Lifeact-mEGFP in Plant Cells Figure 6. GFP and Lifeact-mEGFP have equivalent effects on lily pollen tube growth. (A) Lily pollen was transformed with 3.0 mg of GFP or Lifeact-mEGFP, imaged, then average fluorescence per pixel and pollen tube length were measured. (B) Lily pollen transformed with Lifeact-mEGFP. DIC image series of at least 4 minutes were collected of transformed and untransformed pollen on the same slide. Error bars indicate standard error (n = 9 for untransformed and n = 12 for transformed, t-test p = 0.4472). (C) Pollen transformed with increasing amounts of DNA of both GFP (light grey) and Lifeact-mEGFP (dark grey) were fixed after three hours, imaged and measured. No difference in length distribution is apparent. (D) Representative images of pollen tubes expressing Lifeact-mEGFP that have stopped growing, but still exhibit cytoplasmic streaming. doi:10.1371/journal.pone.0005744.g006 PLoS ONE | www.plosone.org 9 May 2009 | Volume 4 | Issue 5 | e5744