Deletion analysis of a nitrite-reductase promoter from spinach in transgenic tobacco

Abstract

Abstract. Deletion analysis of the nitrite-reductase (NiR) promoter from spinach (Spinacia oleracea L.) fused to the fl-glucuronidase (GUS) reporter gene and introduced into tobacco (Nicotiana tabacum L., cv. Coker 176) indicates that basic elements required for light-and nitratedependent expression of the reporter are located within the promoter sequence -200/+ 131 relative to the transcription-initiation site. Detailed analysis indicates that positive regulatory elements exist between -200 and -330 as well as between -1450 and -1730, stimulating the level of GUS gene expression under all experimental conditions. Induction/reversion light-pulse experiments show that the promoter sequence -200/+ 131 suffices for phytochrome-mediated expression of the reporter gene. The observation that the NiR promoter from spinach exhibits full reversibility in transgenic tobacco confirms the previous conclusion that the NiR promoter from spinach fused to a GUS reporter gene and introduced into tobacco responds to nitrate and phytochrome as would be expected for tobacco (host) and not as would be expected for spinach (donor). When the plastids were damaged by photooxidation in the presence of Norflurazon, GUS activity levels were reduced to the same extent for all NiR-promoter/GUS fusions tested, indicating that the promoter region involved in the action of the 'plastidic factor' is between -200 and + 131. The GUS gene expression under the control of the CaMV-35S promoter is not affected by light, nitrate or the 'plastidic factor'.

Light Regulation of Nitrate uptake, Assimilation and Metabolism

“…Promoter analysis of bean (Sander et al 1995), spinach (Rastogi 1993, Neininger et al 1994, Sivasankar et al 1998 tobacco (Dorbe et al 1998) and birch (Warning and Hachtel 2000) have revealed cis-acting elements involved in nitrate induction of NII transcription. Promoter analysis was performed by linking the promoters, or promoter fragments, to a reporter gene, and introducing this into tobacco, or in one case (Dorbe et al 1998) Arabidopsis.…”

Sequences Necessary for Nitrate-Dependent Transcription of Arabidopsis Nitrate Reductase Genes

“…These results indicate that NP1 and NP2 contain the cis-acting elements necessary for nitrate-dependent transcription. Nitrate not only increases the transcription of NR genes, but also increases the transcription of NiR genes (Rastogi et al, 1993;Neininger et al, 1994;Sander et al, 1995).…”

Truncated Cotton Subtilase Promoter Directs Guard Cell-Specific Expression of Foreign Genes in Tobacco and Arabidopsis

“…This suggests that the (T/A)AAAG elements, especially TAAAG, proximal to TSS might determine guard cell specific expression of the gene, whereas those far away from the TSS might not only do not work for, but also impede the guard cell specificity. Neininger et al [64] and Dorbe et al [65] observed that in spinach and tobacco NIR gene promoters, the sequences close to their TSS were sufficient to confer nitrate-responsive increases in reporter enzyme activity. Besides the position effect of (T/A)AAAG relative to the TSS, the distance in (T/A)AAAG clusters and/or the distance between clusters and coding region may affect guard cell specific expression, for which the Kat1 [33] is exampled.…”