IL2 signaling (WP49)

Homo sapiens

IL-2 is a multifunctional cytokine with pleiotropic effects on several cells of the immune system. IL-2 was originally discovered as a T cell growth factor, but it was also found to have actions related to B cell proliferation, and cytolytic activity of natural killer cells. IL-2 also activates lymphokine activated killer cells. In contrast to its proliferative effects, IL-2 also has potent activity in a process known as activation-induced cell death. More recently, IL-2 was shown to promote tolerance through its effects on regulatory T cell development. IL-2 clinically has anti-cancer effects as well as utility in supporting T cell numbers in HIV/AIDS. There are three classes of IL-2 receptors, binding IL-2 with low, intermediate, or high-affinity. The low affinity receptor (IL-2Rα alone) is not functional; signaling by IL-2 involves either the high affinity hetero-trimeric receptor containing IL-2Rα, IL-2Rβ and the common cytokine receptor gamma chain (originally named IL-2Rγ and now generally denoted as γc) or the intermediate affinity heterodimeric receptor composed of IL-2Rβ and γc. IL-2 stimulation induces the activation of the Janus family tyrosine kinases JAK1 and JAK3, which associate with IL-2Rβ and γc, respectively. These kinases in turn phosphorylate IL-2Rβ and induce tyrosine phosphorylation of STATs (signal transducers and activators of transcription) and various other downstream targets. The downstream signaling pathways activated by IL-2 also involves mitogen-activated protein kinase and phosphoinositide 3-kinase signaling modules, leading to both mitogenic and anti-apoptotic signals. Please access this pathway at [ NetSlim] database. NetPath is a collaborative project between PandeyLab at Johns Hopkins University ( and the Institute of Bioinformatics ( If you use this pathway, please cite the NetPath website until the pathway is published.


Akhilesh Pandey , Kristina Hanspers , Martina Summer-Kutmon , Martijn Van Iersel , Alex Pico , NetPath , Christine Chichester , Friederike Ehrhart , Egon Willighagen , and Eric Weitz


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Homo sapiens



Pathway Ontology

interleukin-2 signaling pathway Interleukin mediated signaling pathway


Label Type Compact URI Comment
IL2RA GeneProduct ensembl:ENSG00000134460
HRAS GeneProduct ensembl:ENSG00000174775
STAT5B Protein ncbigene:6777
STAT3 Protein ncbigene:6774
STAT1 Protein ncbigene:6772
MAPK1 Protein ncbigene:5594
STAT1 Protein ncbigene:6772
AKT1 Protein ncbigene:207
CBL Protein ncbigene:867
GAB2 Protein ncbigene:9846
MAP2K2 Protein ncbigene:5605
SHC1 Protein ncbigene:6464
FYN Protein ncbigene:2534
IL2 Protein ncbigene:3558
CRKL Protein ncbigene:1399
LCK Protein ncbigene:3932
STAT5B Protein ncbigene:6777
IL2RG Protein ncbigene:3561
RPS6 Protein ncbigene:6194
IL2RA Protein ensembl:ENSG00000134460
STAT1 Protein ncbigene:6772
MTOR Protein ncbigene:4137
SOS1 Protein ncbigene:6654
RAF1 Protein ncbigene:5894
MAP2K1 Protein ncbigene:5604
IL2RB Protein ncbigene:3560
STAT3 Protein ncbigene:6774
STAT1 Protein ncbigene:6772
CISH Protein ncbigene:1154
FOXO3A Protein ncbigene:2309
STAT1 Protein ncbigene:6772
GRB2 Protein ncbigene:2885
JAK3 Protein ncbigene:3718
MAPK3 Protein ncbigene:5595
STAT3 Protein ncbigene:6774
PTK2B Protein ncbigene:2185
PTPN11 Protein ncbigene:5781
RPS6KB1 Protein ncbigene:6198
RPS6KB2 Protein ncbigene:6199
JAK1 Protein ncbigene:3716
STAT5A Protein ncbigene:6776
SYK Protein ncbigene:6850
STAT5A Protein ncbigene:6776
STAT5A Protein ncbigene:6776
NMI Protein ncbigene:9111
SOCS3 Protein ncbigene:9021
PIK3R1 Protein ncbigene:5295
STAT3 Protein ncbigene:6774
STAT3 Protein ncbigene:6774


  1. NetPath: a public resource of curated signal transduction pathways. Kandasamy K, Mohan SS, Raju R, Keerthikumar S, Kumar GSS, Venugopal AK, et al. Genome Biol. 2010 Jan 12;11(1):R3. PubMed Europe PMC Scholia