Annotations: 1SQK

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1sqka1	Alpha and beta proteins (a/b)	Ribonuclease H-like motif	Actin-like ATPase domain	Actin/HSP70	Actin	(Oryctolagus cuniculus ) [TaxId: 9986 ],	SCOPe (2.08)
B	d1sqkb_	Peptides	Actin-binding peptides	Actin-binding peptides	Actin-binding peptides	Ciboulot	fruit fly (Drosophila melanogaster ) [TaxId: 7227 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Actin-like ATPases	8040506	3000092	SCOP2B (2022-06-29)
A	SCOP2B Superfamily	Actin-like ATPases	8040509	3000092	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A		e1sqkA1	A: C-terminal subdomain in Lon-related proteases catalytic domains	X: C-terminal subdomain in Lon-related proteases catalytic domains	H: C-terminal subdomain in Lon-related proteases catalytic domains	T: Hexokinase_2	F:	ECOD (20:10:01)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.30.420.40	Alpha Beta	2-Layer Sandwich	Nucleotidyltransferase	domain 5	CATH (4.3.0)
A	2.30.36.70	Mainly Beta	Roll	Actin	Chain A, domain 2	CATH (4.3.0)
A	3.90.640.10	Alpha Beta	Alpha-Beta Complex	Actin	Chain A, domain 4	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
B	PF01290	Thymosin beta-4 family (Thymosin)	Thymosin beta-4 family	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	ACTIN, ALPHA SKELETAL MUSCLE	cytoskeletal protein binding titin binding protein binding binding cation binding ion binding calcium ion binding metal ion binding small molecule binding protein domain specific binding hydrolase activity catalytic activity troponin I binding cytoskeletal motor activator activity cytoskeletal protein binding titin binding protein binding binding cation binding ion binding calcium ion binding metal ion binding small molecule binding protein domain specific binding hydrolase activity catalytic activity troponin I binding cytoskeletal motor activator activity cytoskeletal motor regulator activity molecular function activator activity molecular function regulator activity magnesium ion binding adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding purine nucleotide binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding myosin heavy chain binding myosin binding tropomyosin binding calcium-dependent protein binding identical protein binding actin monomer binding actin binding	developmental process mesenchyme migration multicellular organismal process mesenchyme morphogenesis animal organ development mesenchyme development tissue development tissue morphogenesis anatomical structure morphogenesis tissue migration anatomical structure development animal organ morphogenesis myotube cell development skeletal muscle fiber development developmental process mesenchyme migration multicellular organismal process mesenchyme morphogenesis animal organ development mesenchyme development tissue development tissue morphogenesis anatomical structure morphogenesis tissue migration anatomical structure development animal organ morphogenesis myotube cell development skeletal muscle fiber development cellular developmental process skeletal muscle tissue development cell development muscle cell differentiation myotube differentiation striated muscle tissue development muscle structure development skeletal muscle organ development striated muscle cell development muscle cell development cell differentiation cellular process muscle tissue development muscle organ development striated muscle cell differentiation regulation of biosynthetic process regulation of biological process regulation of cellular process biological regulation positive regulation of biological process regulation of macromolecule metabolic process gene expression macromolecule biosynthetic process positive regulation of macromolecule biosynthetic process regulation of gene expression positive regulation of metabolic process biosynthetic process positive regulation of gene expression positive regulation of biosynthetic process regulation of macromolecule biosynthetic process metabolic process positive regulation of macromolecule metabolic process macromolecule metabolic process regulation of metabolic process positive regulation of cellular process cellular component assembly involved in morphogenesis skeletal myofibril assembly membraneless organelle assembly cellular component organization cellular component biogenesis cellular anatomical entity morphogenesis cellular component assembly actin filament-based process cellular component organization or biogenesis skeletal muscle thin filament assembly actin cytoskeleton organization actomyosin structure organization organelle assembly actin filament organization organelle organization myofibril assembly anatomical structure formation involved in morphogenesis supramolecular fiber organization cytoskeleton organization protein polymerization actin polymerization or depolymerization actin filament polymerization protein-containing complex organization protein-containing complex assembly actin filament bundle organization actin filament bundle assembly	intracellular anatomical structure skeletal muscle myofibril intracellular membraneless organelle intracellular organelle cellular anatomical structure organelle membraneless organelle contractile muscle fiber cytoplasm supramolecular fiber myofibril supramolecular polymer supramolecular complex cell projection intracellular anatomical structure skeletal muscle myofibril intracellular membraneless organelle intracellular organelle cellular anatomical structure organelle membraneless organelle contractile muscle fiber cytoplasm supramolecular fiber myofibril supramolecular polymer supramolecular complex cell projection cell leading edge plasma membrane bounded cell projection lamellipodium cytoskeleton actin filament bundle actin cytoskeleton actomyosin stress fiber contractile actin filament bundle polymeric cytoskeletal fiber actin filament protein-containing complex filamentous actin cell body striated muscle thin filament myofilament sarcomere actin-based cell projection filopodium
B	CIBOULOT	cytoskeletal protein binding actin monomer binding actin binding protein binding binding	developmental process multicellular organism development multicellular organismal process head development central nervous system development anatomical structure development animal organ development brain development nervous system development system development cellular component organization organelle organization actin cytoskeleton organization actin filament organization developmental process multicellular organism development multicellular organismal process head development central nervous system development anatomical structure development animal organ development brain development nervous system development system development cellular component organization organelle organization actin cytoskeleton organization actin filament organization actin filament-based process cellular process cellular component organization or biogenesis supramolecular fiber organization cytoskeleton organization larval central nervous system remodeling instar larval or pupal development anatomical structure morphogenesis post-embryonic animal morphogenesis post-embryonic development	cellular anatomical structure intracellular anatomical structure cytoplasm cytosol intracellular organelle cytoskeleton organelle membraneless organelle intracellular membraneless organelle

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR020902	Actin/actin-like conserved site	Conserved Site
A	IPR043129	ATPase, nucleotide binding domain	Homologous Superfamily
A	IPR004001	Actin, conserved site	Conserved Site
A	IPR004000	Actin family	Family
B	IPR038386	Beta-thymosin superfamily	Homologous Superfamily
B	IPR001152	Beta-thymosin	Family

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729. RCSB PDB uses resources of the National Energy Research Scientific Computing Center (NERSC), a Department of Energy User Facility.