ETS1 - ETS proto-oncogene 1, transcription factor Gene

Also Known as p54; ETS-1; EWSR2; c-ets-1

Species: Homo sapiens

Gene Type: protein coding

Gene ID: 2113

About ETS1

Cytogenetic location: 11q24.3 Genomic coordinates (GRCh38): 11:128,458,765-128,587,558 (from NCBI)

This gene has 9 transcripts (splice variants), 211 orthologues, 28 paralogues and is associated with 1 phenotype. Broad expression in lymph node (RPKM 31.2), spleen (RPKM 21.4) and 22 other tissues.

Summary

This gene encodes a member of the ETS family of transcription factors, which are defined by the presence of a conserved ETS DNA-binding domain that recognizes the core consensus DNA sequence GGAA/T in target genes. These proteins function either as transcriptional activators or repressors of numerous genes, and are involved in stem cell development, cell senescence and death, and tumorigenesis. Alternatively spliced transcript variants encoding different isoforms have been described for this gene.[provided by RefSeq, Jul 2011]

ETS1 Products (4)

mRNA	Protein	Name
NM_001143820.2	NP_001137292.1	protein C-ets-1 isoform 1
NM_001162422.2	NP_001155894.1	protein C-ets-1 isoform 3
NM_001330451.2	NP_001317380.1	protein C-ets-1 isoform 4
NM_005238.4	NP_005229.1	protein C-ets-1 isoform 2

Gene Ontology

Molecular Function
Biological Process
Cellular Component

Molecular Function GO Annotation	Evidence	Verweise	Source
enables DNA-binding transcription activator activity, RNA polymerase II-specific	IDA IDA: Inferred from direct assay	15001984	GOA
enables DNA-binding transcription factor activity	IDA IDA: Inferred from direct assay	10698492	GOA
enables DNA-binding transcription factor activity, RNA polymerase II-specific	IDA IDA: Inferred from direct assay	21711453	GOA
enables RNA polymerase II cis-regulatory region sequence-specific DNA binding	IDA IDA: Inferred from direct assay	12119294	GOA
enables RNA polymerase II-specific DNA-binding transcription factor binding	IPI IPI: Inferred from physical interaction	11909962	GOA
enables identical protein binding	IPI IPI: Inferred from physical interaction	25609649	GOA
enables nuclear receptor coactivator activity	IMP IMP: Inferred from mutant phenotype	31146003	GOA
enables nucleic acid binding	EXP EXP: Inferred from Experiment	25083921	GOA
enables protein binding	IPI IPI: Inferred from physical interaction	10698492	GOA
enables transcription cis-regulatory region binding	IDA IDA: Inferred from direct assay	31146003	GOA
enables transcription corepressor binding	IDA IDA: Inferred from direct assay	10698492	GOA

Biological Process GO Annotation	Evidence	Verweise	Source
involved in PML body organization	IDA IDA: Inferred from direct assay	11909962	GOA
involved in cell motility	IMP IMP: Inferred from mutant phenotype	15247905	GOA
involved in negative regulation of cell cycle	IDA IDA: Inferred from direct assay	9266972	GOA
involved in negative regulation of cell cycle	IMP IMP: Inferred from mutant phenotype	7753825	GOA
involved in positive regulation of DNA-templated transcription	IDA IDA: Inferred from direct assay	10698492	GOA
involved in positive regulation of DNA-templated transcription	IMP IMP: Inferred from mutant phenotype	31146003	GOA
involved in positive regulation of angiogenesis	IMP IMP: Inferred from mutant phenotype	21081489	GOA
involved in positive regulation of blood vessel endothelial cell migration	IMP IMP: Inferred from mutant phenotype	21081489	GOA
involved in positive regulation of endothelial cell migration	IMP IMP: Inferred from mutant phenotype	15592518	GOA
involved in positive regulation of erythrocyte differentiation	IDA IDA: Inferred from direct assay	8620536	GOA
involved in positive regulation of gene expression	IMP IMP: Inferred from mutant phenotype	21081489	GOA
involved in positive regulation of inflammatory response	IDA IDA: Inferred from direct assay	21310411	GOA
involved in positive regulation of leukocyte adhesion to vascular endothelial cell	IMP IMP: Inferred from mutant phenotype	21310411	GOA
involved in positive regulation of miRNA transcription	IDA IDA: Inferred from direct assay	21711453	GOA
involved in positive regulation of transcription by RNA polymerase II	IDA IDA: Inferred from direct assay	11909962	GOA
involved in regulation of angiogenesis	IMP IMP: Inferred from mutant phenotype	15592518	GOA
involved in regulation of apoptotic process	IDA IDA: Inferred from direct assay	9266972	GOA
involved in response to antibiotic	IDA IDA: Inferred from direct assay	9266972	GOA
involved in transcription by RNA polymerase II	IDA IDA: Inferred from direct assay	7753825	GOA

Cellular Component GO Annotation	Evidence	Verweise	Source
located in nucleus	IDA IDA: Inferred from direct assay	11909962	GOA
located in nucleus	IMP IMP: Inferred from mutant phenotype	9266972	GOA

EXP: Inferred from Experiment IDA: Inferred from direct assay IPI: Inferred from physical interaction IMP: Inferred from mutant phenotype IGI: Inferred from genetic interaction IEP: Inferred from expression pattern

ETS1 Protein Structure

SAM_PNT

Ets

0
100
200
300
400
441 a.a.

Protein Preferred Names	Protein Names
protein C-ets-1	Avian erythroblastosis virus E26 (v-ets) oncogene homolog-1

ETS1 Protein-protein interaction Information

Type	Protein Name	Protein ID	Interactor	Interactor Species	Interactor ID	Detection Method	Verweise
Intra	ETS1	P14921	MEIS1	Homo sapiens	O00470	Anti Bait CoIP	18692240
Intra	ETS1	P14921	TAL1	Homo sapiens	P17542	Anti Bait CoIP	21179004
Intra	ETS1	P14921	CYBC1	Homo sapiens	Q9BQA9	Display Tech	20195357
Intra	ETS1	P14921	ARID4B	Homo sapiens	Q4LE39	Display Tech	20195357
Intra	ETS1	P14921	PRKDC	Homo sapiens	P78527	Anti Tag CoIP	21575865
Cross	ETS1	P14921	Gfi1	Mus musculus	P70338	Pull Down	17213822
Intra	ETS1	P14921	SP100	Homo sapiens	P23497	Y2H	15247905
Intra	ETS1	P14921	SP100	Homo sapiens	P23497	Anti Bait CoIP	15247905
Intra	ETS1	P14921	APLP2	Homo sapiens	Q06481	Display Tech	20195357
Intra	ETS1	P14921	JUN	Homo sapiens	P05412	Display Tech	20195357
Intra	ETS1	P14921	JUN	Homo sapiens	P05412	TAP	20195357
Intra	ETS1	P14921	NFKB1	Homo sapiens	P19838	PLA	25241761
Intra	ETS1	P14921	MAPK1	Homo sapiens	P28482	Anti Bait CoIP	22521293
Intra	ETS1	P14921	NFKB1	Homo sapiens	P19838	Affinity Chrom	35140242
Intra	ETS1	P14921	SMARCA2	Homo sapiens	P51531	BioID	35140242
Intra	ETS1	P14921	SMARCA2	Homo sapiens	P51531	Display Tech	20195357
Intra	ETS1	P14921	MAPK1	Homo sapiens	P28482	PLA	22521293

Cross: Cross-species interaction Intra: Intraspecies interaction

Recombinant ETS1 Proteins

Art. -Nr.	Produktname	Accession	Reinheit
HY-P70292	ETS1/EWSR2 Protein, Human (His)	P14921-5 (M1-T272)	≥ 95%, as determined by reducing SDS-PAGE.

ETS1 Antibodies

Art. -Nr.	Produktname	Anwendung	Reactivity
HY-P82749	ETS1 Antibody (YA2494)	WB	Human, Mouse
HY-P82749A	ETS1 Antibody (YA2494)(PBS only)	WB	Human, Mouse
HY-P84103	ETS1 Antibody (YA3800)	WB, IHC-P, ICC/IF, FC, ELISA	Human
HY-P84103A	ETS1 Antibody (YA3800)(PBS only)	WB, IHC-P, ICC/IF, FC, ELISA	Human

Related Diseases

Diseases	Alias
Jacobsen Syndrome	Chromosome 11q Deletion Syndrome Partial 11q Monosomy Syndrome Jacobsen Distal 11q Deletion Syndrome JBS 11q Partial Monosomy Syndrome Chromosome 11q Deletion 11q Deletion 11q Monosomy Deletion 11q Monosomy 11q Partial Monosomy 11q 11q Deletion Disorder 11q Deletion Syndrome 11q Terminal Deletion Disorder 11q- Deletion Syndrome 11q23 Deletion Disorder Jacobsen Thrombocytopenia 11q Terminal Deletion Syndrome Del(11)(Q23.3) Del(11)(Qter) Distal Deletion 11q Distal Monosomy 11q Monosomy 11qter Telomeric Deletion 11q Paris-Trousseau Thrombocytopenia
Systemic Lupus Erythematosus	Lupus Nephritis SLE Disseminated Lupus Erythematosus Systemic Lupus Erythematosus, Susceptibility To Lupus Erythematosus, Systemic Lupus Nephritis, Susceptibility To Libman-Sacks Disease Systemic Lupus Erythematosus Susceptibility To Sle - Lupus Erythematosus, Systemic Le Syndrome Lupus Lupus Erythematosus Systemic Lupus Erythematosus, Systemic, Susceptibility To Lupus Vulgaris Lupus Erythematosus, Discoid Lupus Erythematosus Systemic Lupus Erythematosus Nos Sle - [Systemic Lupus Erythematosus]
Benign Meningioma	Meningioma, Benign
Endometrial Cancer	Endometrial Carcinoma Endometrial Neoplasm Malignant Neoplasm Of Endometrium Endometrioid Carcinoma Endometrial Neoplasms Carcinoma, Endometrioid Endometrial Cancer, Familial Endometrial Carcinoma, Somatic Endometrial Cancer, Susceptibility To Endometrial Ca Malignant Endometrial Neoplasm Neoplasm Of Endometrium Primary Malignant Neoplasm Of Endometrium Tumor Of Endometrium Carcinoma Of The Endometrium Endometrioid Carcinoma Of Female Reproductive System ENDMC Carcinoma Endometrioid Endometrial Cancers Cancer, Endometrial Uterine Corpus Cancer
Ovarian Cancer	Ovarian Carcinoma Ovarian Neoplasm Malignant Tumour Of Ovary Cancer Of The Ovary Epithelial Ovarian Cancer Neoplasm Of Ovary Ovarian Neoplasms Ovarian Cancers Malignant Neoplasm Of Ovary Primary Malignant Neoplasm Of Ovary Ovarian Cancer, Somatic Malignant Ovarian Tumor Ovary Neoplasm Primary Ovarian Cancer Tumor Of The Ovary Malignant Neoplasm Of The Ovary Malignant Tumor Of The Ovary Ovarian Malignant Tumor OC Ovarian Carcinomas Cancer, Ovarian Cancer Of Ovary Ovary Cancer Ca Ovary
Ataxia-Telangiectasia	Ataxia Telangiectasia Louis-Bar Syndrome AT At1 Ataxia-Telangiectasia Syndrome Ataxia - Telangiectasia Variant Boder-Sedgwick Syndrome Louis Bar Syndrome Cerebello-Oculocutaneous Telangiectasia Immunodeficiency With Ataxia Telangiectasia A-T Ataxia Telangiectasia Syndrome Atm Telangiectasia, Cerebello-Oculocutaneous Ataxia-Telangiectasia Variant
Nasopharyngeal Carcinoma	Malignant Neoplasm Of Nasopharynx Npc Nasopharyngeal Cancer Nasopharyngeal Carcinoma 1 Nasopharynx Carcinoma Nasopharyngeal Neoplasms Npca Carcinoma Of Nasopharynx Malignant Nasopharyngeal Tumor Nasopharynx Cancer Squamous Cell Carcinoma Of The Nasopharynx Nasopharyngeal Neoplasm Cancer Of Nasopharynx
Colorectal Cancer	Colon Cancer Colorectal Carcinoma Colon Carcinoma Colorectal Cancer, Susceptibility To Carcinoma Of Colon CRC Colorectal Cancer With Chromosomal Instability, Somatic Colon Cancer, Somatic Colon Cancer, Susceptibility To Colonic Neoplasms Colorectal Neoplasms Colorectal Cancer, Somatic Colon Cancer, Advanced, Somatic Colonic Carcinoma Colorectal Carcinomas Colon Cancers Colorectal Cancers Cancer, Colorectal, Somatic Cancer, Colon Cancer, Colorectal, Susceptibility To Colorectal Neoplasm Colonic Neoplasm Malignant Tumor Of Colon
Melanoma	Malignant Melanoma Cutaneous Melanoma Naevocarcinoma Malignant Melanomas
Tetralogy Of Fallot	TOF Fallot Tetralogy Ventricular Septal Defect With Pulmonary Stenosis Or Atresia, Dextraposition Of Aorta, And Hypertrophy Of Right Ventricle Tetrad Of Fallot Fallot Tetrad Fallot Disease Fallot Complex Subpulmonic Stenosis, Ventricular Septal Defect, Overriding Aorta, And Right Ventricular Hypertrophy Interventricular Septal Defect With Dextroposition Of Aorta, Pulmonary Stenosis And Hypertrophy Of Right Ventricle Interventricular Septal Defect, In Tetralogy Of Fallot Ventricular Septal Defect With Obstructed Right Ventricular Outflow Tof - [Tetralogy Of Fallot] Pulmonary Atresia With Ventricular Septal Defect [Fallot Type] Pulmonary Atresia, Ventricular Septal Defect And Mapcas Pulmonary Atresia With Ventricular Septal Defect And Systemic-To-Pulmonary Collateral Arteries [Fallot Type]
Ewing Sarcoma	Neuroepithelioma Ewing'S Tumor Primitive Neuroectodermal Tumor Ewings Sarcoma Ewing'S Sarcoma Peripheral Neuroepithelioma ES Ewings Sarcoma-Primitive Neuroectodermal Tumor Localized Peripheral Primitive Neuroectodermal Tumor Peripheral Primitive Neuroectodermal Tumor Ewing Tumor Sarcoma, Ewing'S Ewing Family Of Tumors Extraosseous Ewing Tumor Askin Tumor Ewing'S Family Localized Tumor Ewing'S Sarcoma/Peripheral Primitive Neuroectodermal Tumor Localized Ewing Sarcoma Localized Ewing'S Sarcoma Localized Ewing'S Sarcoma/Peripheral Primitive Neuroectodermal Tumor Localized Ewing'S Tumor Pnet Of Thoracopulmonary Region Tumor Of The Ewing Family Skeletal Ewing Sarcoma Osseous Ewing Sarcoma Ppnet Peripheral Pnet Extraskeletal Ewing Sarcoma Eoe Extraosseous Ewing Sarcoma Extraskeletal Ewing Tumor Esft Ewing Sarcoma Family Of Tumors Pne Pnet Pnet Of The Chest Wall Sarcoma, Ewing Neuroectodermal Tumors, Primitive, Peripheral Neuroectodermal Tumor, Primitive Disorder Of Eye Askin'S Tumor Extraosseous Ewings Sarcoma-Primitive Neuroepithelial Tumor Neuroepithelioma, Peripheral
Granulomatosis With Polyangiitis	GPA Wegener Granulomatosis Wegener Granulomatosis, Formerly Midline Granulomatosis Wg, Formerly Necrotizing Respiratory Granulomatosis Wg Wegeners Granulomatosis Pauci-Immune Glomerulonephritis Associated With Granulomatosis With Polyangiitis
Burkitt Lymphoma	Burkitt'S Lymphoma BL Burkitt Lymphoma, Somatic Burkitt Lymphoma/Leukaemia Burkitt'S Tumor Burkitt'S Tumor Or Lymphoma Malignant Lymphoma, Burkitt'S Type Small Non-Cleaved Cell Lymphoma, Burkitt'S Type Small Non-Cleaved Cell Lymphoma Burkitt Tumor Burkitts Lymphoma Lymphoma, Small Noncleaved-Cell Burkitt Tumour Diffuse Small Noncleaved Malignant Burkitt Lymphoma Malignant Burkitt Lymphoma “Burkitt-Like” Lymphoma Undifferentiated Burkitt Lymphoma Small Noncleaved Cell Burkitt Lymphoma
Breast Cancer	Breast Carcinoma Male Breast Cancer Breast Cancer, Familial Malignant Neoplasm Of Breast Breast Cancer, Susceptibility To Breast Cancer, Early-Onset Malignant Tumor Of Breast Carcinoma Of Male Breast Breast Cancer, Invasive Ductal Breast Cancer, Protection Against Breast Cancer, Somatic Breast Cancer, Male Breast Cancer, Lobular, Somatic Breast Tumor Mammary Cancer Mammary Tumor Malignant Neoplasm Of Male Breast Mammary Carcinoma Male Breast Carcinoma Familial Cancer Of Breast Invasive Ductal Breast Carcinoma Breast Cancer Susceptibility Breast Cancer, Male, Susceptibility To Breast Cancer, Early-Onset, Susceptibility To Malignant Tumor Of The Breast Mammary Neoplasm Primary Breast Cancer Neoplasm Of Male Breast Carcinoma Of Breast Breast Cancer In Men Familial Breast Cancer Cancer Of Breast BC Breast Cancer Familial Breast Cancer Familial Male Breast Cancer, Familial Male Breast Male Carcinoma Breast Neoplasms Breast Neoplasms, Male Mammary Tumors Mammary Carcinomas Cancer, Breast Cancer, Breast, Susceptibility Invasive Breast Ductal Carcinoma Breast Neoplasm Susceptibility To Breast Cancer Mammary Neoplasms Animal Mammary Neoplasms Primary Malignant Neoplasm Of Breast Infiltrating Ductal Carcinoma Of Breast Infiltrating Duct Carcinoma Of Unspecified Site Infiltrating Ductular Carcinoma Of Unspecified Site Invasive Breast Carcinoma Of No Special Type Microinvasive Carcinoma Of Breast Carcinoma With Apocrine Differentiation
T-Cell Acute Lymphoblastic Leukemia	T-Cell Leukemia Acute T Cell Leukemia Precursor T Lymphoblastic Leukemia Precursor T-Lymphoblastic Lymphoma/Leukemia T Acute Lymphoblastic Leukemia T-Cell Acute Lymphocytic Leukaemia T-Cell Lymphoblastic Leukemia/Lymphoma Leukemia T-Cell Leukemia, T-Cell Leukemia, Acute, Lymphoblastic, T-Cell Leukemia, T-Cell Acute Lymphoblastic Leukemia, Acute T-Cell Precursor T-Cell Lymphoblastic Leukemia-Lymphoma Precursor T-Cell Lymphoblastic Lymphoma Precursor T Cell Lymphoblastic Leukemia/Lymphoblastic Lymphoma
Gastric Cancer	Stomach Cancer Gastric Carcinoma Stomach Carcinoma Gastric Cancer, Somatic Gastric Neoplasm Carcinoma Of Stomach Stomach Neoplasms Malignant Neoplasm Of Stomach Gastric Cancer Risk After H. Pylori Infection Cancer Of The Stomach Adult Stomach Cancer Adult Stomach Carcinoma GASC Gastric Cancer Intestinal Gastric Cancers Gastric Carcinomas Cancer, Gastric Stomach Neoplasm Malignant Neoplasm Of Body Of Stomach Malignant Tumor Of Lesser Curve Of Stomach Gastrocarcinoma Of Unspecified Site Leather Bottle Stomach Carcinoma Of Fundus Of Stomach Cancer Of Fundus Of Stomach Primary Malignant Neoplasm Of Body Of Stomach Cancer Of Body Of Stomach Primary Malignant Neoplasm Of Pyloric Antrum Pyloric Antrum Cancer Malignant Tumour Of Stomach
Prostate Cancer	Prostate Carcinoma Prostate Cancer, Familial Prostate Neoplasm Prostate Cancer, Somatic Prostate Cancer, Susceptibility To Prostatic Cancer Prostatic Neoplasms Hereditary Prostate Cancer Prostatic Neoplasm Cancer Of Prostate Carcinoma Of Prostate Familial Prostate Cancer Familial Prostate Carcinoma Malignant Tumor Of Prostate Malignant Neoplasm Of Prostate Prostate Cancer, Familial, Susceptibility To Malignant Tumor Of The Prostate Ngp - New Growth Of Prostate Tumor Of The Prostate Prostate Cancer, Hereditary Cancer Of The Prostate Malignant Neoplasm Of The Prostate Prostatic Carcinoma PC Prca Cancer, Prostate Malignant Prostatic Tumour Malignant Tumour Of Prostate Primary Prostate Cancer Primary Malignant Neoplasm Of Prostate Prostate Gland Cancer
Hepatocellular Carcinoma	Liver Cancer Primary Liver Cancer HCC Hepatoma Malignant Neoplasm Of Liver Liver Neoplasms Cancer, Hepatocellular Liver Cell Carcinoma Lcc Hepatoblastoma, Somatic Hepatic Cancer Primary Malignant Neoplasm Of Liver Rare Tumor Of Liver And Intrahepatic Biliary Tract Hepatocellular Carcinoma, Somatic Hepatocellular Carcinoma, Childhood Type, Somatic Hepatocellular Cancer, Somatic Ca Liver - Primary Hepatic Neoplasm Malignant Hepato-Biliary Neoplasm Malignant Neoplasm Of Liver, Not Specified As Primary Or Secondary Malignant Neoplasm Of Liver, Primary Malignant Tumor Of Liver Neoplasm Of Liver Non-Resectable Primary Hepatic Malignant Neoplasm Resectable Malignant Neoplasm Of Liver Resectable Malignant Neoplasm Of The Liver Primary Liver Carcinoma Primary Malignant Liver Neoplasm Primary Cancer Of Liver Primary Tumor Of The Liver Rare Tumor Of Liver And Ibt Hepatocellular Cancer Neoplasm Of The Liver Carcinoma, Hepatocellular Hepatomas Liver Neoplasm Liver Carcinoma Liver And Intrahepatic Biliary Tract Carcinoma Malignant Hepatobiliary Neoplasm Adult Primary Hepatocellular Carcinoma Hepatoblastoma Carcinoma Of Liver Malignant Liver Tumour Malignant Hepatic Tumour
Breast Rhabdomyosarcoma	Rhabdomyosarcoma Of The Breast
Meningioma, Familial	Meningioma Familial Meningioma Meningioma, Familial, Susceptibility To Meningeal Neoplasm Meningeal Neoplasms Meningiomas Meningioma, Nf2-Related, Somatic Meningioma, Sis-Related Meningothelial Cell Tumor Neoplasm Of The Meninges Primary Meningeal Tumor Familial Multiple Meningioma MNGMA Meningioma, Benign, No Icd-O Subtype Intracranial Meningioma Meningothelial Cell Neoplasm Supratentorial Meningioma Primary Neoplasm Of Spinal Meninges Benign Intracranial Meningioma Benign Meningioma Meningeal Tumours Meningeal Sarcoma Of Unspecified Site Meningothelial Sarcoma Of Unspecified Site

Diseases	Alias
Waldenstroem'S Macroglobulinemia	Waldenstroem'S Macroglobulinemia Waldenstroem'S Macroglobulinemia Macroglobulinemia Of Waldenstrom Lymphoplasmacytic Lymphoma With Igm Gammopathy Lymphoplasmacytic Lymphoma Waldenstroem'S Macroglobulinemia Waldenstroem'S Macroglobulinemia Macroglobulinemia Of Waldenstrom Lymphoplasmacytic Lymphoma With Igm Gammopathy Lymphoplasmacytic Lymphoma

Related Agents

Pre-clinical Phase

Pre-clinical Phase

Bioactive Molecules (5)

Art. -Nr.	Produktname	Wirkung	Reinheit	Rare Diseases
HY-W002199	6:2 Fluorotelomer alcohol		99.96%	Unkown
HY-RS04562	ETS1 Human Pre-designed siRNA Set A	Pre-designed Set	/	Unkown
HY-RS16879	Ets1 Mouse Pre-designed siRNA Set A	Pre-designed Set	/	Unkown
HY-RS23321	Ets1 Rat Pre-designed siRNA Set A	Pre-designed Set	/	Unkown
HY-RS28129	Kcnh8 Rat Pre-designed siRNA Set A	Pre-designed Set	/	Unkown

Orthologs Information

Species	Symbol	Source	ID
Bos taurus	ETS1	VGNC	VGNC:28626
Mus musculus	ETS1	MGD	MGI:95455
Canis familiaris	ETS1	VGNC	VGNC:40494
Macaca mulatta	ETS1	VGNC	VGNC:72439
Rattus norvegicus	ETS1	RGD	RGD:2583
Felis catus	ETS1	VGNC	VGNC:61980
Others	ETS1	NCBI