Expression data from root tissues of 35S:AtHMA4 and wild-type tomato plants grown in the presence of Zn

Ectopic expression of AtHMA4 in tomato modified Zn accumulation in a Zn-supply dependent manner. It suggests that HMA4-expression under a range of Zn-supply differentially modifies the expression of endogens, which contributes to different Zn-related phenotypes. To identify genes differentially regulated in 35S:AtHMA4-expressing and wild-type tomato, the transcription profiles were compared between roots of transgenic and WT-plants grown in the presence of 5 µM Zn. An effort was undertaken to recognize tissue specific alterations underlying the difference in Zn root:shoot distribution between tested plant lines and LCM technique was used to isolate epidermis+cortex and stele from roots.Understanding the interplay between the transgene and the endogens is crucial for planning genetic modification for Zn-biofortification purpose. 10-day old tomato plant (35S:AtHMA4 expressing and WT) were subjected to 5 µM Zn (added as ZnSo4) for 15 days. Three independent experiments were performed. At the end of each experiment 2.0 cm long root fragments from six plants (excluding 1.5 cm long apical fragments) were pooled, embedded in NEG-50 Frozen Section Medium (Thermo Scientific), and frozen in liquid nitrogen. Total RNA isolated from three batches of roots was amplified and used for three independent microarray analysis.