9rfb

Crystal Structure of Human Rac1 in Complex with the Scaffold Protein POSH (residues 321-348)

Method: X-RAY DIFFRACTION

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

Ras-related C3 botulinum toxin substrate 1

Homo sapiens

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 2	E3 ubiquitin-protein ligase SH3RF1 × 1 （Q7Z6J0） PHOSPHOAMINOPHOSPHONIC ACID-GUANYLATE ESTER × 1 MAGNESIUM ION × 1 water × 2	Consistent with protein count
2	Protein heterocomplex	Heteromer	Protein 2	E3 ubiquitin-protein ligase SH3RF1 × 1 （Q7Z6J0） PHOSPHOAMINOPHOSPHONIC ACID-GUANYLATE ESTER × 1 MAGNESIUM ION × 1 PHOSPHATE ION × 2 CHLORIDE ION × 1 water × 2	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	RAC1_HUMAN
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 4–180； UniProt 1–177 Author chain B； PDBConstruct 4–180； UniProt 1–177

E3 ubiquitin-protein ligase SH3RF1

OrganismNot specified

UniProt Q7Z6J0

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Protein heterocomplex	Heteromer	Protein 2	Ras-related C3 botulinum toxin substrate 1 × 1 （P63000） PHOSPHOAMINOPHOSPHONIC ACID-GUANYLATE ESTER × 1 MAGNESIUM ION × 1 water × 2	Consistent with protein count
2	Protein heterocomplex	Heteromer	Protein 2	Ras-related C3 botulinum toxin substrate 1 × 1 （P63000） PHOSPHOAMINOPHOSPHONIC ACID-GUANYLATE ESTER × 1 MAGNESIUM ION × 1 PHOSPHATE ION × 2 CHLORIDE ION × 1 water × 2	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	SH3R1_HUMAN
Isoform	—
PDB entities	2
Chains and sequence ranges	Author chain C； PDBConstruct 1–28； UniProt 321–348 Author chain D； PDBConstruct 1–28； UniProt 321–348

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	9rfb
Deposition date deposition_date	2025-06-04
Structure title title	Crystal Structure of Human Rac1 in Complex with the Scaffold Protein POSH (residues 321-348)
Keywords keywords	GTPase GTP/GDP-Binding Nucleotide binding, HYDROLASE; HYDROLASE
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.

9rfb__assembly_1__model_1

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

Download this curve (.dat)

9rfb__assembly_1__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

9rfb__assembly_1__model_1 | P(r) · Pending

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

Rg（Guinier）	17.32 Å
Rg (electron density)	16.30 Å
Total Rg	17.36 Å
Atom count	1571
Residues	199
Excluded volume	28124 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`9rfb__assembly_1__model_1`	dimeric （2）	Success	4.1.3-1-20251215 (887e7ef)	View Download
2	1	`9rfb__assembly_2__model_1`	dimeric （2）	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 (7)

Entity 1 Entity 1 polymer

Description description	Ras-related C3 botulinum toxin substrate 1
Molecular weight formula_weight	20158.3 kDa
EC 编号 ec_number	3.6.5.2
Source method src_method	man
Copy count entity_count	2

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A,B
Atom count atom_count	3571

GRRMQAIKCVVVGDGAVGKTCLLISYTTNAFPGEYIPTVFDNYSANVMVDGKPVNLGLWDTAGQEDYDRLRPLSYPQTDVFLICFSLVSPASFENVRAKWYPEVRHHCPNTPIILVGTKLDLRDDKDTIEKLKEKKLTPITYPQGLAMAKEIGAVKYLECSALTQRGLKTVFDEAIRAVL

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

Entity 2 Entity 2 polymer

Description description	E3 ubiquitin-protein ligase SH3RF1
Molecular weight formula_weight	2911.3 kDa
EC 编号 ec_number	2.3.2.27
Source method src_method	syn
Copy count entity_count	2

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	C,D

RHSMEISPPVLISSSNPTAAARISELSG

Entity 3 Entity 3 non-polymer

Description description	PHOSPHOAMINOPHOSPHONIC ACID-GUANYLATE ESTER
Molecular weight formula_weight	522.2 kDa
Source method src_method	syn
Copy count entity_count	2

Entity 4 Entity 4 non-polymer

Description description	MAGNESIUM ION
Molecular weight formula_weight	24.3 kDa
Source method src_method	syn
Copy count entity_count	2

Entity 5 Entity 5 non-polymer

Description description	PHOSPHATE ION
Molecular weight formula_weight	95.0 kDa
Source method src_method	syn
Copy count entity_count	2

Entity 6 Entity 6 non-polymer

Description description	CHLORIDE ION
Molecular weight formula_weight	35.5 kDa
Source method src_method	syn
Copy count entity_count	1

Entity 7 Entity 7 water

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	390

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Unit-cell length a length_a	54.793 Å
Unit-cell length b length_b	54.793 Å
Unit-cell length c length_c	329.942 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	90.00 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	16

Space group space_group	P 43 21 2
Space-group number int_tables_number	96
Crystal system crystal_system	—

Resolution resolution	1.854 Å
Low-resolution limit resolution_low	19.670 Å
R factor r_factor	—
R_work r_work	0.1946
R_free r_free	0.2263

Crystal Structure of Human Rac1 in Complex with the Scaffold Protein POSH (residues 321-348)

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

Ras-related C3 botulinum toxin substrate 1

State in the Current Structure

Other States of the Same Protein in the Database

E3 ubiquitin-protein ligase SH3RF1

State in the Current Structure

Other States of the Same Protein in the Database

2. Structure Basics 2. Structure Basics

3. Official assembly/model SAXS Official SAXS Profiles

9rfb__assembly_1__model_1

9rfb__assembly_1__model_1 | I(q)

9rfb__assembly_1__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 (7)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Entity 3 Entity 3 non-polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 non-polymer

Entity 6 Entity 6 non-polymer

Entity 7 Entity 7 water

7. Citations (1)

Crystal Structure of Human Rac1 in Complex with the Scaffold Protein POSH (residues 321-348)

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

Ras-related C3 botulinum toxin substrate 1

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

E3 ubiquitin-protein ligase SH3RF1

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

9rfb__assembly_1__model_1

9rfb__assembly_1__model_1 | I(q)

9rfb__assembly_1__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 (7)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Entity 3 Entity 3 non-polymer

Entity 4 Entity 4 non-polymer

Entity 5 Entity 5 non-polymer

Entity 6 Entity 6 non-polymer

Entity 7 Entity 7 water

7. Citations (1)