The harvest-responsive region of the Asparagus officinalis sparagine synthetase promoter reveals complexity in the regulation of the harvest response

2008 ◽  
Vol 35 (12) ◽  
pp. 1212 ◽  
Author(s):  
Donald A. Hunter ◽  
Lyn M. Watson

The activity of a 1915-bp asparagine synthetase (AS) promoter of Asparagus officinalis L. was induced in mature leaves of transgenic Arabidopsis thaliana (L.) Heynh. plants when the leaves were detached and held in water for 24 h. To understand this induction by harvest, variants of the AS promoter were linked to the β-glucuronidase GUS reporter gene. Harvest induction in the leaves required detachment and was not simply a wound response. Two regions in the AS promoter (Region A, –640 to –523; Region B, –524 to –383) were independently able to confer harvest response to the otherwise unresponsive –383AS (minimal) promoter. Region A was studied in further detail. Various truncations, deletions, or nucleotide substitutions of Region A affected activity and fold induction of the minimal promoter. However, no harvest-inducible cis-acting element within Region A was identified. Although the minimal promoter contained a dehydration-responsive element and ACGT elements similar to ABA-responsive regulatory motifs these were not needed by the upstream regulatory regions for directing harvest response. When four copies of Region A were linked to the minimal promoter it became highly active in leaves before harvest. Deletions within Region A showed that it required its complete 117 bp for driving harvest response, yet the region cannot simply be thought of as a harvest-responsive module, since its concatemerisation led to constitutive expression.

2004 ◽  
Vol 31 (1) ◽  
pp. 63 ◽  
Author(s):  
Somrutai Winichayakul ◽  
Richard L. Moyle ◽  
Simon A. Coupe ◽  
Kevin M. Davies ◽  
Kevin J. F. Farnden

In asparagus (Asparagus officinalis L.), increased levels of asparagine (Asn) and Asn synthetase (AS) transcript are detected during foliar senescence and in harvested spears, possibly triggered by signals from a reduced supply of carbohydrate. To identify cis-elements mediating this regulation, the asparagus AS gene promoter was isolated and analysed by DNA sequencing, followed by expression of AS::GUS (β-glucuronidase) reporter-gene constructs in transgenic tissue, and electrophoretic mobility shift assays (EMSA). The 1958-base pair (bp) region of the AS promoter upstream of the translation initiation ATG (–1958 bp region) was sufficient to confer sucrose (Suc)-regulated expression on the GUS reporter gene in asparagus callus and protoplasts, which were transformed by particle bombardment and electroporation, respectively. Removal of Suc from callus or protoplast media resulted in the induction of GUS activity. Deletion analysis of this 1958-bp fragment identified elements in the –640 to –266�bp region as important for both high GUS levels and mediating the Suc response. This was supported by EMSA results, which showed the formation of three nuclear protein–DNA complexes with the –558 to –284 bp fragment of the promoter. A 20-bp oligonucleotide, designed to match the sequence from –423 to –404 bp, was able to out-compete formation of one of these protein-DNA complexes, suggesting a specific interaction with this sequence. This region of the promoter, overlapping with the 20-bp oligonucleotide sequence, contains a 10-bp stretch identical to a sequence previously shown to mediate low Suc induction of an Oryza sativa (rice) α-amylase gene, and may thus represent a conserved Suc-responsive element.


2004 ◽  
Vol 31 (6) ◽  
pp. 573 ◽  
Author(s):  
Somrutai Winichayakul ◽  
Richard L. Moyle ◽  
Dacey J. Ryan ◽  
Kevin J. F. Farnden ◽  
Kevin M. Davies ◽  
...  

The Asparagus officinalis L. asparagine (Asn) synthetase (AS) promoter was analysed for elements responding to carbohydrate and senescence signals. Transgenic Arabidopsis thaliana L. plants containing deletion constructs of the –1958 bp AS promoter linked to the β-glucuronidase (GUS) reporter gene (AS::GUS) were analysed by measuring GUS specific activity. Inclusion of sucrose (Suc), glucose (Glc) or fructose (Fru) in plant media repressed levels of GUS activity in –1958AS::GUS plants, regardless of the light environment, with increases in GUS found 1 d after incubation on Suc-lacking media. Hexokinase is likely to be involved in the signal pathway, as Suc, Glc, Fru, 2-deoxy-d-glucose and mannose were more effective repressors than 3-O-methylglucose, and the hexokinase inhibitor mannoheptulose reduced repression. Plants containing AS::GUS constructs with deletions that reduced the promoter to less than –405 bp did not show low sugar induction. AS::GUS activity was significantly higher in excised leaves induced to senesce by dark storage for 24 h, compared to fresh leaves, for lines containing at least –640 bp of the AS promoter but not those with –523 bp or smaller promoter fragments. Fusion of the –640 to –523 bp region to a –381AS::GUS construct generated a promoter that retained senescence induction but lacked low sugar induction. Alignment of this region to the 33-bp senescence-related sequence of the Arabidopsis and Brassica napus L. SAG12 promoters identified the sequence TTGCACG as being conserved in all the promoters, and which may be an important senescence-responsive element.


2021 ◽  
Vol 63 (2) ◽  
pp. 60-64
Author(s):  
Thi Ngoc Lan Nguyen ◽  
◽  
Phutthakone Vaciaxa ◽  
Thanh Chung Nguyen ◽  
Huu Quan Nguyen ◽  
...  

Dehydration responsive element binding proteins (DREB) are transcription factors linked to cis-acting elements of the promoter region, which regulate plant gene expression in response to abiotic stress. In this study, 69 DREB gene sequences of soybean from NCBI belonging to 18 GmDREB (Glycine max DREB) genes of 1 to 8 copies distributed on 17 chromosomes were identified in which GmDREB3 has 8 copies and the rest consisted of 1 to 4 ones. The motif PTPEMAARAYDVAALALKGPSARLNFPEL containing 11 points associated with the promoter of functional genes existed in 4 main types with the most popular one RGRRWKERRWT found in 13/18 DREB proteins was regarded as the popular AP2 domain of DREB protein. The phylogenetic tree based on the nucleotide sequences of GmDREB genes and the amino acid sequences of the AP2 domain expresses the evolution and relationship of the DREB subfamily in soybean. This study provides comprehensive information about the DREB subfamily, which formed the basis for experimental analyses to clarify the function of some members of this subfamily.


Author(s):  
Qingchun Zhao ◽  
Zhenzhen Luo ◽  
Jiadong Chen ◽  
Hongfang Jia ◽  
Penghui Ai ◽  
...  

AbstractPhosphorus (P) deficiency is one of the major nutrient stresses restricting plant growth. The uptake of P by plants from soil is mainly mediated by the phosphate (Pi) transporters belonging to the PHT1 family. Multiple PHT1 genes from diverse plant species have been shown to be strongly up-regulated upon Pi starvation, however, the underlying mechanisms for the Pi-starvation-induced (PSI) up-regulation have not been well deciphered for most Pi transporter genes. Here, we reported a detailed dissection of the promoter activity of a PSI rice Pi transporter gene OsPT6, using the β-glucuronidase (GUS) reporter gene. OsPT6 promoter could drive GUS expression strongly in both roots and blades of rice plants grown under low P, but not high P. Cis-acting element analysis identified one copy of the P1BS motif and two copies of the W-box motif in OsPT6 promoter. Targeted deletion of the P1BS motif caused almost complete abolition of GUS induction in response to Pi starvation, irrespective of the presence or absence of the W-box motif, Four repeats of the P1BS motif fused to the CaMV35S minimal promoter was sufficient to induce GUS expression responsive to Pi starvation. Targeted deletion of the upstream W-box motif (W1) did not affect the GUS expression activity compared with the full-length OsPT6 promoter, while targeted deletion of the downstream W-box motif (W2) or both of the W-box motifs remarkably reduced the GUS induction rate upon Pi starvation. Our results proposed that the PSI response of OsPT6 was positively regulated by at least two elements, the sole P1BS and the downstream W-box, in its promoter, and the W-box-mediated up-regulation of OsPT6 might be highly dependent on the P1BS motif.


2000 ◽  
Vol 164 (3) ◽  
pp. R11-R16 ◽  
Author(s):  
A Takenaka ◽  
K Komori ◽  
T Morishita ◽  
SI Takahashi ◽  
T Hidaka ◽  
...  

To investigate the molecular mechanisms of increased transcription of the insulin-like growth factor-binding protein-1 (IGFBP-1) gene in dietary protein-deprived animals, the cis-acting sequence that is involved in this regulation was analyzed. We first showed that IGFBP-1 gene transcription was up-regulated by amino acid deprivation in cultured liver cell lines: H4IIE and HuH-7. Since HuH-7 cells showed a greater increase in IGFBP-1 mRNA in response to amino acid deprivation, this cell line was used in further experiments. Using a promoter function assay, we found that up-regulation of promoter activity responding to amino acid deprivation was abolished by deleting the region between -112 and -81 bp from the cap site from the gene construct. This cis-acting region includes the insulin-responsive element (IRE) and glucocorticoid responsive element (GRE) of IGFBP-1. In summary, the present observation suggests that the 32-bp (-112 to -81) in the IGFBP-1 gene 5' promoter region is involved in the induction of the IGFBP-1 gene in response to amino acid deprivation.


1991 ◽  
Vol 176 (1) ◽  
pp. 233-240 ◽  
Author(s):  
C.L. Xia ◽  
I.G. Cowell ◽  
K.H. Dixon ◽  
S.E. Pemble ◽  
B. Ketterer ◽  
...  

Plants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1033
Author(s):  
Chunying Wang ◽  
Tingting Lin ◽  
Mengqi Wang ◽  
Xiaoting Qi

Ethylene-responsive elements (EREs), such as the GCC box, are critical for ethylene-regulated transcription in plants. Our previous work identified a 19-bp AC-rich element (ACE) in the promoter of bean (Phaseolus vulgaris) metal response element-binding transcription factor 1 (PvMTF-1). Ethylene response factor 15 (PvERF15) directly binds ACE to enhance PvMTF-1 expression. As a novel ERF-binding element, ACE exhibits a significant difference from the GCC box. Here, we demonstrated that ACE serves as an ERE in Arabidopsis. It conferred the minimal promoter to respond to the ethylene stress and inhibition of ethylene. Moreover, the cis-acting element ACE could specifically bind the nuclear proteins in vitro. We further revealed that the first 9-bp sequence of ACE (ACEcore) is importantly required by the binding of nuclear proteins. In addition, PvERF15 and PvMTF-1 were strongly induced by ethylene in bean seedlings. Since PvERF15 activates PvMTF-1 via ACE, ACE is involved in ethylene-induced PvMTF-1 expression. Taken together, our findings provide genetic and biochemical evidence for a new ERE.


1999 ◽  
Vol 340 (2) ◽  
pp. 397-404 ◽  
Author(s):  
Hideki YOSHITOMI ◽  
Kazuto YAMAZAKI ◽  
Isao TANAKA

Uncoupling protein (UCP) 2 is a member of the uncoupling-protein family, and it appears to function as an uncoupler of oxidative phosphorylation. To identify cis-acting regulatory elements controlling this gene's expression, we cloned an approx. 6.2-kb region upstream from the translation-initiation site of the mouse UCP2 gene and analysed its transcription activity using chimaeric mouse UCP2 promoter-placental-alkaline-phosphatase (PLAP) reporter-gene constructs. Sequence analysis showed that the 5ʹ-flanking region of the mouse UCP2 gene was not similar to those of mouse UCP1 or UCP3. For the mouse UCP2, the region near the transcription-initiation site lacked the typical TATA box, but was GC-rich, resulting in presence of several potential specificity protein 1 (Sp-1), activator protein (AP)-1 and AP-2 binding sites. The putative regulatory motifs for muscle-regulatory protein (MyoD), brown-fat regulatory element, CCAAT box, cAMP-response element and Y box were also found in the mouse UCP2 promoter region by computer-assisted analysis. From the results of Northern-blot analysis and transient expression assay, we found that the mouse UCP2 gene responded to the cAMP-dependent protein kinase α-catalytic subunit signal activation at the transcription level. Additionally, deletion analysis of the UCP2 promoter-PLAP constructs indicated that the minimal region exhibiting the promoter activity was located between nt -33 and +100, and that a strong enhancer was present within 601 bp of the 5ʹ-promoter region. In particular, the region from nt -233 to -34 significantly induced PLAP activity in the cell lines derived from various tissues and in the primary culture cells of rat brown adipose tissue, suggesting that this region is most important for the ubiquitous expression of mouse UCP2 mRNA. Furthermore, it was shown that two silencer elements were involved in the mouse UCP2 gene; one was located between nt -2746 and -602, and the other was identified in intron 1. These regions deprived the enhancer of the ability to induce PLAP activity. This study shows a fundamental role for positive and negative cis-acting DNA elements in regulating the basal and cAMP-induced transcription activity of the mouse UCP2 gene.


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