Overlapping and distinct signals through leptin receptor (OB-R) and a closely related cytokine signal transducer, gp130.
The structure of leptin receptor (OB-R) is highly homologous to that of gp130, the common signal transducing receptor component for the interleukin-6 family of cytokines. Based on this structural similarity, we examined signaling processes initiated by OB-R in comparison with those by gp130. Stimulation of either a long form of OB-R or gp130 led to tyrosine phosphorylation of STAT3, whereas stimulation of the truncated form of OB-R that is predominantly expressed in dbldb mice failed to do so. Stimulation of the long form OB-R did not induce tyrosine phosphorylation of a Src homology domain 2 containing protein tyrosine phosphatase, SHP-2, while stimulation of gp130 did. In contrast, activation of p42ERK2 is mediated by either the long form OB-R or gp130. Two closely related molecules, OB-R and gp130, thus appear to mediate overlapping but distinct signaling procedures.
Nakashima
K
K
Institute for Molecular and Cellular Biology, Osaka University, Japan.
Narazaki
M
M
Taga
T
T
D015703:Antigens, CD / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D050822:Cytokine Receptor gp130; D004789:Enzyme Activation; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D011956:Receptors, Cell Surface; D018121:Receptors, Cytokine / Q000378:metabolism*; D054411:Receptors, Leptin; D011994:Recombinant Proteins / Q000378:metabolism; D015398:Signal Transduction; D014443:Tyrosine / Q000378:metabolism
D015703:Antigens, CD; D002352:Carrier Proteins; C494199:IL6ST protein, human; C515448:LEPR protein, human; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D018121:Receptors, Cytokine; D054411:Receptors, Leptin; D011994:Recombinant Proteins; D050822:Cytokine Receptor gp130; D014443:Tyrosine; D011494:Protein Kinases