Figure 5.

The ARG1 gene is expressed ubiquitously in A. thaliana plants. (A) Northern blot analysis of total RNAs extracted from roots (lane 1) or hypocotyls and cotyledons (lane 2) of 8-day-old light-grown seedlings, from hypocotyls and cotyledons of etiolated 5-day-old seedlings (lane 3), or from roots (lane 4), rosette leaves (lane 5), cauline leaves (lane 6), inflorescence stems (lane 7), flowers (lane 8), or siliques (lane 9) of 24-day-old soil-grown plants. The Northern membrane was first hybridized with a ³²P-labeled full-length ARG1 cDNA probe (Upper). After exposure, the blot was stripped and rehybridized with a UBQ4 probe (65) to control for loading differences (Lower). (B) Cytochemical detection of GUS activity in a 3-day-old transgenic A. thaliana seedling carrying the GUS gene fused in-frame within the fourth exon of ARG1.