The effects of mDia1 and truncated mutants of mDia2 on stable MT formation in human cells. The 293A cells were transfected with GFP, mDia1-GFP, or GFP-tagged truncation mutants of mDia2 containing FH1FH2CC, FH1FH2, FH2CC, FH1, FH2, and CC. At 48 h after transfection, cells were fixed and stained for tyrosinated tubulin (Tyr-MTs) and detyrosinated tubulin (Glu-MTs). (Scale bar, 20 μm.) Similar results were obtained in at least three independent experiments.