1TWN - JenaLib

Asym./Biol. Unit - manually (Jmol Viewer)

Asym./Biol. Unit (Jmol Viewer)

Asym./Biol. Unit - sites (Jmol Viewer)

Title :   CRYSTAL STRUCTURES OF FERROUS AND FERROUS-NO FORMS OF VERDOHEME IN A COMPLEX WITH HUMAN HEME OXYGENASE-1: CATALYTIC IMPLICATIONS FOR HEME CLEAVAGE

Authors :   L. Lad, P. R. Ortiz De Montellano, T. L. Poulos

Date :   01 Jul 04 (Deposition) - 05 Jul 05 (Release) - 24 Feb 09 (Revision)

Method :   X-RAY DIFFRACTION

Resolution :   2.20

Chains :   Asym./Biol. Unit : A,B

Keywords :   Heme Oxygenase-1, Heme Degredation, Oxidoreductase (Keyword Search: [Gene Ontology, PubMed, Web (Google)] )

Reference :   L. Lad, P. R. Ortiz De Montellano, T. L. Poulos
Crystal Structures Of Ferrous And Ferrous-No Forms Of Verdoheme In A Complex With Human Heme Oxygenase-1: Catalytic Implications For Heme Cleavage.
J. Inorg. Biochem. V. 98 1686 2004
PubMed-ID: 15522396 | Reference-DOI: 10.1016/J.JINORGBIO.2004.07.004
(for further references see the PDB file header)

Molecule 1 - HEME OXYGENASE 1
	Chains	:	A, B
	EC Number	:	1.14.99.3
	Engineered	:	YES
	Expression System	:	ESCHERICHIA COLI
	Expression System Plasmid	:	PCWORI
	Expression System Strain	:	DH5ALPHA
	Expression System Taxid	:	562
	Expression System Vector Type	:	PLASMID
	Gene	:	HMOX1, HO1, HO
	Organism Common	:	HUMAN
	Organism Scientific	:	HOMO SAPIENS
	Organism Taxid	:	9606
	Synonym	:	HO-1

		1	2
Asymmetric/Biological Unit	:	A	B

Summary Information (see also Sequences/Alignments below)

Asymmetric/Biological Unit (1, 2)

No.	Name	Count	Type	Full Name
1	VER	2	Ligand/Ion	IRON-OCTAETHYLPORPHYRIN

Asymmetric Unit (2, 2)

No.	Name	Evidence	Residues	Description
1	AC1	SOFTWARE	LYS A:18 , HIS A:25 , ALA A:28 , GLN A:38 , TYR A:134 , THR A:135 , GLY A:139 , SER A:142 , GLY A:143 , LEU A:147 , ARG A:183 , PHE A:207 , ASN A:210	BINDING SITE FOR RESIDUE VER A 300
2	AC2	SOFTWARE	LYS B:18 , HIS B:25 , TYR B:134 , THR B:135 , ARG B:136 , GLY B:139 , SER B:142 , ARG B:183 , PHE B:207 , ASN B:210 , HOH B:355	BINDING SITE FOR RESIDUE VER B 300

(no "SS Bond" information available for 1TWN)

(no "Cis Peptide Bond" information available for 1TWN)

Asymmetric/Biological Unit (1, 2)

								dbSNP	PDB
No.	Source	Variant ID	Variant			UniProt ID	Status	ID	Chain	Variant
1	UniProt	VAR_022156	P	106	L	HMOX1_HUMAN	Polymorphism	9282702	A/B	P	106	L

SNP/SAP Summary Statistics (UniProtKB/Swiss-Prot)

Asymmetric/Biological Unit (1, 2)

	PROSITE			UniProtKB		PDB
No.	ID	AC	Description	ID	Location	Count	Location
1	HEME_OXYGENASE	PS00593	Heme oxygenase signature.	HMOX1_HUMAN	129-139	2	A:129-139 B:129-139

Asymmetric/Biological Unit (3, 6)

	ENSEMBL					UniProtKB			PDB
No.	Transcript ID	Exon	Exon ID	Genome Location	Length	ID	Location	Length	Count	Location	Length
1.2a	ENST00000216117	2a	ENSE00001915869	chr22:35776828-35777189	362	HMOX1_HUMAN	1-8	8	0	-	-
1.3	ENST00000216117	3	ENSE00000880006	chr22:35779099-35779219	121	HMOX1_HUMAN	8-48	41	2	A:10-48 B:10-48	39 39
1.4c	ENST00000216117	4c	ENSE00000653517	chr22:35782678-35783169	492	HMOX1_HUMAN	49-212	164	2	A:49-212 B:49-212	164 164
1.5a	ENST00000216117	5a	ENSE00000653518	chr22:35785857-35785956	100	HMOX1_HUMAN	213-246	34	2	A:213-223 B:213-223	11 11
1.6	ENST00000216117	6	ENSE00001380117	chr22:35789461-35790207	747	HMOX1_HUMAN	246-288	43	0	-	-

Asymmetric/Biological Unit

Reformat:	Number of residues per line = ('0' or empty: single-line sequence representation)
	Number of residues per labelling interval =
	UniProt sequence: complete aligned part

Show mapping:	SCOP domains	CATH domains	Pfam domains	Secondary structure (by author)
	SAPs(SNPs)	PROSITE motifs	Exons
	(details for a mapped element are shown in a popup box when the mouse pointer rests over it)

Chain A from PDB  Type:PROTEIN  Length:214
 aligned with HMOX1_HUMAN | P09601 from UniProtKB/Swiss-Prot  Length:288

    Alignment length:214
                                    19        29        39        49        59        69        79        89        99       109       119       129       139       149       159       169       179       189       199       209       219    
          HMOX1_HUMAN    10 PQDLSEALKEATKEVHTQAENAEFMRNFQKGQVTRDGFKLVMASLYHIYVALEEEIERNKESPVFAPVYFPEELHRKAALEQDLAFWYGPRWQEVIPYTPAMQRYVKRLHEVGRTEPELLVAHAYTRYLGDLSGGQVLKKIAQKALDLPSSGEGLAFFTFPNIASATKFKQLYRSRMNSLEMTPAVRQRVIEEAKTAFLLNIQLFEELQELLTH 223
               SCOP domains d1twna_ A: Heme oxygenase-1 (HO-1)                                                                                                                                                                                     SCOP domains
               CATH domains 1twnA00 A:10-223 Heme Oxygenase; Chain A                                                                                                                                                                               CATH domains
               Pfam domains ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author ..hhhhhhhhhhhhhhhhhhhhhhhhhhhh...hhhhhhhhhhhhhhhhhhhhhhhhhh.....hhhhhhhhhhhhhhhhhhhhhhhhh.hhhhhh..hhhhhhhhhhhhhhhhhh..hhhhhhhhhhhhhh.hhhhhhhhhhhhhh.......hhhhh.....hhhhhhhhhhhhhhh...hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh. Sec.struct. author
                 SAPs(SNPs) ------------------------------------------------------------------------------------------------L--------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE -----------------------------------------------------------------------------------------------------------------------HEME_OXYGEN------------------------------------------------------------------------------------ PROSITE
               Transcript 1 Exon 1.3  PDB: A:10-48 UniProt: 8-48   Exon 1.4c  PDB: A:49-212 UniProt: 49-212                                                                                                                            Exon 1.5a   Transcript 1
                 1twn A  10 PQDLSEALKEATKEVHTQAENAEFMRNFQKGQVTRDGFKLVMASLYHIYVALEEEIERNKESPVFAPVYFPEELHRKAALEQDLAFWYGPRWQEVIPYTPAMQRYVKRLHEVGRTEPELLVAHAYTRYLGDLSGGQVLKKIAQKALDLPSSGEGLAFFTFPNIASATKFKQLYRSRMNSLEMTPAVRQRVIEEAKTAFLLNIQLFEELQELLTH 223
                                    19        29        39        49        59        69        79        89        99       109       119       129       139       149       159       169       179       189       199       209       219

Chain B from PDB  Type:PROTEIN  Length:214
 aligned with HMOX1_HUMAN | P09601 from UniProtKB/Swiss-Prot  Length:288

    Alignment length:214
                                    19        29        39        49        59        69        79        89        99       109       119       129       139       149       159       169       179       189       199       209       219    
          HMOX1_HUMAN    10 PQDLSEALKEATKEVHTQAENAEFMRNFQKGQVTRDGFKLVMASLYHIYVALEEEIERNKESPVFAPVYFPEELHRKAALEQDLAFWYGPRWQEVIPYTPAMQRYVKRLHEVGRTEPELLVAHAYTRYLGDLSGGQVLKKIAQKALDLPSSGEGLAFFTFPNIASATKFKQLYRSRMNSLEMTPAVRQRVIEEAKTAFLLNIQLFEELQELLTH 223
               SCOP domains d1twnb_ B: Heme oxygenase-1 (HO-1)                                                                                                                                                                                     SCOP domains
               CATH domains 1twnB00 B:10-223 Heme Oxygenase; Chain A                                                                                                                                                                               CATH domains
           Pfam domains (1) -Heme_oxygenase-1twnB01 B:11-216                                                                                                                                                                               ------- Pfam domains (1)
           Pfam domains (2) -Heme_oxygenase-1twnB02 B:11-216                                                                                                                                                                               ------- Pfam domains (2)
         Sec.struct. author ..hhhhhhhhhhhhhhhhhhhhhhhhhhhh...hhhhhhhhhhhhhhhhhhhhhhhhhhh....hhhhhhhhhhhhhhhhhhhhhhhhh.hhhhh...hhhhhhhhhhhhhhhhhh..hhhhhhhhhhhhhhhhhhhhhhhhhhhhh.......hhhhh.....hhhhhhhhhhhhhhh...hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh Sec.struct. author
                 SAPs(SNPs) ------------------------------------------------------------------------------------------------L--------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE -----------------------------------------------------------------------------------------------------------------------HEME_OXYGEN------------------------------------------------------------------------------------ PROSITE
               Transcript 1 Exon 1.3  PDB: B:10-48 UniProt: 8-48   Exon 1.4c  PDB: B:49-212 UniProt: 49-212                                                                                                                            Exon 1.5a   Transcript 1
                 1twn B  10 PQDLSEALKEATKEVHTQAENAEFMRNFQKGQVTRDGFKLVMASLYHIYVALEEEIERNKESPVFAPVYFPEELHRKAALEQDLAFWYGPRWQEVIPYTPAMQRYVKRLHEVGRTEPELLVAHAYTRYLGDLSGGQVLKKIAQKALDLPSSGEGLAFFTFPNIASATKFKQLYRSRMNSLEMTPAVRQRVIEEAKTAFLLNIQLFEELQELLTH 223
                                    19        29        39        49        59        69        79        89        99       109       119       129       139       149       159       169       179       189       199       209       219

Legend:		→ Mismatch	(orange background)
	-	→ Gap	(green background, '-', border residues have a numbering label)
		→ Modified Residue	(blue background, lower-case, 'x' indicates undefined single-letter code, labelled with number + name)
	x	→ Chemical Group	(purple background, 'x', labelled with number + name, e.g. ACE or NH2)
	extra numbering lines below/above indicate numbering irregularities and modified residue names etc., number ends below/above '\|'

Asymmetric/Biological Unit

Classes(

)

Folds(

)

Superfamilies( (-)

)

Families(

)

Protein Domains( (-)

)

Organisms( (-)

)

Class: All alpha proteins (14657)

Fold: Heme oxygenase-like (107)

Superfamily: Heme oxygenase-like (107)

Family: Eukaryotic type heme oxygenase (69)

Protein domain: Heme oxygenase-1 (HO-1) (49)

Human (Homo sapiens) [TaxId: 9606] (23)

1a	d1twna_	A:
1b	d1twnb_	B:

Asymmetric/Biological Unit

Classes(

)

Architectures( (-)

)

Topologies( (-)

)

Homologous Superfamilies( (-)

)

Organisms( (-)

)

Class: Mainly Alpha (13335)

Architecture: Up-down Bundle (3216)

Topology: Heme Oxygenase; Chain A (84)

Homologous Superfamily: Heme Oxygenase; Chain A (84)

Human (Homo sapiens) (25)

1a	1twnA00	A:10-223
1b	1twnB00	B:10-223

Asymmetric/Biological Unit

Clans(

)

Families(

)

Organisms( (-)

)

Clan: HO (49)

Family: Heme_oxygenase (37)

Homo sapiens (Human) (21)

1a	Heme_oxygenase-1twnB01	B:11-216
1b	Heme_oxygenase-1twnB02	B:11-216

Asymmetric/Biological Unit(hide GO term definitions)

Chain A,B (HMOX1_HUMAN | P09601)

molecular function
	GO:0019899	enzyme binding	Interacting selectively and non-covalently with any enzyme.
	GO:0020037	heme binding	Interacting selectively and non-covalently with heme, any compound of iron complexed in a porphyrin (tetrapyrrole) ring.
	GO:0004392	heme oxygenase (decyclizing) activity	Catalysis of the reaction: heme + 3 donor-H2 + 3 O2 = biliverdin + Fe2+ + CO + 3 acceptor + 3 H2O.
	GO:0046872	metal ion binding	Interacting selectively and non-covalently with any metal ion.
	GO:0016491	oxidoreductase activity	Catalysis of an oxidation-reduction (redox) reaction, a reversible chemical reaction in which the oxidation state of an atom or atoms within a molecule is altered. One substrate acts as a hydrogen or electron donor and becomes oxidized, while the other acts as hydrogen or electron acceptor and becomes reduced.
	GO:0004630	phospholipase D activity	Catalysis of the reaction: a phosphatidylcholine + H2O = choline + a phosphatidate.
	GO:0005515	protein binding	Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).
	GO:0042803	protein homodimerization activity	Interacting selectively and non-covalently with an identical protein to form a homodimer.
	GO:0004871	signal transducer activity	Conveys a signal across a cell to trigger a change in cell function or state. A signal is a physical entity or change in state that is used to transfer information in order to trigger a response.
biological process
	GO:0001525	angiogenesis	Blood vessel formation when new vessels emerge from the proliferation of pre-existing blood vessels.
	GO:0006915	apoptotic process	A programmed cell death process which begins when a cell receives an internal (e.g. DNA damage) or external signal (e.g. an extracellular death ligand), and proceeds through a series of biochemical events (signaling pathway phase) which trigger an execution phase. The execution phase is the last step of an apoptotic process, and is typically characterized by rounding-up of the cell, retraction of pseudopodes, reduction of cellular volume (pyknosis), chromatin condensation, nuclear fragmentation (karyorrhexis), plasma membrane blebbing and fragmentation of the cell into apoptotic bodies. When the execution phase is completed, the cell has died.
	GO:0008219	cell death	Any biological process that results in permanent cessation of all vital functions of a cell. A cell should be considered dead when any one of the following molecular or morphological criteria is met: (1) the cell has lost the integrity of its plasma membrane; (2) the cell, including its nucleus, has undergone complete fragmentation into discrete bodies (frequently referred to as apoptotic bodies). The cell corpse (or its fragments) may be engulfed by an adjacent cell in vivo, but engulfment of whole cells should not be considered a strict criteria to define cell death as, under some circumstances, live engulfed cells can be released from phagosomes (see PMID:18045538).
	GO:0006879	cellular iron ion homeostasis	Any process involved in the maintenance of an internal steady state of iron ions at the level of a cell.
	GO:0071243	cellular response to arsenic-containing substance	Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of an arsenic stimulus from compounds containing arsenic, including arsenates, arsenites, and arsenides.
	GO:0071276	cellular response to cadmium ion	Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a cadmium (Cd) ion stimulus.
	GO:0034605	cellular response to heat	Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a heat stimulus, a temperature stimulus above the optimal temperature for that organism.
	GO:0071456	cellular response to hypoxia	Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a stimulus indicating lowered oxygen tension. Hypoxia, defined as a decline in O2 levels below normoxic levels of 20.8 - 20.95%, results in metabolic adaptation at both the cellular and organismal level.
	GO:0031670	cellular response to nutrient	Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a nutrient stimulus.
	GO:0001935	endothelial cell proliferation	The multiplication or reproduction of endothelial cells, resulting in the expansion of a cell population. Endothelial cells are thin flattened cells which line the inside surfaces of body cavities, blood vessels, and lymph vessels, making up the endothelium.
	GO:0034101	erythrocyte homeostasis	Any process of regulating the production and elimination of erythrocytes within an organism.
	GO:0007588	excretion	The elimination by an organism of the waste products that arise as a result of metabolic activity. These products include water, carbon dioxide (CO2), and nitrogenous compounds.
	GO:0042167	heme catabolic process	The chemical reactions and pathways resulting in the breakdown of heme, any compound of iron complexed in a porphyrin (tetrapyrrole) ring.
	GO:0042168	heme metabolic process	The chemical reactions and pathways involving heme, any compound of iron complexed in a porphyrin (tetrapyrrole) ring.
	GO:0006788	heme oxidation	The chemical reactions and pathways resulting in the loss of electrons from one or more atoms in heme.
	GO:0035556	intracellular signal transduction	The process in which a signal is passed on to downstream components within the cell, which become activated themselves to further propagate the signal and finally trigger a change in the function or state of the cell.
	GO:0008630	intrinsic apoptotic signaling pathway in response to DNA damage	A series of molecular signals in which an intracellular signal is conveyed to trigger the apoptotic death of a cell. The pathway is induced by the detection of DNA damage, and ends when the execution phase of apoptosis is triggered.
	GO:0055072	iron ion homeostasis	Any process involved in the maintenance of an internal steady state of iron ions within an organism or cell.
	GO:0034383	low-density lipoprotein particle clearance	The process in which a low-density lipoprotein particle is removed from the blood via receptor-mediated endocytosis and its constituent parts degraded.
	GO:0043392	negative regulation of DNA binding	Any process that stops or reduces the frequency, rate or extent of DNA binding. DNA binding is any process in which a gene product interacts selectively with DNA (deoxyribonucleic acid).
	GO:0008285	negative regulation of cell proliferation	Any process that stops, prevents or reduces the rate or extent of cell proliferation.
	GO:1902042	negative regulation of extrinsic apoptotic signaling pathway via death domain receptors	Any process that stops, prevents or reduces the frequency, rate or extent of extrinsic apoptotic signaling pathway via death domain receptors.
	GO:0002686	negative regulation of leukocyte migration	Any process that stops, prevents, or reduces the frequency, rate, or extent of leukocyte migration.
	GO:0032764	negative regulation of mast cell cytokine production	Any process that stops, prevents, or reduces the frequency, rate, or extent of mast cell cytokine production.
	GO:0043305	negative regulation of mast cell degranulation	Any process that stops, prevents, or reduces the rate of mast cell degranulation.
	GO:0010656	negative regulation of muscle cell apoptotic process	Any process that decreases the rate or frequency of muscle cell apoptotic process, a form of programmed cell death induced by external or internal signals that trigger the activity of proteolytic caspases whose actions dismantle a muscle cell and result in its death.
	GO:0043524	negative regulation of neuron apoptotic process	Any process that stops, prevents, or reduces the frequency, rate or extent of cell death by apoptotic process in neurons.
	GO:0043433	negative regulation of sequence-specific DNA binding transcription factor activity	Any process that stops, prevents, or reduces the frequency, rate or extent of the activity of a transcription factor, any factor involved in the initiation or regulation of transcription.
	GO:0048662	negative regulation of smooth muscle cell proliferation	Any process that stops, prevents or reduces the rate or extent of smooth muscle cell proliferation.
	GO:0055114	oxidation-reduction process	A metabolic process that results in the removal or addition of one or more electrons to or from a substance, with or without the concomitant removal or addition of a proton or protons.
	GO:0043123	positive regulation of I-kappaB kinase/NF-kappaB signaling	Any process that activates or increases the frequency, rate or extent of I-kappaB kinase/NF-kappaB signaling.
	GO:0045766	positive regulation of angiogenesis	Any process that activates or increases angiogenesis.
	GO:0045080	positive regulation of chemokine biosynthetic process	Any process that activates or increases the frequency, rate or extent of the chemical reactions and pathways resulting in the formation of chemokines.
	GO:0048661	positive regulation of smooth muscle cell proliferation	Any process that activates or increases the rate or extent of smooth muscle cell proliferation.
	GO:0051260	protein homooligomerization	The process of creating protein oligomers, compounds composed of a small number, usually between three and ten, of identical component monomers. Oligomers may be formed by the polymerization of a number of monomers or the depolymerization of a large protein polymer.
	GO:0045765	regulation of angiogenesis	Any process that modulates the frequency, rate or extent of angiogenesis.
	GO:0008217	regulation of blood pressure	Any process that modulates the force with which blood travels through the circulatory system. The process is controlled by a balance of processes that increase pressure and decrease pressure.
	GO:0051090	regulation of sequence-specific DNA binding transcription factor activity	Any process that modulates the frequency, rate or extent of the activity of a transcription factor, any factor involved in the initiation or regulation of transcription.
	GO:0034395	regulation of transcription from RNA polymerase II promoter in response to iron	Any process that modulates the frequency, rate or extent of transcription from an RNA polymerase II promoter in response to an iron stimulus.
	GO:0043619	regulation of transcription from RNA polymerase II promoter in response to oxidative stress	Modulation of the frequency, rate or extent of transcription from an RNA polymerase II promoter as a result of a stimulus indicating the organism is under oxidative stress, a state often resulting from exposure to high levels of reactive oxygen species, e.g. superoxide anions, hydrogen peroxide (H2O2), and hydroxyl radicals.
	GO:0043627	response to estrogen	Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of stimulus by an estrogen, C18 steroid hormones that can stimulate the development of female sexual characteristics.
	GO:0042542	response to hydrogen peroxide	Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a hydrogen peroxide (H2O2) stimulus.
	GO:0001666	response to hypoxia	Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a stimulus indicating lowered oxygen tension. Hypoxia, defined as a decline in O2 levels below normoxic levels of 20.8 - 20.95%, results in metabolic adaptation at both the cellular and organismal level.
	GO:0035094	response to nicotine	Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a nicotine stimulus.
	GO:0006979	response to oxidative stress	Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of oxidative stress, a state often resulting from exposure to high levels of reactive oxygen species, e.g. superoxide anions, hydrogen peroxide (H2O2), and hydroxyl radicals.
	GO:0007264	small GTPase mediated signal transduction	Any series of molecular signals in which a small monomeric GTPase relays one or more of the signals.
	GO:0014806	smooth muscle hyperplasia	A process, occurring in smooth muscle, in which there is an increase in cell number by cell division, often leading to an increase in the size of an organ.
	GO:0002246	wound healing involved in inflammatory response	The series of events that restore integrity to damaged tissue that contribute to an inflammatory response.
cellular component
	GO:0005901	caveola	A membrane raft that forms small pit, depression, or invagination that communicates with the outside of a cell and extends inward, indenting the cytoplasm and the cell membrane. Examples include flask-shaped invaginations of the plasma membrane in adipocytes associated with caveolin proteins, and minute pits or incuppings of the cell membrane formed during pinocytosis. Caveolae may be pinched off to form free vesicles within the cytoplasm.
	GO:0005829	cytosol	The part of the cytoplasm that does not contain organelles but which does contain other particulate matter, such as protein complexes.
	GO:0005783	endoplasmic reticulum	The irregular network of unit membranes, visible only by electron microscopy, that occurs in the cytoplasm of many eukaryotic cells. The membranes form a complex meshwork of tubular channels, which are often expanded into slitlike cavities called cisternae. The ER takes two forms, rough (or granular), with ribosomes adhering to the outer surface, and smooth (with no ribosomes attached).
	GO:0005789	endoplasmic reticulum membrane	The lipid bilayer surrounding the endoplasmic reticulum.
	GO:0005615	extracellular space	That part of a multicellular organism outside the cells proper, usually taken to be outside the plasma membranes, and occupied by fluid.
	GO:0043231	intracellular membrane-bounded organelle	Organized structure of distinctive morphology and function, bounded by a single or double lipid bilayer membrane and occurring within the cell. Includes the nucleus, mitochondria, plastids, vacuoles, and vesicles. Excludes the plasma membrane.
	GO:0016020	membrane	A lipid bilayer along with all the proteins and protein complexes embedded in it an attached to it.
	GO:0005730	nucleolus	A small, dense body one or more of which are present in the nucleus of eukaryotic cells. It is rich in RNA and protein, is not bounded by a limiting membrane, and is not seen during mitosis. Its prime function is the transcription of the nucleolar DNA into 45S ribosomal-precursor RNA, the processing of this RNA into 5.8S, 18S, and 28S components of ribosomal RNA, and the association of these components with 5S RNA and proteins synthesized outside the nucleolus. This association results in the formation of ribonucleoprotein precursors; these pass into the cytoplasm and mature into the 40S and 60S subunits of the ribosome.
	GO:0005634	nucleus	A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.
	GO:0048471	perinuclear region of cytoplasm	Cytoplasm situated near, or occurring around, the nucleus.

Asymmetric/Biological Unit
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	1twn
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Access by UniProt ID/Accession number
	HMOX1_HUMAN \| P09601
		Protein Disorder Prediction	:	DisEMBL \| FoldIndex \| GLOBPLOT (for more information see DisProt)

Description

Compounds

Structural Features

Chains, Units

Ligands, Modified Residues, Ions (1, 2)

Sites (2, 2)

SS Bonds (0, 0)

Cis Peptide Bonds (0, 0)

Sequence-Structure Mapping

SAPs(SNPs)/Variants (1, 2)

PROSITE Motifs (1, 2)

Exons (3, 6)

Sequences/Alignments

Classification and Annotation

SCOP Domains (1, 2)

CATH Domains (1, 2)

Pfam Domains (1, 2)

Gene Ontology (67, 67)

Visualization

Interactive Views

Still Images

Databases and Analysis Tools

Databases

Analysis Tools

Related Entries

Entries Sharing at Least One Protein Chain (UniProt ID)

Related Entries Specified in the PDB File