Annotations: 6U2U

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
B	PSII	e6u2uB1	A: a/b three-layered sandwiches	X: P-loop domains-like	H: DUF1107-like	T: DUF1107-like	F: PSII	ECOD (v294.1)
A	Lipocalin	e6u2uA1	A: a/b three-layered sandwiches	X: P-loop domains-like	H: DUF1107-like	T: DUF1107-like	F: Lipocalin	ECOD (v294.1)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	PF00010	Helix-loop-helix DNA-binding domain (HLH)	Helix-loop-helix DNA-binding domain		Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	DNA-binding protein inhibitor ID-1	molecular function inhibitor activity molecular function regulator activity transcription regulator inhibitor activity transcription corepressor activity transcription regulator activity transcription coregulator activity protein-macromolecule adaptor activity molecular adaptor activity protein-containing complex binding binding proteasome binding protein binding protein dimerization activity identical protein binding	regulation of cellular process negative regulation of biological process 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 cellular process negative regulation of nucleobase-containing compound metabolic process regulation of nucleobase-containing compound metabolic process regulation of RNA biosynthetic process regulation of cellular process negative regulation of biological process 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 cellular 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 biological process negative regulation of metabolic process biological regulation primary metabolic process regulation of macromolecule metabolic process nucleobase-containing compound biosynthetic process gene expression macromolecule biosynthetic process nucleic acid metabolic process regulation of gene expression biosynthetic process negative regulation of biosynthetic process negative regulation of macromolecule biosynthetic process metabolic process cellular process regulation of macromolecule biosynthetic process macromolecule metabolic process regulation of DNA-templated transcription regulation of metabolic process negative regulation of RNA metabolic process developmental process multicellular organismal process regulation of multicellular organismal development regulation of developmental process blood vessel morphogenesis tube development angiogenesis vasculature development regulation of vasculature development circulatory system development anatomical structure morphogenesis multicellular organism development tube morphogenesis regulation of angiogenesis anatomical structure formation involved in morphogenesis anatomical structure development regulation of multicellular organismal process regulation of anatomical structure morphogenesis blood vessel development system development heart development animal organ development rhythmic process circadian rhythm epithelium development endothelial cell differentiation cellular developmental process endothelium development cell development tissue development epithelial cell differentiation cell morphogenesis endothelial cell development epithelial cell development endothelial cell morphogenesis epithelial cell morphogenesis cell differentiation cellular response to stimulus cellular response to BMP stimulus cell surface receptor protein serine/threonine kinase signaling pathway cellular response to growth factor stimulus cell surface receptor signaling pathway response to stimulus signaling response to endogenous stimulus cell communication cellular response to endogenous stimulus response to BMP transforming growth factor beta receptor superfamily signaling pathway signal transduction response to growth factor BMP signaling pathway enzyme-linked receptor protein signaling pathway protein destabilization regulation of protein stability regulation of biological quality respiratory tube development lung morphogenesis lung development respiratory system development animal organ morphogenesis negative regulation of programmed cell death regulation of apoptotic process regulation of programmed cell death cell death negative regulation of apoptotic process apoptotic process programmed cell death positive regulation of biological process positive regulation of macromolecule biosynthetic process positive regulation of metabolic process positive regulation of gene expression positive regulation of biosynthetic process positive regulation of macromolecule metabolic process positive regulation of cellular process regulation of osteoblast differentiation negative regulation of osteoblast differentiation negative regulation of developmental process regulation of cell differentiation osteoblast differentiation ossification negative regulation of cell differentiation response to chemical response to antibiotic regulation of signaling regulation of signal transduction regulation of MAPK cascade intracellular signal transduction regulation of intracellular signal transduction regulation of response to stimulus intracellular signaling cassette MAPK cascade regulation of cell communication cell population proliferation positive regulation of cell population proliferation positive regulation of epithelial cell proliferation regulation of cell population proliferation regulation of epithelial cell proliferation epithelial cell proliferation nervous system development generation of neurons neurogenesis neuron differentiation cell projection organization regulation of neurogenesis neuron projection development regulation of cell development cell projection morphogenesis neuron projection morphogenesis regulation of dendrite morphogenesis negative regulation of cellular component organization regulation of cell projection organization regulation of dendrite development negative regulation of multicellular organismal process regulation of neuron projection development regulation of cellular component organization plasma membrane bounded cell projection morphogenesis regulation of nervous system development cellular component organization negative regulation of neurogenesis dendrite development negative regulation of nervous system development cellular component organization or biogenesis negative regulation of cell projection organization plasma membrane bounded cell projection organization negative regulation of dendrite morphogenesis dendrite morphogenesis cell morphogenesis involved in neuron differentiation negative regulation of cell development neuron development regulation of plasma membrane bounded cell projection organization positive regulation of organelle organization regulation of cytoskeleton organization positive regulation of cellular component organization regulation of actin filament-based process regulation of actin filament bundle assembly cellular component biogenesis positive regulation of actin filament bundle assembly cellular component assembly actin filament bundle organization actin filament-based process regulation of actin filament organization actin cytoskeleton organization positive regulation of cellular component biogenesis positive regulation of cytoskeleton organization actin filament organization positive regulation of supramolecular fiber organization regulation of cellular component biogenesis regulation of organelle organization organelle organization regulation of actin cytoskeleton organization actin filament bundle assembly regulation of supramolecular fiber organization supramolecular fiber organization cytoskeleton organization collagen metabolic process regulation of epithelial cell differentiation negative regulation of epithelial cell differentiation regulation of endothelial cell differentiation negative regulation of endothelial cell differentiation negative regulation of gene expression transcription by RNA polymerase II regulation of transcription by RNA polymerase II negative regulation of transcription by RNA polymerase II negative regulation of cold-induced thermogenesis homeostatic process adaptive thermogenesis multicellular organismal-level homeostasis regulation of cold-induced thermogenesis cold-induced thermogenesis temperature homeostasis lung vasculature development	intracellular organelle centrosome microtubule organizing center cellular anatomical structure intracellular anatomical structure cytoskeleton organelle membraneless organelle intracellular membraneless organelle microtubule cytoskeleton cytoplasm membrane-bounded organelle nucleus membrane-enclosed lumen intracellular organelle centrosome microtubule organizing center cellular anatomical structure intracellular anatomical structure cytoskeleton organelle membraneless organelle intracellular membraneless organelle microtubule cytoskeleton cytoplasm membrane-bounded organelle nucleus membrane-enclosed lumen intracellular membrane-bounded organelle intracellular organelle lumen nucleoplasm organelle lumen nuclear lumen

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR026052	DNA-binding protein inhibitor	Family
A, B	IPR011598	Myc-type, basic helix-loop-helix (bHLH) domain	Domain
A, B	IPR036638	Helix-loop-helix DNA-binding domain superfamily	Homologous Superfamily

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.