TNNI2 Gene

Name	troponin I type 2 (skeletal, fast)
Description	This gene encodes a fast-twitch skeletal muscle protein, a member of the troponin I gene family, and a component of the troponin complex including troponin T, troponin C and troponin I subunits. The troponin complex, along with tropomyosin, is responsible for the calcium-dependent regulation of striated muscle contraction. Mouse studies show that this component is also present in vascular smooth muscle and may play a role in regulation of smooth muscle function. In addition to muscle tissues, this protein is found in corneal epithelium, cartilage where it is an inhibitor of angiogenesis to inhibit tumor growth and metastasis, and mammary gland where it functions as a co-activator of estrogen receptor-related receptor alpha. This protein also suppresses tumor growth in human ovarian carcinoma. Mutations in this gene cause myopathy and distal arthrogryposis type 2B. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Mar 2009]
Summary	{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nTNNI2 encodes fast skeletal muscle troponin I, a critical regulatory component of the troponin complex that modulates actomyosin contraction in fast‐twitch muscle fibers. Mutations in TNNI2 disrupt normal muscle contractile function and have been causally linked to a spectrum of distal arthrogryposis disorders—including distal arthrogryposis types 1, 2B, and even presentations overlapping with Freeman–Sheldon syndrome—by impairing the protein’s role in sarcomeric organization and force regulation."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "1", "end_ref": "6"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nBeyond its canonical role in muscle contraction, TNNI2 has been shown to localize to the nucleus where it functions as a transcriptional co‐activator. Specifically, fast skeletal troponin I can interact directly with estrogen receptor–related receptor alpha (ERRα) and enhance its transactivation, implying that TNNI2 may help regulate gene expression programs important for muscle metabolism and differentiation."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nMoreover, evidence indicates that TNNI2 is not exclusively expressed in skeletal muscle. Detection of fast troponin I transcripts and protein in vascular smooth muscle suggests a broader physiological role in modulating contractile properties of diverse muscle types. In addition, the measurement of circulating fast skeletal troponin I isoforms has emerged as a promising biomarker for muscle injury."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "8"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nFurthermore, therapeutic applications have been explored in which gene transfer of the fast‐twitch skeletal muscle troponin I (TnI‑fast) into ovarian carcinoma cells resulted in antiangiogenic effects and significant inhibition of tumor growth, illustrating TNNI2’s potential utility beyond muscle physiology."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "10"}]}, {"type": "t", "text": "\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Miao Jiang, Xiuli Zhao, Weitian Han, et al. "}, {"type": "b", "children": [{"type": "t", "text": "A novel deletion in TNNI2 causes distal arthrogryposis in a large Chinese family with marked variability of expression."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Hum Genet (2006)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1007/s00439-006-0183-4"}], "href": "https://doi.org/10.1007/s00439-006-0183-4"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "16802141"}], "href": "https://pubmed.ncbi.nlm.nih.gov/16802141"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Eva Kimber, Homa Tajsharghi, Anna-Karin Kroksmark, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Distal arthrogryposis: clinical and genetic findings."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Acta Paediatr (2012)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1111/j.1651-2227.2012.02708.x"}], "href": "https://doi.org/10.1111/j.1651-2227.2012.02708.x"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "22519952"}], "href": "https://pubmed.ncbi.nlm.nih.gov/22519952"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Bo Wang, Zhaojing Zheng, Zhigang Wang, et al. "}, {"type": "b", "children": [{"type": "t", "text": "A novel missense mutation of TNNI2 in a Chinese family cause distal arthrogryposis type 1."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Am J Med Genet A (2016)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/ajmg.a.37391"}], "href": "https://doi.org/10.1002/ajmg.a.37391"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "26374086"}], "href": "https://pubmed.ncbi.nlm.nih.gov/26374086"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "Xuefu Li, Miao Jiang, Weitian Han, et al. "}, {"type": "b", "children": [{"type": "t", "text": "A novel TNNI2 mutation causes Freeman-Sheldon syndrome in a Chinese family with an affected adult with only facial contractures."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Gene (2013)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.gene.2013.06.082"}], "href": "https://doi.org/10.1016/j.gene.2013.06.082"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "23850728"}], "href": "https://pubmed.ncbi.nlm.nih.gov/23850728"}]}, {"type": "r", "ref": 5, "children": [{"type": "t", "text": "Rie Seyama, Yuri Uchiyama, Yosuke Kaneshi, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Distal arthrogryposis in a girl arising from a novel TNNI2 variant inherited from paternal somatic mosaicism."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Hum Genet (2023)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1038/s10038-022-01117-x"}], "href": "https://doi.org/10.1038/s10038-022-01117-x"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "36631501"}], "href": "https://pubmed.ncbi.nlm.nih.gov/36631501"}]}, {"type": "r", "ref": 6, "children": [{"type": "t", "text": "Yue Li, Tianying Nong, Yiqiang Li, et al. "}, {"type": "b", "children": [{"type": "t", "text": "A TNNI2 variant c.525G>T causes distal arthrogryposis in a Chinese family."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Mol Genet Genomic Med (2022)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/mgg3.2042"}], "href": "https://doi.org/10.1002/mgg3.2042"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "36069346"}], "href": "https://pubmed.ncbi.nlm.nih.gov/36069346"}]}, {"type": "r", "ref": 7, "children": [{"type": "t", "text": "Yuping Li, Bin Chen, Jian Chen, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Fast skeletal muscle troponin I is a co-activator of estrogen receptor-related receptor alpha."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Biochem Biophys Res Commun (2008)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.bbrc.2008.02.147"}], "href": "https://doi.org/10.1016/j.bbrc.2008.02.147"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "18331830"}], "href": "https://pubmed.ncbi.nlm.nih.gov/18331830"}]}, {"type": "r", "ref": 8, "children": [{"type": "t", "text": "Carlos M Moran, Robert J Garriock, Melanie K Miller, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Expression of the fast twitch troponin complex, fTnT, fTnI and fTnC, in vascular smooth muscle."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cell Motil Cytoskeleton (2008)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/cm.20291"}], "href": "https://doi.org/10.1002/cm.20291"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "18548613"}], "href": "https://pubmed.ncbi.nlm.nih.gov/18548613"}]}, {"type": "r", "ref": 9, "children": [{"type": "t", "text": "Benjamin L Barthel, Dan Cox, Marissa Barbieri, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Elevation of fast but not slow troponin I in the circulation of patients with Becker and Duchenne muscular dystrophy."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Muscle Nerve (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/mus.27222"}], "href": "https://doi.org/10.1002/mus.27222"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "33683712"}], "href": "https://pubmed.ncbi.nlm.nih.gov/33683712"}]}, {"type": "r", "ref": 10, "children": [{"type": "t", "text": "GuangWu Xiong, Li Yang, YuQuan Wei, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Expression of the human fast-twitch skeletal muscle troponin I cDNA in a human ovarian carcinoma suppresses tumor growth."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Sci China C Life Sci (2007)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1007/s11427-007-2032-7"}], "href": "https://doi.org/10.1007/s11427-007-2032-7"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "17393089"}], "href": "https://pubmed.ncbi.nlm.nih.gov/17393089"}]}]}]}
Synonyms	FSTNI, AMCD2B, FSSV
Proteins	TNNI2_HUMAN
NCBI Gene ID	7136
API
Download Associations
Predicted Functions
Co-expressed Genes
Expression in Tissues and Cell Lines

Functional Associations

TNNI2 has 5,407 functional associations with biological entities spanning 9 categories (molecular profile, organism, chemical, disease, phenotype or trait, functional term, phrase or reference, structural feature, cell line, cell type or tissue, gene, protein or microRNA, sequence feature) extracted from 121 datasets.

Click the + buttons to view associations for TNNI2 from the datasets below.

If available, associations are ranked by standardized value

Harmonizome 3.0

TNNI2 Gene

Functional Associations

Please acknowledge the Harmonizome in your publications by citing the following reference(s):

	Dataset	Summary
	Allen Brain Atlas Adult Human Brain Tissue Gene Expression Profiles	tissues with high or low expression of TNNI2 gene relative to other tissues from the Allen Brain Atlas Adult Human Brain Tissue Gene Expression Profiles dataset.
	Allen Brain Atlas Adult Mouse Brain Tissue Gene Expression Profiles	tissues with high or low expression of TNNI2 gene relative to other tissues from the Allen Brain Atlas Adult Mouse Brain Tissue Gene Expression Profiles dataset.
	Allen Brain Atlas Aging Dementia and Traumatic Brain Injury Tissue Sample Gene Expression Profiles	tissue samples with high or low expression of TNNI2 gene relative to other tissue samples from the Allen Brain Atlas Aging Dementia and Traumatic Brain Injury Tissue Sample Gene Expression Profiles dataset.
	Allen Brain Atlas Developing Human Brain Tissue Gene Expression Profiles by Microarray	tissue samples with high or low expression of TNNI2 gene relative to other tissue samples from the Allen Brain Atlas Developing Human Brain Tissue Gene Expression Profiles by Microarray dataset.
	Allen Brain Atlas Prenatal Human Brain Tissue Gene Expression Profiles	tissues with high or low expression of TNNI2 gene relative to other tissues from the Allen Brain Atlas Prenatal Human Brain Tissue Gene Expression Profiles dataset.
	BioGPS Cell Line Gene Expression Profiles	cell lines with high or low expression of TNNI2 gene relative to other cell lines from the BioGPS Cell Line Gene Expression Profiles dataset.
	BioGPS Human Cell Type and Tissue Gene Expression Profiles	cell types and tissues with high or low expression of TNNI2 gene relative to other cell types and tissues from the BioGPS Human Cell Type and Tissue Gene Expression Profiles dataset.
	BioGPS Mouse Cell Type and Tissue Gene Expression Profiles	cell types and tissues with high or low expression of TNNI2 gene relative to other cell types and tissues from the BioGPS Mouse Cell Type and Tissue Gene Expression Profiles dataset.
	Carcinogenome Chemical Perturbation Carcinogenicity Signatures	small molecule perturbations changing expression of TNNI2 gene from the Carcinogenome Chemical Perturbation Carcinogenicity Signatures dataset.
	CCLE Cell Line Gene CNV Profiles	cell lines with high or low copy number of TNNI2 gene relative to other cell lines from the CCLE Cell Line Gene CNV Profiles dataset.
	CCLE Cell Line Gene Expression Profiles	cell lines with high or low expression of TNNI2 gene relative to other cell lines from the CCLE Cell Line Gene Expression Profiles dataset.
	CellMarker Gene-Cell Type Associations	cell types associated with TNNI2 gene from the CellMarker Gene-Cell Type Associations dataset.
	ChEA Transcription Factor Binding Site Profiles	transcription factor binding site profiles with transcription factor binding evidence at the promoter of TNNI2 gene from the CHEA Transcription Factor Binding Site Profiles dataset.
	ChEA Transcription Factor Targets	transcription factors binding the promoter of TNNI2 gene in low- or high-throughput transcription factor functional studies from the CHEA Transcription Factor Targets dataset.
	ChEA Transcription Factor Targets 2022	transcription factors binding the promoter of TNNI2 gene in low- or high-throughput transcription factor functional studies from the CHEA Transcription Factor Targets 2022 dataset.
	ClinVar Gene-Phenotype Associations 2025	phenotypes associated with TNNI2 gene from the curated ClinVar Gene-Phenotype Associations 2025 dataset.
	CM4AI KOLF21J CRISPRi Gene Perturbation Atlas	gene perturbations changing expression of TNNI2 gene from the CM4AI KOLF21J CRISPRi Gene Perturbation Atlas dataset.
	CMAP Signatures of Differentially Expressed Genes for Small Molecules	small molecule perturbations changing expression of TNNI2 gene from the CMAP Signatures of Differentially Expressed Genes for Small Molecules dataset.
	COMPARTMENTS Curated Protein Localization Evidence Scores	cellular components containing TNNI2 protein from the COMPARTMENTS Curated Protein Localization Evidence Scores dataset.
	COMPARTMENTS Curated Protein Localization Evidence Scores 2025	cellular components containing TNNI2 protein from the COMPARTMENTS Curated Protein Localization Evidence Scores 2025 dataset.
	COMPARTMENTS Text-mining Protein Localization Evidence Scores	cellular components co-occuring with TNNI2 protein in abstracts of biomedical publications from the COMPARTMENTS Text-mining Protein Localization Evidence Scores dataset.
	COMPARTMENTS Text-mining Protein Localization Evidence Scores 2025	cellular components co-occuring with TNNI2 protein in abstracts of biomedical publications from the COMPARTMENTS Text-mining Protein Localization Evidence Scores 2025 dataset.
	COSMIC Cell Line Gene Mutation Profiles	cell lines with TNNI2 gene mutations from the COSMIC Cell Line Gene Mutation Profiles dataset.
	CTD Gene-Chemical Interactions	chemicals interacting with TNNI2 gene/protein from the curated CTD Gene-Chemical Interactions dataset.
	CTD Gene-Disease Associations	diseases associated with TNNI2 gene/protein from the curated CTD Gene-Disease Associations dataset.
	DeepCoverMOA Drug Mechanisms of Action	small molecule perturbations with high or low expression of TNNI2 protein relative to other small molecule perturbations from the DeepCoverMOA Drug Mechanisms of Action dataset.
	DepMap CRISPR Gene Dependency	cell lines with fitness changed by TNNI2 gene knockdown relative to other cell lines from the DepMap CRISPR Gene Dependency dataset.
	DGIdb Drug Targets 2026	interacting drugs for TNNI2 protein from the DGIdb Drug Targets 2026 dataset.
	DISEASES Curated Gene-Disease Association Evidence Scores 2025	diseases involving TNNI2 gene from the DISEASES Curated Gene-Disease Association Evidence Scores 2025 dataset.
	DISEASES Experimental Gene-Disease Association Evidence Scores 2025	diseases associated with TNNI2 gene in GWAS datasets from the DISEASES Experimental Gene-Disease Assocation Evidence Scores 2025 dataset.
	DISEASES Text-mining Gene-Disease Association Evidence Scores	diseases co-occuring with TNNI2 gene in abstracts of biomedical publications from the DISEASES Text-mining Gene-Disease Assocation Evidence Scores dataset.
	DISEASES Text-mining Gene-Disease Association Evidence Scores 2025	diseases co-occuring with TNNI2 gene in abstracts of biomedical publications from the DISEASES Text-mining Gene-Disease Assocation Evidence Scores 2025 dataset.
	DisGeNET Gene-Disease Associations	diseases associated with TNNI2 gene in GWAS and other genetic association datasets from the DisGeNET Gene-Disease Associations dataset.
	DisGeNET Gene-Phenotype Associations	phenotypes associated with TNNI2 gene in GWAS and other genetic association datasets from the DisGeNET Gene-Phenoptype Associations dataset.
	ENCODE Histone Modification Site Profiles	histone modification site profiles with high histone modification abundance at TNNI2 gene from the ENCODE Histone Modification Site Profiles dataset.
	ENCODE Transcription Factor Binding Site Profiles	transcription factor binding site profiles with transcription factor binding evidence at the promoter of TNNI2 gene from the ENCODE Transcription Factor Binding Site Profiles dataset.
	ENCODE Transcription Factor Targets	transcription factors binding the promoter of TNNI2 gene in ChIP-seq datasets from the ENCODE Transcription Factor Targets dataset.
	ESCAPE Omics Signatures of Genes and Proteins for Stem Cells	PubMedIDs of publications reporting gene signatures containing TNNI2 from the ESCAPE Omics Signatures of Genes and Proteins for Stem Cells dataset.
	GAD High Level Gene-Disease Associations	diseases associated with TNNI2 gene in GWAS and other genetic association datasets from the GAD High Level Gene-Disease Associations dataset.
	GDSC Cell Line Gene Expression Profiles	cell lines with high or low expression of TNNI2 gene relative to other cell lines from the GDSC Cell Line Gene Expression Profiles dataset.