Tie1 contains an Akt consensus phosphorylation site and can be phosphorylated <i>in vitro</i> by Akt.

Abstract

<p><b>a</b> The juxtamembrane (JM) domain of Tie1 is highly conserved from zebrafish through humans (light gray), including a high probability Akt phosphorylation consensus sequence (RRRTFTY) within the JM region (dark gray). The predicted phosphorylation site at Tie1-Thr794 is not present in Tie2. <b>b</b> GST-Tie1 fusion protein was incubated with EC lysates that had been infected with AdEmpty (-) or AdmyrAkt (+) virus in an <i>in vitro</i> kinase reaction. Phosphorylated Tie1 (arrow) was detected with a phospho-Akt substrate antibody. <b>c</b> HUVECs expressing Tie1WT, -T794A, or Tie2 were infected with AdEmpty (-) or AdmyrAkt (+) and Tie1 or Tie2 was immunoprecipitated (IP) and probed with a phospho-specific Tie1-pT794 antibody.</p