A novel protein MAJN binds to Jak3 and inhibits apoptosis induced by IL-2 deprival.
To find a possible signal interacting with the Jak3 N-terminal, we screened the human peripheral blood cDNA library through both a two-hybrid system and a tyrosine-phosphorylation-modified two-hybrid system using the N-terminal of Jak3 as bait. Results showed that one new homologue of myosin heavy chain, designated MAJN (molecule associated with Jak3 N-terminal), could bind to Jak3 in a tyrosine-phosphorylation-independent manner. The interaction between Jak3 and MAJN was further confirmed by immunoprecipitation in BAF-B03 beta cells. To investigate the function of MAJN, we have constructed the BAF-B03 beta/MAJN cell line that stably expresses MAJN and found that overexpression of MAJN can partially inhibit the apoptosis induced by interleukin-2 deprival. Further studies are needed to elucidate how MAJN executes its function to antagonize BAF-B03beta cell death in the absence of IL-2.
Ji
H
H
Shanghai Institute of Biochemistry, Chinese Academy of Sciences (CAS), Shanghai, China.
Zhai
Q
Q
Zhu
J
J
Yan
M
M
Sun
L
L
Liu
X
X
Zheng
Z
Z
D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins; D001665:Binding Sites; D002352:Carrier Proteins; D006801:Humans; D007376:Interleukin-2 / Q000172:deficiency*; D053616:Janus Kinase 3; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins; D011233:Precipitin Tests; D011485:Protein Binding; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D017384:Sequence Deletion; D020798:Two-Hybrid System Techniques; D009218:Myosins
D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins; D007376:Interleukin-2; D053616:Janus Kinase 3; D018995:Myosin Heavy Chains; D009687:Nuclear Proteins; D011505:Protein-Tyrosine Kinases; C407152:MYO18A protein, human; D009218:Myosins; C507933:JAK3 protein, human