AtCHX13 T-DNA insertion and transgenic lines. A, Identification of AtCHX13 insertion lines. The positions of two independent T-DNA insertional mutants for AtCHX13 are shown. Lines atchx13-1 and atchx13-2 correspond to SALK lines SALK_095075 and SALK_023605, respectively. Black boxes show exons and lines between them show introns. Arrows labeled with P1 and P2 above and below black boxes show forward and reverse primers used for RT-PCR analysis, respectively. B, Absence of transcripts in T-DNA insertion mutants. RT-PCR was performed from RNA extracted from flowers of wild-type and atchx13 lines. ACTIN1 expression was used as an internal control. C, Characterization of AtCHX13 expression in chx13 mutants. F3 lines of homozygous 35S∷AtCHX13 in Col-0 were used to examine gene expression. Two-week-old seedlings were harvested for RNA extraction and RT-PCR analysis. Transgenic Col-0 plants expressing the vector alone were used as a control and ACTIN1 expression was used as an internal standard.