2ian

Structural basis for recognition of mutant self by a tumor-specific, MHC class II-restricted TCR

Method: X-RAY DIFFRACTION

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1. Protein Identity and Related Structures Protein Identity & Related Structures

HLA class II histocompatibility antigen, DR alpha chain

Homo sapiens

UniProt P01903

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
2	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
3	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 3	Consistent with protein count
4	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	2DRA_HUMAN
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–182； UniProt 26–207 Author chain F； PDBConstruct 1–182； UniProt 26–207 Author chain K； PDBConstruct 1–182； UniProt 26–207 Author chain P； PDBConstruct 1–182； UniProt 26–207

HLA class II histocompatibility antigen, DRB1-1 beta chain

Homo sapiens

UniProt P04229

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
2	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
3	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 3	Consistent with protein count
4	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	2B11_HUMAN
Isoform	—
PDB entities	2
Chains and sequence ranges	Author chain B； PDBConstruct 1–190； UniProt 30–219 Author chain G； PDBConstruct 1–190； UniProt 30–219 Author chain L； PDBConstruct 1–190； UniProt 30–219 Author chain Q； PDBConstruct 1–190； UniProt 30–219

15-mer peptide from Triosephosphate isomerase

Homo sapiens

UniProt P60174

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
2	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
3	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 3	Consistent with protein count
4	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） CD4+ T cell receptor E8 alpha chain × 1 （P01848） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	TPIS_HUMAN
Isoform	—
PDB entities	3
Chains and sequence ranges	Author chain C； PDBConstruct 1–15； UniProt 22–36 Author chain H； PDBConstruct 1–15； UniProt 22–36 Author chain M； PDBConstruct 1–15； UniProt 22–36 Author chain R； PDBConstruct 1–15； UniProt 22–36

CD4+ T cell receptor E8 alpha chain

Homo sapiens

UniProt P01848

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
2	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count
3	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 3	Consistent with protein count
4	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 beta chain × 1 （P01850） water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	TCA_HUMAN
Isoform	—
PDB entities	4
Chains and sequence ranges	Author chain D； PDBConstruct 108–202； UniProt 1–95 Author chain I； PDBConstruct 108–202； UniProt 1–95 Author chain N； PDBConstruct 108–202； UniProt 1–95 Author chain S； PDBConstruct 108–202； UniProt 1–95

CD4+ T cell receptor E8 beta chain

Homo sapiens

UniProt P01850

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） water × 4	Consistent with protein count
2	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） water × 4	Consistent with protein count
3	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） water × 3	Consistent with protein count
4	Protein heterocomplex	Heteromer	Protein 5	HLA class II histocompatibility antigen, DR alpha chain × 1 （P01903） HLA class II histocompatibility antigen, DRB1-1 beta chain × 1 （P04229） 15-mer peptide from Triosephosphate isomerase × 1 （P60174） CD4+ T cell receptor E8 alpha chain × 1 （P01848） water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	TCB_HUMAN
Isoform	—
PDB entities	5
Chains and sequence ranges	Author chain E； PDBConstruct 111–240； UniProt 1–130 Author chain J； PDBConstruct 111–240； UniProt 1–130 Author chain O； PDBConstruct 111–240； UniProt 1–130 Author chain T； PDBConstruct 111–240； UniProt 1–130

The page prioritizes protein identity, the current assembly, associated components, oligomeric state and cross-PDB links. Chain mapping and sequence ranges are retained as data evidence. Internal IDs, import timestamps and assembly operation expressions are maintenance fields and are not shown here.

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2. Structure Basics 2. Structure Basics

Entry ID entry_id	2ian
Deposition date deposition_date	2006-09-08
Structure title title	Structural basis for recognition of mutant self by a tumor-specific, MHC class II-restricted TCR
Keywords keywords	major histocompatibility complex, T cell receptor, T cell stimulation, melanoma, tumor antigen, IMMUNE SYSTEM; IMMUNE SYSTEM
Experimental Method method	X-RAY DIFFRACTION

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3. Official assembly/model SAXS Official SAXS Profiles

This page reads only the latest assembly calculations. Every curve maps to an explicit PDB entry, official biological assembly and coordinate model.

2ian__assembly_4__model_1

Assembly 4 · Model 1 · CRYSOL 4.1.3-1-20251215 (887e7ef)

Download this curve (.dat)

2ian__assembly_4__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

2ian__assembly_4__model_1 | P(r) · Pending

P(r) will be calculated and displayed separately for the same assembly/model.

Rg（Guinier）	37.07 Å
Rg (electron density)	37.37 Å
Total Rg	37.52 Å
Atom count	6562
Residues	818
Excluded volume	115660 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`2ian__assembly_1__model_1`	pentameric （5）	Success	4.1.3-1-20251215 (887e7ef)	View Download
2	1	`2ian__assembly_2__model_1`	pentameric （5）	Success	4.1.3-1-20251215 (887e7ef)	View Download
3	1	`2ian__assembly_3__model_1`	pentameric （5）	Success	4.1.3-1-20251215 (887e7ef)	View Download
4	1	`2ian__assembly_4__model_1`	pentameric （5）	Success	4.1.3-1-20251215 (887e7ef)	View Download

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4. Crystallography and Experiment 4. Crystallography & Experiment

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5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Description description	HLA class II histocompatibility antigen, DR alpha chain
Molecular weight formula_weight	21155.9 kDa
Source method src_method	man
Copy count entity_count	4

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,F,K,P
Atom count atom_count	26209

IKEEHVIIQAEFYLNPDQSGEFMFDFDGDEIFHVDMAKKETVWRLEEFGRFASFEAQGALANIAVDKANLEIMTKRSNYTPITNVPPEVTVLTNSPVELREPNVLICFIDKFTPPVVNVTWLRNGKPVTTGVSETVFLPREDHLFRKFHYLPFLPSTEDVYDCRVEHWGLDEPLLKHWEFDA

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli BL21

Entity 2 Entity 2 polymer

Description description	HLA class II histocompatibility antigen, DRB1-1 beta chain
Molecular weight formula_weight	22080.7 kDa
Source method src_method	man
Copy count entity_count	4

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	B,G,L,Q

GDTRPRFLWQLKFECHFFNGTERVRLLERCIYNQEESVRFDSDVGEYRAVTELGRPDAEYWNSQKDLLEQRRAAVDTYCRHNYGVGESFTVQRRVEPKVTVYPSKTQPLQHHNLLVCSVSGFYPGSIEVRWFRNGQEEKAGVVSTGLIQNGDWTFQTLVMLETVPRSGEVYTCQVEHPSVTSPLTVEWRA

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli BL21

Entity 3 Entity 3 polymer

Description description	15-mer peptide from Triosephosphate isomerase
Molecular weight formula_weight	1469.7 kDa
EC 编号 ec_number	5.3.1.1
Source method src_method	man
Copy count entity_count	4

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	C,H,M,R

GELIGTLNAAKVPAD

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli BL21

Entity 4 Entity 4 polymer

Description description	CD4+ T cell receptor E8 alpha chain
Molecular weight formula_weight	22399.7 kDa
Mutation mutation	T156C
Source method src_method	man
Copy count entity_count	4

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	D,I,N,S

IQVEQSPPDLILQEGANSTLRCNFSDSVNNLQWFHQNPWGQLINLFYIPSGTKQNGRLSATTVATERYSLLYISSSQTTDSGVYFCAALIQGAQKLVFGQGTRLTINPNIQNPDPAVYQLRDSKSSDKSVCLFTDFDSQTNVSQSKDSDVYITDKCVLDMRSMDFKSNSAVAWSNKSDFACANAFNNSIIPEDTFFPSPESS

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli BL21

Entity 5 Entity 5 polymer

Description description	CD4+ T cell receptor E8 beta chain
Molecular weight formula_weight	27088.2 kDa
Mutation mutation	S167C
Source method src_method	man
Copy count entity_count	4

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	E,J,O,T

NAGVTQTPKFRILKIGQSMTLQCTQDMNHNYMYWYRQDPGMGLKLIYYSVGAGITDKGEVPNGYNVSRSTTEDFPLRLELAAPSQTSVYFCASTYHGTGYFGEGSWLTVVEDLNKVFPPEVAVFEPSEAEISHTQKATLVCLATGFFPDHVELSWWVNGKEVHSGVCTDPQPLKEQPALNDSRYALSSRLRVSATFWQNPRNHFRCQVQFYGLSENDEWTQDRAKPVTQIVSAEAWGRAD

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli BL21

Entity 6 Entity 6 water

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	76

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6. Fold Classification (SCOP + CATH) 65 domains

SCOP 2.08 (33 domains)

Domain ID domain_id	d2iana1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2iana2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2iana3
Class class	l — Artifacts
Fold Fold fold	l.1 — Tags
Superfamily Superfamily superfamily	l.1.1 — Tags
Family Family family	l.1.1.1 — Tags

Domain ID domain_id	d2ianb1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianb2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2iand1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2iand2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2iane1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2iane2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianf1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianf2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2iang1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2iang2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2iani1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2iani2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianj1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2ianj2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2iank1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2iank2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2ianl1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianl2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2iann1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2iann2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2iano1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2iano2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianp1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianp2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2ianq1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2ianq2
Class class	d — Alpha and beta proteins (a+b)
Fold Fold fold	d.19 — MHC antigen-recognition domain
Superfamily Superfamily superfamily	d.19.1 — MHC antigen-recognition domain
Family Family family	d.19.1.1 — MHC antigen-recognition domain

Domain ID domain_id	d2ians1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2ians2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

Domain ID domain_id	d2iant1
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.0 — automated matches

Domain ID domain_id	d2iant2
Class class	b — All beta proteins
Fold Fold fold	b.1 — Immunoglobulin-like beta-sandwich
Superfamily Superfamily superfamily	b.1.1 — Immunoglobulin
Family Family family	b.1.1.2 — C1 set domains (antibody constant domain-like)

CATH v4.4 (32 domains)

Domain ID domain_id	2ianA01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianA02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianB01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianB02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianD01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianD02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianE01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianE02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianF01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianF02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianG01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianG02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianI01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianI02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianJ01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianJ02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianK01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianK02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianL01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianL02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianN01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianN02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianO01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianO02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianP01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianP02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianQ01
Class class	3 — Alpha Beta
Architecture architecture	10 — Roll
Topology topology	320 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1
Homologous superfamily homologous superfamily	10 — Class II Histocompatibility Antigen, M Beta Chain; Chain B, domain 1

Domain ID domain_id	2ianQ02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianS01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianS02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianT01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	2ianT02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

▶

Unit-cell length a length_a	93.474 Å
Unit-cell length b length_b	242.866 Å
Unit-cell length c length_c	105.222 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	111.32 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	8

Space group space_group	P 1 21 1
Space-group number int_tables_number	4
Crystal system crystal_system	—

Resolution resolution	2.800 Å
Low-resolution limit resolution_low	45.450 Å
R factor r_factor	0.2250
R_work r_work	0.2212
R_free r_free	0.2959

Structural basis for recognition of mutant self by a tumor-specific, MHC class II-restricted TCR

1. Protein Identity and Related Structures Protein Identity & Related Structures

HLA class II histocompatibility antigen, DR alpha chain

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

HLA class II histocompatibility antigen, DRB1-1 beta chain

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

15-mer peptide from Triosephosphate isomerase

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

CD4+ T cell receptor E8 alpha chain

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

CD4+ T cell receptor E8 beta chain

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

2. Structure Basics 2. Structure Basics

3. Official assembly/model SAXS Official SAXS Profiles

2ian__assembly_4__model_1

2ian__assembly_4__model_1 | I(q)

2ian__assembly_4__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

Diffraction experiment Diffraction

5. Entities and Polymers Entities & Polymers (6)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Source Source

Entity 3 Entity 3 polymer

Polymer Polymer

Source Source

Entity 4 Entity 4 polymer

Polymer Polymer

Source Source

Entity 5 Entity 5 polymer

Polymer Polymer

Source Source

Entity 6 Entity 6 water

6. Fold Classification (SCOP + CATH) 65 domains

SCOP 2.08 (33 domains)

CATH v4.4 (32 domains)

7. Citations (1)