The authors introduce a multifunctional control research test bench and its data management and interface system. They implemented a building monitoring, control, and interface system (MCIS) used for ...evaluation of complex building energy systems, for optimization of such energy systems and for carrying out control research experiments. In this paper they explain the MCIS' architecture and functionality, they present its research potential and three different control research use cases for building energy systems and heating, ventilation, and air conditioning (HVAC) systems; model-assisted control parameter fine tuning, model-based predictive control, and demonstration of adaptive control algorithms. The authors outline prerequisites for implementation, demonstration, and evaluation of new developed control algorithms and strategies. These prerequisites are fulfilled via system expansions providing a flexible demonstration bench.
The contribution of sequences upstream and downstream of the transcription start site to the strength and specificity of the promoter of rice tungro bacilliform virus was analysed in transgenic rice ...plants. The promoter is strongly stimulated by downstream sequences which include an intron and is active in all vascular and epidermal cells. Expression in the vascular tissue requires a promoter element located between -100 and -164 to which protein(s) from rice nuclear extracts bind. Elimination of this region leads to specificity for the epidermis. Due to the presence of a polyadenylation signal in the intron, short-stop RNA is produced from the promoter in addition to full-length primary transcript and its spliced derivatives. The ratio between short-stop RNA and full-length or spliced RNA is determined by upstream promoter sequences, suggesting the assembly of RNA polymerase complexes with different processivity on this promoter.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
44.
Splicing in a Plant Pararetrovirus Fütterer, Johannes; Potrykus, Ingo; Brau, Maria Pilar Valles ...
Virology (New York, N.Y.),
02/1994, Letnik:
198, Številka:
2
Journal Article
Recenzirano
Analysis of expression in rice cells of plasmids in which an ATG-less chloramphenicol acetyl transferase ORF was placed in frame with the coding sequence of the pararetrovirus rice tungro bacilliform ...virus (RTBV) ORF IV, and which contained much of the upstream full-length transcript sequence of RTBV, gave evidence to suggest that a splicing event occurred. Reverse transcription/PCR of RNA from transfected protoplasts and from RTBV-infected plants yielded a product which confirmed that the 5′ end of ORF IV was spliced in frame to a short ORF (sORF) in the RTBV leader sequence removing an intron of about 6.3 kb. Most of the translation is initiated at the ATG codon in the sORF with only about 10% at the ORF IV ATG codon. The efficiency of splicing appears to be inversely related to the length of the intron. The finding of splicing in a pararetrovirus blurs the differences between them and retroviruses but is in accord with the hypothesis that retroelements acquire genes and sequences which adapt them to specific niches.
Elements downstream of the transcription start site enhance the activity of the rice tungro bacilliform virus (RTBV) promoter in protoplasts derived from cultured rice cells. This enhancer region was ...located to the first 90 nucleotides of the RTBV leader sequence. Within this region, at least two components which act together to enhance expression from the RTBV promoter could be identified. One is a position- and orientation-independent DNA element within a CT-rich region, and the other is a position-dependent element. Either element was found to be capable of acting independently on a heterologous promoter. The enhancer activity of the DNA element correlates with specific binding of nuclear proteins. Nuclear proteins also recognize an RNA transcript covering the first 90 nucleotides of the RTBV leader
We have studied the influence of the 600 nt long leader sequence of cauliflower mosaic virus 35S RNA on downstream translation. Plant protoplasts were transfected with plasmids expressing a CAT ...reporter gene from a mRNA, containing wild‐type or mutant forms of the 35S RNA leader. Deletion analysis revealed the presence of three separate stimulatory sequence regions, S1, S2 and S3. The latter two interact with each other to enhance downstream translation 5‐ to 10‐fold. This enhancement was not observed in protoplasts from a non‐host plant. In the absence of either S2 or S3, the region I2, located in between, exerts an inhibitory effect on downstream translation, probably due to the presence of short open reading frames. Expression of a reporter gene inserted into I2 increases 2‐fold upon deletion of either S2 or S3. We propose that mRNA regions S2 and S3 form a complex with cellular factors that allows scanning ribosomes to bypass region I2.
Cauliflower mosaic virus sequences have developed as a powerful tool for the study of various aspects of gene expression in plants. Analysis of the promoter/enhancer region has led to the discovery ...of several transcription factors and factor-binding sites. Studies on RNA processing and polyadenylation reveal a viral strategy to obtain terminal redundancy of retrovirus pregenomic RNA. Striking differences between plant and vertebrate polyadenylation signals have been disclosed. The mechanisms for translation of the polycistronic 35S RNA are novel in the eukaryotic field and may give new insight to translational control in general.
Protoplasts from cell suspension cultures of
Oryza sativa (monocot) and
Orychophragmus violaceus (dicot) support transcription from the rice tungro bacilliform virus (RTBV) promoter and translation ...of the resulting mRNA despite the presence of a long leader sequence with strong secondary structure and 12 short open reading frames. Transcriptional elements located both upstream and downstream of the transcription initiation site are defined by deletion analysis and the functional TATA motif is determined. Expression of an open reading frame downstream of the entire leader is more efficient than that downstream of truncated derivatives. For optimal expression sequences in the 5′ and 3′ parts of the leader are required.
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