Some oncogenes are mutants of normal cell surface receptors

Discussion in 'USMLE STEP 2 CS' started by Jeevan., Aug 4, 2008.

  1. Jeevan.

    Jeevan. Guest

    Some oncogenes are mutants of normal cell surface receptors that have tyrosine protein kinase motifs in their cytoplasmic domains the type of mutation of such a receptor that is most likely to result in cell transformation is a mutant protein with which of the following characteristics ?

    a.-constitutive activation of cellualr transcription
    b.-deletion of the cytoplasmic domain
    c.-failure to become phosphorylated upon receving the signal
    d.-failure to receive the signal that normally activates cellualr trascription
    e.-recognition of a different signal than usual
  2. Guest

    Guest Guest

    Answer is: A. With constitutive activation, the cell will no longer need any signal to begin transcription and that can lead to uncontrolled transcriptuon and thus a tumor.

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