PRR2 dimerization and phosphorylation. (A) Da-1/PRR2δ me and Da-1/PRR2 me transfectants were immunoprecipitated with PRR2δ and PRR2 antisera, respectively. The ECV304 (B) and the TF-1 (C) cell lines were immunoprecipitated with the MoAb R2.477. Immunoprecipitation was performed in the absence (−) or presence (+) of BS3 cross-linker. Blots were then hybridized with a mix of PRR2 and PRR2δ immunesera. (D) Da-1/PRR2δ hi cells were immunoprecipitated with the PRR2δ immuneserum and blot was first analyzed with the 4G10 MoAb, stripped, and incubated with PRR2δ immuneserum. Molecular weight markers were from Biolabs. / and δ/δ represent PRR2 and PRR2δ homodimeric forms, respectively. /δ represents the PRR2 and PRR2δ heterodimeric form.