Figure 7.

Steady-state mRNA levels of DcSUT1 and DcSUT2 in leaf lamina and sections of the stem. Top, Leaves of about 12-week-old plants that had not yet reached their mature size were dissected into lamina and six consecutive stem sections. A, A northern blot with total RNA (10 μg/lane) from leaf lamina (L) and stem sections (sections 1–6 from top to bottom; section 1 was a highly branched stem segment connecting the numerous leaf lamina) was hybridized with a ³²P-labeled probe for DcSUT1. B, A blot identical to that in A was hybridized with a ³²P-labeled probe for DcSUT2. As a probe for a constitutively expressed gene, a fragment of the 18S rRNA gene from tomato was used.