Reactome: A Curated Pathway Database
THIS SITE IS USED FOR CURATION AND TESTING
IT IS NOT STABLE, IS LINKED TO AN INCOMPLETE DATA SET, AND IS NOT MONITORED FOR PERFORMANCE. WE STRONGLY RECOMMEND THE USE OF OUR PUBLIC SITE

Query author contributions in Reactome

Reactome depends on collaboration between our curation team and outside experts to assemble and peer-review its pathway modules. The integration of ORCID within Reactome enables us to meet a key challenge with authoring, curating and reviewing biological information by incentivizing and crediting the external experts that contribute their expertise and time to the Reactome curation process. More information is available at ORCID and Reactome.

If you have an ORCID ID that is not listed on this page, please forward this information to us and we will update your Reactome pathway records.

Name Email address

Details on Person UniProt:P07948 LYN

Class:IdReferenceGeneProduct:58853
_chainChangeLoginitiator methionine:1 added on Fri February 6 2015;chain:2-512 added on Fri February 6 2015;initiator methionine:1 for 58853 removed on Fri Nov 03 2023;initiator methionine: for 58853 added on Fri Nov 03 2023;initiator methionine: for 58853 removed on Fri Aug 15 2025;initiator methionine:1 for 58853 added on Fri Aug 15 2025
_displayNameUniProt:P07948 LYN
_timestamp2025-08-15 22:09:25
chaininitiator methionine:1
chain:2-512
checksum408D3D461204E378
commentFUNCTION Non-receptor tyrosine-protein kinase that transmits signals from cell surface receptors and plays an important role in the regulation of innate and adaptive immune responses, hematopoiesis, responses to growth factors and cytokines, integrin signaling, but also responses to DNA damage and genotoxic agents. Functions primarily as negative regulator, but can also function as activator, depending on the context. Required for the initiation of the B-cell response, but also for its down-regulation and termination. Plays an important role in the regulation of B-cell differentiation, proliferation, survival and apoptosis, and is important for immune self-tolerance. Acts downstream of several immune receptors, including the B-cell receptor, CD79A, CD79B, CD5, CD19, CD22, FCER1, FCGR2, FCGR1A, TLR2 and TLR4. Plays a role in the inflammatory response to bacterial lipopolysaccharide. Mediates the responses to cytokines and growth factors in hematopoietic progenitors, platelets, erythrocytes, and in mature myeloid cells, such as dendritic cells, neutrophils and eosinophils. Acts downstream of EPOR, KIT, MPL, the chemokine receptor CXCR4, as well as the receptors for IL3, IL5 and CSF2. Plays an important role in integrin signaling. Regulates cell proliferation, survival, differentiation, migration, adhesion, degranulation, and cytokine release. Involved in the regulation of endothelial activation, neutrophil adhesion and transendothelial migration (PubMed:36932076). Down-regulates signaling pathways by phosphorylation of immunoreceptor tyrosine-based inhibitory motifs (ITIM), that then serve as binding sites for phosphatases, such as PTPN6/SHP-1, PTPN11/SHP-2 and INPP5D/SHIP-1, that modulate signaling by dephosphorylation of kinases and their substrates. Phosphorylates LIME1 in response to CD22 activation. Phosphorylates BTK, CBL, CD5, CD19, CD72, CD79A, CD79B, CSF2RB, DOK1, HCLS1, LILRB3/PIR-B, MS4A2/FCER1B, SYK and TEC. Promotes phosphorylation of SIRPA, PTPN6/SHP-1, PTPN11/SHP-2 and INPP5D/SHIP-1. Mediates phosphorylation of the BCR-ABL fusion protein. Required for rapid phosphorylation of FER in response to FCER1 activation. Mediates KIT phosphorylation. Acts as an effector of EPOR (erythropoietin receptor) in controlling KIT expression and may play a role in erythroid differentiation during the switch between proliferation and maturation. Depending on the context, activates or inhibits several signaling cascades. Regulates phosphatidylinositol 3-kinase activity and AKT1 activation. Regulates activation of the MAP kinase signaling cascade, including activation of MAP2K1/MEK1, MAPK1/ERK2, MAPK3/ERK1, MAPK8/JNK1 and MAPK9/JNK2. Mediates activation of STAT5A and/or STAT5B. Phosphorylates LPXN on 'Tyr-72'. Kinase activity facilitates TLR4-TLR6 heterodimerization and signal initiation. Phosphorylates SCIMP on 'Tyr-107'; this enhances binding of SCIMP to TLR4, promoting the phosphorylation of TLR4, and a selective cytokine response to lipopolysaccharide in macrophages (By similarity). Phosphorylates CLNK (By similarity). Phosphorylates BCAR1/CAS and NEDD9/HEF1 (PubMed:9020138).CATALYTIC ACTIVITY L-tyrosyl-[protein] + ATP = O-phospho-L-tyrosyl-[protein] + ADP + H(+)ACTIVITY REGULATION Subject to autoinhibition, mediated by intramolecular interactions between the SH2 domain and the C-terminal phosphotyrosine. Phosphorylation at Tyr-397 is required for optimal activity. Phosphorylated by CSK at Tyr-508; phosphorylation at Tyr-508 inhibits kinase activity. Kinase activity is modulated by dephosphorylation by PTPRC/CD45. Inhibited by Dasatinib, PP2, and SU6656.SUBUNIT Interacts with TEC. Interacts (via SH2 domain) with FLT3 (tyrosine phosphorylated). Interacts with LIME1 and with CD79A upon activation of the B-cell antigen receptor. Interacts with the B-cell receptor complex. Interacts with phosphorylated THEMIS2. Interacts with EPOR. Interacts with MS4A2/FCER1B. Interaction (via the SH2 and SH3 domains) with MUC1 is stimulated by IL7 and the subsequent phosphorylation increases the binding between MUC1 and CTNNB1/beta-catenin. Interacts with ADAM15. Interacts with NDFIP2 and more weakly with NDFIP1. Interacts with FASLG. Interacts with KIT. Interacts with HCLS1. Interacts with FCGR2B. Interacts with FCGR1A; the interaction may be indirect. Interacts with CD19, CD22, CD79A and CD79B. Interacts (via SH3 domain) with CBLC, PPP1R15A and PDE4A. Interacts with TGFB1I1. Interacts (via SH3 domain) with PIK3R1, the regulatory subunit of phosphatidylinositol 3-kinase; this interaction enhances phosphatidylinositol 3-kinase activity. Interacts with CSF2RB, the common subunit of the IL3, IL5 and CSF2 receptors. Interacts with PAG1; identified in a complex with PAG1 and STAT3. Interacts with ABL1. Interacts with PTPN6/SHP-1. Interacts (via SH3 domain) with SCIMP (via proline-rich region) (PubMed:21930792). This interaction facilitates the phosphorylation of SCIMP on 'Tyr-107', which enhances binding of SCIMP to TLR4, and consequently the phosphorylation of TLR4 in response to stimulation by lipopolysaccharide in macrophages (By similarity). Interacts with LPXN (via LD motif 3) and the interaction is induced upon B-cell antigen receptor (BCR) activation. Interacts (via SH3-domain) with ANKRD54 (via ankyrin repeat region) in an activation-independent status of LYN. Forms a multiprotein complex with ANKRD54 and HCLS1. Interacts (via SH2 and SH3 domains) with UNC119; leading to LYN activation. Interacts with CD36. Interacts with LYN (By similarity). Interacts with SKAP1 and FYB1; this interaction promotes the phosphorylation of CLNK (By similarity). Interacts with BCAR1/CAS and NEDD9/HEF1 (PubMed:9020138).SUBUNIT (Microbial infection) Interacts with Epstein-Barr virus LMP2A.SUBUNIT (Microbial infection) Interacts with Herpes virus saimiri tyrosine kinase interacting protein (Tip).INTERACTION Accumulates in the nucleus by inhibition of CRM1-mediated nuclear export. Nuclear accumulation is increased by inhibition of its kinase activity. The trafficking from the Golgi apparatus to the plasma membrane occurs in a kinase domain-dependent but kinase activity independent manner and is mediated by exocytic vesicular transport. Detected on plasma membrane lipid rafts.ALTERNATIVE PRODUCTS Detected in monocytes (at protein level). Detected in placenta, and in fetal brain, lung, liver and kidney. Widely expressed in a variety of organs, tissues, and cell types such as epidermoid, hematopoietic, and neuronal cells. Expressed in primary neuroblastoma tumors.DOMAIN The protein kinase domain plays an important role in its localization in the cell membrane.PTM Ubiquitinated by CBL, leading to its degradation. Ubiquitination is SH3-dependent.PTM Autophosphorylated (PubMed:18056483, PubMed:18070987, PubMed:7935444, PubMed:9171348, PubMed:9341198). Phosphorylated on tyrosine residues in response to KIT signaling (PubMed:9341198). Phosphorylation at Tyr-397 is required for optimal activity (PubMed:16920712). Phosphorylation at Tyr-508 inhibits kinase activity (PubMed:9171348). Phosphorylated at Tyr-508 by CSK (PubMed:7935444). Dephosphorylated by PTPRC/CD45 (By similarity). Becomes rapidly phosphorylated upon activation of the B-cell receptor and the immunoglobulin receptor FCGR1A (PubMed:8064233). Phosphorylated in response to ITGB1 in B-cells (PubMed:9020138).DISEASE The disease is caused by variants affecting the gene represented in this entry.DISEASE Constitutively phosphorylated and activated in cells from a number of chronic myelogenous leukemia (CML) and acute myeloid leukemia (AML) patients. Mediates phosphorylation of the BCR-ABL fusion protein. Abnormally elevated expression levels or activation of LYN signaling may play a role in survival and proliferation of some types of cancer cells.SIMILARITY Belongs to the protein kinase superfamily. Tyr protein kinase family. SRC subfamily.
descriptionrecommendedName: Tyrosine-protein kinase Lyn ecNumber: 2.7.10.2 alternativeName: Lck/Yes-related novel protein tyrosine kinase alternativeName: V-yes-1 Yamaguchi sarcoma viral related oncogene homolog alternativeName: p53Lyn alternativeName: p56Lyn
geneNameLYN
JTK8
identifierP07948
isSequenceChangedFALSE
keyword3D-structure
Adaptive immunity
Alternative splicing
ATP-binding
Cell membrane
Cytoplasm
Disease variant
Golgi apparatus
Host-virus interaction
Immunity
Inflammatory response
Innate immunity
Kinase
Lipoprotein
Membrane
Myristate
Nucleotide-binding
Nucleus
Palmitate
Phosphoprotein
Proteomics identification
Proto-oncogene
Reference proteome
SH2 domain
SH3 domain
Transferase
Tyrosine-protein kinase
Ubl conjugation
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9909836] Weiser, Joel, 2024-05-14
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
[InstanceEdit:9963647] Weiser, Joel, 2025-08-15
nameLYN
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8989051] ENSEMBL:ENSG00000254087 LYN [Homo sapiens]
secondaryIdentifierLYN_HUMAN
A0AVQ5
sequenceLength512
species[Species:48887] Homo sapiens
(isoformParent)[ReferenceIsoform:149956] UniProt:P07948-2 LYN [Homo sapiens]
[ReferenceIsoform:402560] UniProt:P07948-1 LYN [Homo sapiens]
(referenceEntity)[EntityWithAccessionedSequence:197943] LYN [plasma membrane] [Homo sapiens]
[EntityWithAccessionedSequence:354251] LYN [cytosol] [Homo sapiens]
[EntityWithAccessionedSequence:2454229] p-Y397-LYN [plasma membrane] [Homo sapiens]
[EntityWithAccessionedSequence:8942608] p-Y397-LYN [cytosol] [Homo sapiens]
[EntityWithAccessionedSequence:9606875] MyrG2-PalmC3-LYN [plasma membrane] [Homo sapiens]
[EntityWithAccessionedSequence:9705728] MyrG2-PalmC3-LYN [endocytic vesicle membrane] [Homo sapiens]
[EntityWithAccessionedSequence:9707903] MyrG2-PalmC3-LYN [lysosomal membrane] [Homo sapiens]
(referenceSequence)[ModifiedResidue:2454241] O4'-phospho-L-tyrosine at 397
[ModifiedResidue:8942603] O4'-phospho-L-tyrosine at 397
[ModifiedResidue:9606872] N-myristoylglycine at 2
[ModifiedResidue:9606877] S-palmitoyl-L-cysteine at 3
[Change default viewing format]
No pathways have been reviewed or authored by UniProt:P07948 LYN (58853)