Annotations: 2Y1Y

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Hsp20 chaperone-like	8089917	3001242	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	HSP20	e2y1yA1	A: beta sandwiches	X: HSP20-like	H: HSP20-like chaperones (From Topology)	T: HSP20-like chaperones	F: HSP20	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	2.60.40.790	Mainly Beta	Sandwich	Immunoglobulin-like		CATH (4.3.0)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	ALPHA-CRYSTALLIN B CHAIN,	amide binding amyloid-beta binding binding peptide binding cytoskeletal protein binding microtubule binding protein binding tubulin binding protein-containing complex binding cation binding ion binding metal ion binding small molecule binding identical protein binding amide binding amyloid-beta binding binding peptide binding cytoskeletal protein binding microtubule binding protein binding tubulin binding protein-containing complex binding cation binding ion binding metal ion binding small molecule binding identical protein binding unfolded protein binding protein homodimerization activity protein dimerization activity structural molecule activity structural constituent of eye lens	protein refolding primary metabolic process gene expression macromolecule biosynthetic process protein maturation protein folding biosynthetic process metabolic process cellular process protein metabolic process macromolecule metabolic process regulation of protein stability biological regulation regulation of biological quality protein refolding primary metabolic process gene expression macromolecule biosynthetic process protein maturation protein folding biosynthetic process metabolic process cellular process protein metabolic process macromolecule metabolic process regulation of protein stability biological regulation regulation of biological quality protein stabilization tubulin complex assembly cellular component organization cellular component biogenesis cellular component assembly protein-containing complex organization protein-containing complex assembly cellular component organization or biogenesis developmental process multicellular organismal process sensory organ development eye development animal organ development visual system development multicellular organism development camera-type eye development anatomical structure development sensory system development lens development in camera-type eye system development negative regulation of intracellular transport regulation of localization cellular localization regulation of biological process regulation of cellular process transport regulation of transport negative regulation of biological process intracellular transport negative regulation of transport establishment of localization localization regulation of cellular localization establishment of localization in cell negative regulation of cellular process regulation of intracellular transport muscle structure development muscle organ development regulation of growth regulation of cellular component organization growth negative regulation of cell growth regulation of cell growth cell growth negative regulation of growth negative regulation of cellular component organization regulation of cellular component biogenesis negative regulation of protein-containing complex assembly regulation of protein-containing complex assembly negative regulation of metabolic process reactive oxygen species metabolic process negative regulation of reactive oxygen species metabolic process regulation of metabolic process regulation of reactive oxygen species metabolic process response to decreased oxygen levels response to stimulus response to hypoxia response to stress response to oxygen levels response to abiotic stimulus system process muscle contraction muscle system process response to hydrogen peroxide response to oxidative stress response to chemical response to oxygen-containing compound response to reactive oxygen species response to heat response to temperature stimulus apoptotic process involved in development anatomical structure morphogenesis apoptotic process involved in morphogenesis apoptotic process cell death programmed cell death RNA metabolic process regulation of primary metabolic process negative regulation of RNA biosynthetic process RNA biosynthetic process nucleobase-containing compound metabolic process DNA-templated transcription nucleic acid biosynthetic process regulation of RNA metabolic process negative regulation of nucleobase-containing compound metabolic process regulation of nucleobase-containing compound metabolic process regulation of RNA biosynthetic process negative regulation of macromolecule metabolic process regulation of biosynthetic process negative regulation of DNA-templated transcription regulation of macromolecule metabolic process nucleobase-containing compound biosynthetic process nucleic acid metabolic process regulation of gene expression negative regulation of biosynthetic process negative regulation of macromolecule biosynthetic process regulation of macromolecule biosynthetic process regulation of DNA-templated transcription negative regulation of RNA metabolic process organelle organization microtubule polymerization or depolymerization microtubule cytoskeleton organization microtubule-based process cytoskeleton organization cellular response to stimulus signaling intracellular signal transduction cell communication stress-activated MAPK cascade stress-activated protein kinase signaling cascade cellular response to stress intracellular signaling cassette MAPK cascade signal transduction cellular response to ionizing radiation cellular response to radiation cellular response to environmental stimulus response to ionizing radiation cellular response to gamma radiation response to radiation cellular response to abiotic stimulus response to gamma radiation negative regulation of programmed cell death regulation of apoptotic process regulation of programmed cell death negative regulation of apoptotic process negative regulation of gene expression negative regulation of amyloid fibril formation regulation of amyloid fibril formation amyloid fibril formation negative regulation of supramolecular fiber organization negative regulation of protein metabolic process regulation of protein metabolic process regulation of supramolecular fiber organization supramolecular fiber organization response to lipid response to estradiol response to organic cyclic compound	somatodendritic compartment cell body cellular anatomical structure perikaryon neuronal cell body M band intracellular anatomical structure intracellular membraneless organelle sarcomere intracellular organelle organelle membraneless organelle contractile muscle fiber A band somatodendritic compartment cell body cellular anatomical structure perikaryon neuronal cell body M band intracellular anatomical structure intracellular membraneless organelle sarcomere intracellular organelle organelle membraneless organelle contractile muscle fiber A band cytoplasm supramolecular fiber myofibril supramolecular polymer supramolecular complex Z disc I band extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle extracellular region extracellular space vesicle extracellular membrane-bounded organelle cytosol neuron spine synapse neuron projection dendritic spine plasma membrane bounded cell projection cell projection postsynapse cell junction dendrite dendritic tree axon mitochondrion intracellular membrane-bounded organelle cell periphery membrane plasma membrane plasma membrane region synaptic membrane cell surface nucleus membrane-enclosed lumen intracellular organelle lumen nucleoplasm organelle lumen nuclear lumen lytic vacuole vacuole lysosome protein-containing complex cytoskeleton actin filament bundle actin cytoskeleton cardiac myofibril

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR003090	Alpha-crystallin, N-terminal	Domain
A	IPR001436	Alpha crystallin/Small heat shock protein, animal type	Family
A	IPR002068	Alpha crystallin/Hsp20 domain	Domain
A	IPR008978	HSP20-like chaperone	Homologous Superfamily
A	IPR037882	Alpha-crystallin B chain, ACD domain	Domain

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A	Pharos: P02511	myofibrillar myopathy 2 dilated cardiomyopathy 1II fatal infantile hypertonic myofibrillar myopathy dilated cardiomyopathy malignant colon neoplasm squamous cell carcinoma renal cell carcinoma cataract cataract 16 multiple types Liver Cirrhosis, Experimental cardiomyopathy chromophobe renal cell carcinoma myopathy papillary renal cell carcinoma esophageal cancer myofibrillar myopathy 2 dilated cardiomyopathy 1II fatal infantile hypertonic myofibrillar myopathy dilated cardiomyopathy malignant colon neoplasm squamous cell carcinoma renal cell carcinoma cataract cataract 16 multiple types Liver Cirrhosis, Experimental cardiomyopathy chromophobe renal cell carcinoma myopathy papillary renal cell carcinoma esophageal cancer prostate cancer hypertrophic cardiomyopathy sarcomatoid renal cell carcinoma collecting duct carcinoma neurodegenerative disease cystic fibrosis nuclear cataract ovarian cancer Down syndrome pancreatic intraductal papillary-mucinous neoplasm with low grade dysplasia arthrogryposis esophageal adenocarcinoma atypical teratoid rhabdoid tumor familial isolated dilated cardiomyopathy breast cancer invasive ductal breast carcinoma renal carcinoma medulloblastoma muscular disease colonic neoplasm pancreatic intraductal papillary-mucinous carcinoma ductal breast carcinoma in situ astrocytic tumor Barrett esophagus large cell medulloblastoma breast carcinoma lung adenocarcinoma tongue cancer clear cell renal carcinoma myofibrillar myopathy neoplasm of esophagus non-small cell lung carcinoma oral cavity neoplasm distal myopathy pancreatic intraductal papillary-mucinous neoplasm endometriosis pituitary cancer atopic eczema familial dilated cardiomyopathy benign colon neoplasm psoriasis breast fibroadenoma lung cancer Charcot-Marie-Tooth disease muscle tissue disease

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.