Prokaryote and Eukaryote

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Prokaryote and Eukaryote
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In some cases,
Polycistronic mRNA
operon
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Regulation of Gene Expression

• Transcriptional Regulation
• Post-transcriptional Regulation

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Transcriptional Regulation

• Initiation of transcription
• Sigma factors
• Trans factors
• Cis factors

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Transcriptional Regulation

• Initiation of transcription
• Trans factors
• Activators
• Repressors
• Inducers chemicals, proton,
• Apo-repressors
• Co-repressors

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An example of repressor
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(No Transcript)
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Transcriptional Regulation

• Initiation of transcription
• Cis factors
• Promoters

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-10
-35
-10, TATAAT -35, TTGACA
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Transcriptional Regulation

• Initiation of transcription
• Cis factors
• Operators

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-10
-35
-35
-10
1
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Transcriptional Regulation

• Initiation of transcription
• Cis factors
• Activator sites

1
-10
-35
1
-10
-35
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(No Transcript)
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(No Transcript)
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(No Transcript)
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RNAP
Tryptophan operon
Tryptophan is sufficient
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Tryptophan is insufficient.
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Post-Transcriptional Regulation

• Initiation of translation
• Antisense RNA
• Stability of mRNA
• RNA binding proteins
• Rnases activities

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Post-Translational Regulation

• Proteins are modified
• Phosphorylation, nitrotrosylation
• Co-factor assembly
• Half-life time of proteins
• Proteolysis