB header: signaling proteinChain: A: PDB Molecule: v-crk sarcoma virus ct10 oncogene homolog
PDBTitle: ct10-regulated kinase isoform ii
5 c1ng2A_
100.0
32
PDB header: oxidoreductase activatorChain: A: PDB Molecule: neutrophil cytosolic factor 1;
PDBTitle: structure of autoinhibited p47phox
6 c1ov3A_
100.0
33
PDB header: oxidoreductase activatorChain: A: PDB Molecule: neutrophil cytosol factor 1;
PDBTitle: structure of the p22phox-p47phox complex
7 c1mv3A_
99.9
13
PDB header: endocytosis/exocytosisChain: A: PDB Molecule: myc box dependent interacting protein 1;
PDBTitle: nmr structure of the tumor suppressor bin1: alternative2 splicing in melanoma and interaction with c-myc
8 c2eyyA_
99.9
27
PDB header: signaling proteinChain: A: PDB Molecule: v-crk sarcoma virus ct10 oncogene homolog
PDBTitle: ct10-regulated kinase isoform i
9 d1ng2a2
99.8
24
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
10 c1k9aB_
99.8
34
PDB header: transferaseChain: B: PDB Molecule: carboxyl-terminal src kinase;
PDBTitle: crystal structure analysis of full-length carboxyl-terminal2 src kinase at 2.5 a resolution
11 c1oplA_
99.8
33
PDB header: transferaseChain: A: PDB Molecule: proto-oncogene tyrosine-protein kinase;
PDBTitle: structural basis for the auto-inhibition of c-abl tyrosine2 kinase
12 c2fo0A_
99.8
36
PDB header: transferaseChain: A: PDB Molecule: proto-oncogene tyrosine-protein kinase abl1 (1b isoform);
PDBTitle: organization of the sh3-sh2 unit in active and inactive forms of the2 c-abl tyrosine kinase
13 c2c0iA_
99.8
38
PDB header: transferaseChain: A: PDB Molecule: tyrosine-protein kinase hck;
PDBTitle: src family kinase hck with bound inhibitor a-420983
14 c2dx1A_
99.8
44
PDB header: signaling proteinChain: A: PDB Molecule: rho guanine nucleotide exchange factor 4;
PDBTitle: crystal structure of rhogef protein asef
15 c1x27F_
99.8
38
PDB header: signaling proteinChain: F: PDB Molecule: proto-oncogene tyrosine-protein kinase lck;
PDBTitle: crystal structure of lck sh2-sh3 with sh2 binding site of2 p130cas
16 c2dybA_
99.8
32
PDB header: oxidoreductaseChain: A: PDB Molecule: neutrophil cytosol factor 4;
PDBTitle: the crystal structure of human p40(phox)
17 c2dvjA_
99.8
29
PDB header: signaling proteinChain: A: PDB Molecule: v-crk sarcoma virus ct10 oncogene homolog,
PDBTitle: phosphorylated crk-ii
18 c2cubA_
99.8
23
PDB header: signaling proteinChain: A: PDB Molecule: cytoplasmic protein nck1;
PDBTitle: solution structure of the sh3 domain of the human2 cytoplasmic protein nck1
19 c1y57A_
99.8
32
PDB header: transferaseChain: A: PDB Molecule: proto-oncogene tyrosine-protein kinase src;
PDBTitle: structure of unphosphorylated c-src in complex with an inhibitor
20 c2h8hA_
99.8
32
PDB header: transferaseChain: A: PDB Molecule: proto-oncogene tyrosine-protein kinase src;
PDBTitle: src kinase in complex with a quinazoline inhibitor
21 d1ov3a2
not modelled
99.8
25
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
22 c3nmzD_
not modelled
99.8
36
PDB header: cell adhesion/cell cycleChain: D: PDB Molecule: rho guanine nucleotide exchange factor 4;
PDBTitle: crytal structure of apc complexed with asef
23 c2fpeB_
not modelled
99.8
25
PDB header: signaling proteinChain: B: PDB Molecule: c-jun-amino-terminal kinase interacting protein
PDBTitle: conserved dimerization of the ib1 src-homology 3 domain
24 c2dmoA_
not modelled
99.8
29
PDB header: signaling proteinChain: A: PDB Molecule: neutrophil cytosol factor 2;
PDBTitle: refined solution structure of the 1st sh3 domain from human2 neutrophil cytosol factor 2 (ncf-2)
25 c2ed0A_
not modelled
99.8
25
PDB header: signaling proteinChain: A: PDB Molecule: abl interactor 2;
PDBTitle: solution structure of the sh3 domain of abl interactor 22 (abelson interactor 2)
26 c2df6A_
not modelled
99.8
33
PDB header: signaling proteinChain: A: PDB Molecule: rho guanine nucleotide exchange factor 7;
PDBTitle: crystal structure of the sh3 domain of betapix in complex2 with a high affinity peptide from pak2
27 c2ablA_
not modelled
99.8
37
PDB header: transferaseChain: A: PDB Molecule: abl tyrosine kinase;
PDBTitle: sh3-sh2 domain fragment of human bcr-abl tyrosine kinase
28 c2yunA_
not modelled
99.8
37
PDB header: protein transportChain: A: PDB Molecule: nostrin;
PDBTitle: solution structure of the sh3 domain of human nostrin
29 d1sema_
not modelled
99.8
41
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
30 c2xmfA_
not modelled
99.8
37
PDB header: motor proteinChain: A: PDB Molecule: myosin 1e sh3;
PDBTitle: myosin 1e sh3
31 c1zx6A_
not modelled
99.8
38
PDB header: protein bindingChain: A: PDB Molecule: ypr154wp;
PDBTitle: high-resolution crystal structure of yeast pin3 sh3 domain
32 c2yuoA_
not modelled
99.8
33
PDB header: signaling proteinChain: A: PDB Molecule: run and tbc1 domain containing 3;
PDBTitle: solution structure of the sh3 domain of mouse run and tbc12 domain containing 3
33 c2yt6A_
not modelled
99.8
28
PDB header: cell cycleChain: A: PDB Molecule: adult male urinary bladder cdna, riken full-
PDBTitle: solution structure of the sh3_1 domain of yamaguchi sarcoma2 viral (v-yes) oncogene homolog 1
34 c2rqrA_
not modelled
99.8
13
PDB header: protein bindingChain: A: PDB Molecule: engulfment and cell motility protein 1, linker, dedicator
PDBTitle: the solution structure of human dock2 sh3 domain - elmo1 peptide2 chimera complex
35 d1utia_
not modelled
99.8
96
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
36 c2bz8B_
not modelled
99.8
25
PDB header: sh3 domainChain: B: PDB Molecule: sh3-domain kinase binding protein 1;
PDBTitle: n-terminal sh3 domain of cin85 bound to cbl-b peptide
37 d1gria2
not modelled
99.8
46
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
38 d1oeba_
not modelled
99.8
92
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
39 c2dlpA_
not modelled
99.8
27
PDB header: structural proteinChain: A: PDB Molecule: kiaa1783 protein;
PDBTitle: solution structure of the sh3 domain of human kiaa17832 protein
40 c3nhnA_
not modelled
99.8
38
PDB header: transferaseChain: A: PDB Molecule: tyrosine-protein kinase hck;
PDBTitle: crystal structure of the src-family kinase hck sh3-sh2-linker2 regulatory region
41 c2dl4A_
not modelled
99.8
30
PDB header: signaling proteinChain: A: PDB Molecule: protein stac;
PDBTitle: solution structure of the first sh3 domain of stac protein
42 d1gcqa_
not modelled
99.8
48
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
43 c1x2qA_
not modelled
99.8
41
PDB header: signaling proteinChain: A: PDB Molecule: signal transducing adapter molecule 2;
PDBTitle: solution structure of the sh3 domain of the signal2 transducing adaptor molecule 2
44 d1uuea_
not modelled
99.8
29
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
45 d1wlpb2
not modelled
99.8
28
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
46 c2nwmA_
not modelled
99.8
36
PDB header: cell adhesionChain: A: PDB Molecule: vinexin;
PDBTitle: solution structure of the first sh3 domain of human vinexin2 and its interaction with the peptides from vinculin
47 c2dilA_
not modelled
99.8
28
PDB header: cell adhesionChain: A: PDB Molecule: proline-serine-threonine phosphatase-interacting
PDBTitle: solution structure of the sh3 domain of the human proline-2 serine-threonine phosphatase-interacting protein 1
48 c2ct3A_
not modelled
99.8
32
PDB header: signaling proteinChain: A: PDB Molecule: vinexin;
PDBTitle: solution structure of the sh3 domain of the vinexin protein
49 c2djqA_
not modelled
99.8
23
PDB header: structural genomics, unknown functionChain: A: PDB Molecule: sh3 domain containing ring finger 2;
PDBTitle: the solution structure of the first sh3 domain of mouse sh32 domain containing ring finger 2
50 c2oi3A_
not modelled
99.8
29
PDB header: transferaseChain: A: PDB Molecule: tyrosine-protein kinase hck;
PDBTitle: nmr structure analysis of the hematopoetic cell kinase sh32 domain complexed with an artificial high affinity ligand3 (pd1)
51 d1pwta_
not modelled
99.8
28
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
52 c2pqhA_
not modelled
99.8
28
PDB header: structural proteinChain: A: PDB Molecule: spectrin alpha chain, brain;
PDBTitle: structure of sh3 chimera with a type ii ligand linked to the chain c-2 terminal
53 c2csqA_
not modelled
99.8
24
PDB header: endocytosis/exocytosisChain: A: PDB Molecule: rim binding protein 2;
PDBTitle: solution structure of the second sh3 domain of human rim-2 binding protein 2
54 c2dl3A_
not modelled
99.8
29
PDB header: cell adhesion, signaling proteinChain: A: PDB Molecule: sorbin and sh3 domain-containing protein 1;
PDBTitle: solution structure of the first sh3 domain of human sorbin2 and sh3 domain-containing protein 1
55 d1k4us_
not modelled
99.8
29
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
56 c2l0aA_
not modelled
99.8
46
PDB header: signaling proteinChain: A: PDB Molecule: signal transducing adapter molecule 1;
PDBTitle: solution nmr structure of signal transducing adapter molecule 1 stam-12 from homo sapiens, northeast structural genomics consortium target3 hr4479e
57 d1udla_
not modelled
99.8
30
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
58 c2kymA_
not modelled
99.8
31
PDB header: signaling proteinChain: A: PDB Molecule: bud emergence protein 1;
PDBTitle: solution structure of the bem1p sh3-ci domain from l.elongisporus in2 complex with ste20p peptide
59 c2cudA_
not modelled
99.8
18
PDB header: signaling proteinChain: A: PDB Molecule: src-like-adapter;
PDBTitle: solution structure of the sh3 domain of the human src-like2 adopter protein (slap)
60 c2epdA_
not modelled
99.8
24
PDB header: protein bindingChain: A: PDB Molecule: rho gtpase-activating protein 4;
PDBTitle: solution structure of sh3 domain in rho-gtpase-activating2 protein 4
61 c2ysqA_
not modelled
99.8
32
PDB header: signaling proteinChain: A: PDB Molecule: rho guanine nucleotide exchange factor 9;
PDBTitle: solution structure of the sh3 domain from rho guanine2 nucleotide exchange factor 9
62 d1j3ta_
not modelled
99.8
25
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
63 c2dnuA_
not modelled
99.8
25
PDB header: structural genomics, structural proteinChain: A: PDB Molecule: sh3 multiple domains 1;
PDBTitle: solution structure of rsgi ruh-061, a sh3 domain from human
64 c2jxbA_
not modelled
99.8
24
PDB header: signaling protein complexChain: A: PDB Molecule: t-cell surface glycoprotein cd3 epsilon chain,
PDBTitle: structure of cd3epsilon-nck2 first sh3 domain complex
65 c2ebpA_
not modelled
99.8
26
PDB header: cell adhesionChain: A: PDB Molecule: sam and sh3 domain-containing protein 1;
PDBTitle: solution structure of the sh3 domain from human sam and sh32 domain containing protein 1
66 d1e6ga_
not modelled
99.8
26
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
67 d1u06a1
not modelled
99.8
29
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
68 d1ue9a_
not modelled
99.8
23
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
69 c2drmB_
not modelled
99.8
40
PDB header: contractile proteinChain: B: PDB Molecule: acanthamoeba myosin ib;
PDBTitle: acanthamoeba myosin i sh3 domain bound to acan125
70 c1wi7A_
not modelled
99.8
27
PDB header: protein bindingChain: A: PDB Molecule: sh3-domain kinase binding protein 1;
PDBTitle: solution structure of the sh3 domain of sh3-domain kinase2 binding protein 1
71 c1x69A_
not modelled
99.8
29
PDB header: signaling proteinChain: A: PDB Molecule: cortactin isoform a;
PDBTitle: solution structures of the sh3 domain of human src2 substrate cortactin
72 c2eyxA_
not modelled
99.8
24
PDB header: signaling proteinChain: A: PDB Molecule: v-crk sarcoma virus ct10 oncogene homolog
PDBTitle: c-terminal sh3 domain of ct10-regulated kinase
73 c2azsA_
not modelled
99.8
46
PDB header: signaling proteinChain: A: PDB Molecule: sh2-sh3 adapter protein drk;
PDBTitle: nmr structure of the n-terminal sh3 domain of drk2 (calculated without noe restraints)
74 d1nega_
not modelled
99.8
28
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
75 c1negA_
not modelled
99.8
28
PDB header: structural proteinChain: A: PDB Molecule: spectrin alpha chain, brain;
PDBTitle: crystal structure analysis of n-and c-terminal labeled sh3-2 domain of alpha-chicken spectrin
76 d1ujya_
not modelled
99.8
27
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
77 c2dl8A_
not modelled
99.8
24
PDB header: signaling proteinChain: A: PDB Molecule: slit-robo rho gtpase-activating protein 2;
PDBTitle: solution structure of the sh3 domain of human slit-robo rho2 gtpase-activating protein 2
78 c2ekhA_
not modelled
99.8
20
PDB header: signaling proteinChain: A: PDB Molecule: sh3 and px domain-containing protein 2a;
PDBTitle: solution structures of the sh3 domain of human kiaa0418
79 c1x2pA_
not modelled
99.7
25
PDB header: transferaseChain: A: PDB Molecule: protein arginine n-methyltransferase 2;
PDBTitle: solution structure of the sh3 domain of the protein2 arginine n-methyltransferase 2
80 c2dbmA_
not modelled
99.7
35
PDB header: transferase, signaling proteinChain: A: PDB Molecule: sh3-containing grb2-like protein 2;
PDBTitle: solution structures of the sh3 domain of human sh3-2 containing grb2-like protein 2
81 c2egeA_
not modelled
99.7
23
PDB header: structural genomics, unknown functionChain: A: PDB Molecule: uncharacterized protein kiaa1666;
PDBTitle: solution structure of the third sh3 domain from human2 kiaa1666 protein
82 c1w70A_
not modelled
99.7
32
PDB header: sh3 domainChain: A: PDB Molecule: neutrophil cytosol factor 4;
PDBTitle: sh3 domain of p40phox complexed with c-terminal polyproline2 region of p47phox
83 d1e6ha_
not modelled
99.7
24
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
84 c2dbkA_
not modelled
99.7
20
PDB header: signaling proteinChain: A: PDB Molecule: crk-like protein;
PDBTitle: solution structures of the sh3 domain of human crk-like2 protein
85 c2egaA_
not modelled
99.7
22
PDB header: signaling proteinChain: A: PDB Molecule: sh3 and px domain-containing protein 2a;
PDBTitle: solution structure of the first sh3 domain from human2 kiaa0418 protein
86 d1h8ka_
not modelled
99.7
25
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
87 c1zlmA_
not modelled
99.7
45
PDB header: signaling proteinChain: A: PDB Molecule: osteoclast stimulating factor 1;
PDBTitle: crystal structure of the sh3 domain of human osteoclast2 stimulating factor
88 c2e5kA_
not modelled
99.7
21
PDB header: protein bindingChain: A: PDB Molecule: suppressor of t-cell receptor signaling 1;
PDBTitle: solution structure of sh3 domain in suppressor of t-cell2 receptor signaling 1
89 c1x43A_
not modelled
99.7
27
PDB header: endocytosis/exocytosisChain: A: PDB Molecule: sh3 domain grb2-like protein b1;
PDBTitle: solution structure of the sh3 domain of endophilin b12 (sh3g1b1)
90 c1x6bA_
not modelled
99.7
22
PDB header: signaling proteinChain: A: PDB Molecule: rho guanine exchange factor (gef) 16;
PDBTitle: solution structures of the sh3 domain of human rho guanine2 exchange factor (gef) 16
91 c3rnjA_
not modelled
99.7
20
PDB header: protein bindingChain: A: PDB Molecule: brain-specific angiogenesis inhibitor 1-associated protein
PDBTitle: crystal structure of the sh3 domain from irsp53 (baiap2)
92 c2krnA_
not modelled
99.7
38
PDB header: signaling proteinChain: A: PDB Molecule: cd2-associated protein;
PDBTitle: high resolution structure of the second sh3 domain of cd2ap
93 c2i0nA_
not modelled
99.7
25
PDB header: structural proteinChain: A: PDB Molecule: class vii unconventional myosin;
PDBTitle: structure of dictyostelium discoideum myosin vii sh3 domain2 with adjacent proline rich region
94 c2yupA_
not modelled
99.7
26
PDB header: cell adhesionChain: A: PDB Molecule: vinexin;
PDBTitle: solution structure of the second sh3 domain of human vinexin
95 c2d1xD_
not modelled
99.7
37
PDB header: cell invasionChain: D: PDB Molecule: cortactin isoform a;
PDBTitle: the crystal structure of the cortactin-sh3 domain and amap1-2 peptide complex
96 c2ed1A_
not modelled
99.7
33
PDB header: signaling proteinChain: A: PDB Molecule: 130 kda phosphatidylinositol 4,5-biphosphate-
PDBTitle: solution structure of the sh3 domain of 130 kda2 phosphatidylinositol 4,5-biphosphate-dependent arf1 gtpase-3 activating protein
97 d1ov3a1
not modelled
99.7
29
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
98 c1x6gA_
not modelled
99.7
18
PDB header: signaling proteinChain: A: PDB Molecule: megakaryocyte-associated tyrosine-protein kinase;
PDBTitle: solution structures of the sh3 domain of human2 megakaryocyte-associated tyrosine-protein kinase.
99 c2eqiA_
not modelled
99.7
30
PDB header: immune system, hydrolaseChain: A: PDB Molecule: phospholipase c, gamma 2;
PDBTitle: solution structure of the sh3 domain from phospholipase c,2 gamma 2
100 d1uhfa_
not modelled
99.7
32
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
101 c2cucA_
not modelled
99.7
30
PDB header: signaling proteinChain: A: PDB Molecule: sh3 domain containing ring finger 2;
PDBTitle: solution structure of the sh3 domain of the mouse2 hypothetical protein sh3rf2
102 c2o2oA_
not modelled
99.7
27
PDB header: protein bindingChain: A: PDB Molecule: sh3-domain kinase-binding protein 1;
PDBTitle: solution structure of domain b from human cin85 protein
103 c2rf0D_
not modelled
99.7
45
PDB header: transferaseChain: D: PDB Molecule: mitogen-activated protein kinase kinase kinase 10;
PDBTitle: crystal structure of human mixed lineage kinase map3k10 sh3 domain
104 c1wyxA_
not modelled
99.7
36
PDB header: cell adhesionChain: A: PDB Molecule: crk-associated substrate;
PDBTitle: the crystal structure of the p130cas sh3 domain at 1.1 a2 resolution
105 d1uj0a_
not modelled
99.7
56
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
106 d1wfwa_
not modelled
99.7
22
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
107 c1g83A_
not modelled
99.7
37
PDB header: transferaseChain: A: PDB Molecule: proto-oncogene tyrosine-protein kinase fyn;
PDBTitle: crystal structure of fyn sh3-sh2
108 c2kbtA_
not modelled
99.7
32
PDB header: signaling proteinChain: A: PDB Molecule: chimera of proto-oncogene vav, linker,
PDBTitle: attachment of an nmr-invisible solubility enhancement tag2 (inset) using a sortase-mediated protein ligation method
109 c2dl7A_
not modelled
99.7
30
PDB header: structural genomics, unknown functionChain: A: PDB Molecule: kiaa0769 protein;
PDBTitle: solution structure of the second sh3 domain of human2 kiaa0769 protein
110 c1zukA_
not modelled
99.7
21
PDB header: contractile proteinChain: A: PDB Molecule: myosin tail region-interacting protein mti1;
PDBTitle: yeast bbc1 sh3 domain complexed with a peptide from las17
111 c1bb9A_
not modelled
99.7
28
PDB header: transferaseChain: A: PDB Molecule: amphiphysin 2;
PDBTitle: crystal structure of the sh3 domain from rat amphiphysin 2
112 d1bb9a_
not modelled
99.7
28
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
113 c3qwxX_
not modelled
99.7
25
PDB header: signaling proteinChain: X: PDB Molecule: cell death abnormality protein 2;
PDBTitle: ced-2 1-174
114 c3cqtA_
not modelled
99.7
44
PDB header: transferaseChain: A: PDB Molecule: proto-oncogene tyrosine-protein kinase fyn;
PDBTitle: n53i v55l mutant of fyn sh3 domain
115 c3qwyA_
not modelled
99.7
26
PDB header: signaling proteinChain: A: PDB Molecule: cell death abnormality protein 2;
PDBTitle: ced-2
116 d1ug1a_
not modelled
99.7
18
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
117 c2j6kE_
not modelled
99.7
27
PDB header: protein bindingChain: E: PDB Molecule: cd2-associated protein;
PDBTitle: n-terminal sh3 domain of cms (cd2ap human homolog)
118 c2jteA_
not modelled
99.7
31
PDB header: signaling proteinChain: A: PDB Molecule: cd2-associated protein;
PDBTitle: third sh3 domain of cd2ap
119 d1uhca_
not modelled
99.7
24
Fold: SH3-like barrelSuperfamily: SH3-domainFamily: SH3-domain
120 c2ke9A_
not modelled
99.7
29
PDB header: protein bindingChain: A: PDB Molecule: caskin-2;
PDBTitle: nmr solution structure of the caskin sh3 domain