Figure 8.

Molecular and phenotypical analysis of transgenic maize containing the ZmMCM6 gene under control of the strong and constitutive maize UBI promoter. A, Examples of Southern blots containing 10 μg genomic DNA of transgenic lines with ZmMCM6 constructs in sense (SE, left) and antisense (AS, middle) orientation, or fused with GFP (G, right). Genomic DNA was digested with enzyme combinations to display full-copy integrations (arrowheads). Left and middle blots were hybridized with a ZmMCM6-specific probe and the right blot with a GFP-specific probe. The control (A188) on the blot in the middle shows the endogenous ZmMCM6 signal. B, Transgenic plants containing a functional ZmMCM6 AS construct were small in size and did not develop cobs to maturity. Tassels contained little pollen. Here, the clonal line AS4a to AS4c is shown. The line AS10a lacking a functional transgene is shown at the left. Plant height of AS10a was comparable to wild-type plants (A188; 160–190 cm) and both a cob and tassel were fully developed. The white ruler in flower pots is 25 cm.