Abstract
NIP5;1, an aquaporin-like gene, is a boron (B) channel required for normal plant growth under low B conditions and its transcript accumulation is .upregulated under low B (Takano et al., 2006). To elucidate mechanisms of NIP5;1 regulation in response to B, a series of 5'deletions of the upstream promoter region were generated, fused to the GUS reporter gene and introduced into Arabidopsis. The GUS expression analysis revealed that at least three distinct elements in NIP5;1 promoter regions are involved in the expression of three different portions of roots under low B condition.
In a separate set of experiments, NIP5;1 fused N-terminaly to GFP reporter gene was expressed under the control of the promoter NIP5;1 with or without 5'UTR. The observed GFP fluorescence pattern suggested an important role of 5'UTR region in upregulation of NIP5;1 transcript accumulation in response to low B.
