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Leptin Receptor Signal Transduction: OBRa and OBRb offaType

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Abstract

We report herein the characterization of activities of signal transduction for three types of leptin receptors (OBRs) from rats, the OBRa, OBRb, and OBRb withfamutation (OBRb-fa), by measurement of the levels of tyrosine phosphorylation of STAT3 (signal transducers and activators of transcription 3) and MAPK (mitogen-activated protein kinase), which are induced by leptin stimulation of CHO cells stably expressing the OBR (CHO-OBRb, CHO-OBRa, or CHO-OBRb-facells). As the result of leptin stimulation, enhanced levels of tyrosine phosphorylation of STAT3 and MAPK were detected in CHO-OBRb cells. In CHO-OBRb-facells, enhancement levels for both were lower than those in CHO-OBRb cells. In CHO-OBRa cells, only the phosphorylation of MAPK was detected. These data suggest that these reduced signaling activities cause obesity infa/farats and that OBRa, which has been generally thought to be inactive at signaling, actually transmits signals through the MAPK pathway.

References (39)

  • H. Chen et al.

    Cell

    (1996)
  • M. Iida et al.

    Biochem. Biophys. Res. Commun.

    (1996)
  • T. Murakami et al.

    Biochem. Biophys. Res. Commun.

    (1997)
  • D.W. White et al.

    J. Biol. Chem.

    (1997)
  • Y. Wang et al.

    J. Biol. Chem.

    (1997)
  • Y. Takahashi et al.

    J. Biol. Chem.

    (1997)
  • C.S. Hill et al.

    Cell

    (1995)
  • M. Boshart et al.

    Gene

    (1992)
  • C.-H. Heldin

    Cell

    (1995)
  • K. Nakashima et al.

    FEBS Lett.

    (1997)
  • T. Kishimoto et al.

    Cell

    (1994)
  • Y.-D. Wang et al.

    J. Biol. Chem.

    (1995)
  • C. Bjørbæk et al.

    J. Biol. Chem.

    (1997)
  • C.J. Marshall

    Cell

    (1995)
  • B.D. Bennett et al.

    Curr. Biol.

    (1996)
  • Y. Zhang et al.

    Nature

    (1994)
  • A.M. Ingalls et al.

    J. Hered.

    (1950)
  • M.A. Pelleymounter et al.

    Science

    (1995)
  • K.P. Hummel et al.

    Science

    (1966)
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    Abbreviations used: ob, obese; db, diabetes; fa, fatty;OBR, leptin receptor; OBRb-fa,OBRb offa-type; F-12, Ham's F-12 nutrient mixture; STAT, signal transducers and activators of transcription; MAPK, mitogen-activated protein kinase; JAK, Janus kinase; HSV, Herpes simplex virus; TK, thymidine kinase; CAT, chloramphenicol acetyltransferase; MEK, MAPK kinase; PBS, phosphate buffered saline without Ca2+and Mg2+

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    Correspondence should be addressed to Takashi Murakami, MD. Fax: +81-886-33-9245. E-mail:[email protected].

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