eukaryotic promoters
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EUKARYOTIC PROMOTER
Presented by:Manish Gaud.Department: Pharmaco-Informatics(PI-291)NIPER HAJIPUR. 1
Eukaryotic PromotersIn genetics:A promoter is a DNA sequence that can recruit transcriptional machinery and lead to transcription of the downstream DNA sequence. Location:located near the transcription start sites of genes, on the same strand and upstream on the DNA (towards the 5' region of the sense strand). Size:Promoters can be about 100–1000 base pairs long.
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Importance of promoter• Promoter is a binding site for RNA polymerase.• RNA polymerase bind only on promoter.• It helps in transcription.• A promoter may include a binding site for a protein
presence or absence of that protein will affect the strength of the promoter. Such a promoter is known as a regulated promoter.
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•Three kind of RNA polymerase can bind on promoter…• RNA polymerase I • RNA polymerase II• RNA polymerase III
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Types of promoters• 1)Constitutive promoter :-• These promoters are always active for gene expression and
environment independent.
•2)Tissue-specific :-• These promoters direct the gene expression in a specific
tissues or at certain stage of development.
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Types of promoters•3)Synthetic promoter :-• These promoters are made by primary element of a
particular region from diverse origin.
•4)Inducible promoter :-• These promoters dependent upon the external stimuli &
environmental factors for gene expression .
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Method to determine promoter site.
•DNase footprint assay method:
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Online promoter prediction tools
• There are many online tools available for predicting promoter ..• For example,• Promoter 2.0 prediction server.• Neural Network Promoter Prediction.• PROMOSER.• Etc.
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•Promoter 2.0 Prediction Results
• gi_186429_gb_J00265.1_HUMINS01 Human insulin gene, complete 4044 nucleotides
• Position Score likelihood • 2300 1.118 Highly likely prediction • 2900 0.620 Marginal prediction • 3700 0.521 Marginal prediction
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