DP1 does not undergo constitutive internalization.

<p>Cell surface receptor expression was measured by ELISA as described under “<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0065767#s2" target="_blank">Materials and Methods</a>” in HEK293 transiently co-transfected with pcDNA3-Flag-DP1 or pcDNA3-Flag-TPβ in combination with pcDNA3 or pcDNA3-dynamin-K44A, a dominant negative mutant of dynamin. Data are shown as the percentage of cell surface receptor expression in cells co-transfected with pcDNA3 for each receptor. Results are the mean ± S.E. of at least three independent experiments. ** is <i>P</i><0.01.