Group 4 - Gene Regulation in Prokayryotes and Eukaryotes.pptx

molecular biology

1. Saim Hira Umaima Khansa Shoa hassan ​ Gene Regulation In Prokaryotes and eukaryotes

2. Topics to cover Gene regulation 2 Introduction Gene Regulation in prokaryotes Gene regulation in eukaryotes Comparative analysis Conclusion

3. Immobilization 3 Gene regulation is the process by which cells control gene expression, determining when and to what extent specific genes are activated. Gene regulation is crucial for normal cellular function, development, and adaptation to environmental changes 3 Gene Regulation

4. Gene Expression Gene expression, the process by which genetic information is used to synthesize functional proteins, occurs in both prokaryotic and eukaryotic cells Despite similarities, prokaryotic and eukaryotic cells execute gene expression differently due to their structural variations prokaryotic

5. prokaryotic Gene Expression 01 02 Prokaryotic organisms lack a nucleus, and their DNA is present freely in the cytoplasm 03 Protein synthesis involves simultaneous transcription and translation, occurring almost concomitantly Gene regulation in prokaryotic cells primarily operates at the transcriptional level, where transcription halts when proteins are no longer required

6. Eukaryotic Gene Expression 01 02 Eukaryotic cells feature a distinct nucleus where DNA is transcribed into RNA 03 Transcription within the nucleus and subsequent translation in the cytoplasm are separated by the nuclear membrane Regulation in eukaryotic cells occurs at different stages: epigenetic, transcriptional, post-transcriptional, translational, and post translational levels prokaryotic

7. Eukaryotic Gene Expression prokaryotic Transcriptional Control Selecting which genes to transcribe by the cell RNA Processing Control Refining and modifying the pre-mRNA before use Protein Activity Control Modifying the behavior, location, or lifespan of the protein after production RNA Transport and Localization Control Delivering the mRNA to the right cell location for use Translational Control Managing the speed and accuracy of translating the mRNA into a protein. mRNA Degradation Control Deciding how long the mRNA stays before removal or recycling 01 02 03 04 05 06

8. Eukaryotic Gene Regulation prokaryotic Prokaryotic gene regulation occurs at three levels Transcription Level Translational level Post-Translational level Operons are related genes found in a cluster that are transcribed together. Transcription under control of a single promoter. Promoter and Operator Regions Promoter where RNA polymerase binds Operator where regulatory proteins bind Regulatory proteins Repressors Activators Anatomy

9. Eukaryotic Gene Regulation prokaryotic Prokaryotic gene regulation occurs at three levels Transcription Level Post-Translational level Bind to operators Reduces transcription Negative regulation Bind to any DNA binding site Increases transcription Positive regulation Repressor Proteins Activator Proteins Transcription Level

10. Eukaryotic Gene Regulation prokaryotic Prokaryotic gene regulation occurs at three levels Transcription Level Post-Translational level Some operons are usually "off," but can be turned "on" by a small molecule called an inducer Other operons are usually "on," but can be turned "off" by a small molecule called a corepressor. Inducible Operon Repressible Operon Transcription Level Lac Operon Trp Operon

11. Eukaryotic Gene Regulation prokaryotic Prokaryotic gene regulation occurs at three levels Transcription Level Post-Translational level Transcription Level Lac Operon Trp Operon Encodes enzymes for lactose metabolism. Turns on only when the sugar lactose is present. The inducer is allolactose Encodes enzymes for synthesis of tryptophan. Expressed by default, but can be repressed when high levels of the tryptophan are present. The corepressor is tryptophan. Translational level

12. 1 Processing Level 2 Transcription Level 3 Translational level 4 Transport of mRNA 1 2 4 3 Eukaryotic Gene Regulation Eukaryotic Gene Regulation Occurs at Four Levels

13. Eukaryotic Gene Regulation 1 Transcription Level One common method of regulating the expression of eukaryotes genes is to alter the rate of transcription of those genes. Exons Introns Transcription start site Promoter Processing Level 2 3 Translational level 4 Transport of mRNA Transcription Factors Polymerase Enhancers

14. Eukaryotic Gene Regulation 1 Transcription Level The initial mRNA transcript undergoes post-transcriptional modifications in eukaryotes. These include the addition of a 5' cap (a modified guanine nucleotide) and a poly-A tail (a sequence of adenine nucleotides) at the 3' end. Additionally, introns (non-coding regions) are spliced out, and the exons (coding regions) are joined together to form the mature mRNA. . Processing Level 2 3 Translational level 4 Transport of mRNA

15. Eukaryotic Gene Regulation 1 Transcription Level The 5’ methyl guanosine cap and the poly(A) tail collaborate to facilitate exit of mRNAs from the nucleus into the cytoplasm. Proteins in the nucleus participate in the export process A nuclear transport receptor binds along the mature (or maturing) mRNA, a poly-A-binding protein binds along the poly-A tail of the message, and another protein binds at or near the methyl guanosine CAP itself. These interactions enable transport of the mRNA through nuclear pores Transport of mRNA 3 Translational level 4 Processing Level 2

16. Eukaryotic Gene Regulation 1 Transcription Level Translational level 4 Processing Level 2 Transport of mRNA 3 Finally, post-translational modification is an important mechanism for the regulation of gene expression. Nonsense-mediated decay also occurs in eukaryotes. There are many other examples of regulation of gene expression through the regulation of mRNA stability. Translation Regulation

17. 01 Genome Organization 02 Transcriptional Regulation 03 Transcription and Translation Coupling 04 Post-Transcriptional Modifications Comparison Gene Regulation Regulation of Gene Expression DNA Packaging and Chromatin Structure 05 06

18. Genome Organization Comparison Gene Regulation Typically have a singular circular chromosome located in the nucleoid region without a membrane-bound nucleus. Possess multiple linear chromosomes within a membrane-bound nucleus

19. Transcriptional Regulation Comparison Gene Regulation Operons control gene expression. Multiple genes with related functions are transcribed together as a single mRNA. Transcription is more complex and regulated. Transcription factors, enhancers, and promoters play key roles in gene expression.

20. Transcription and Translation Coupling Comparison Gene Regulation Occur simultaneously in the cytoplasm since transcription and translation can happen concomitantly Transcription takes place in the nucleus while translation occurs in the cytoplasm, ensuring separate compartments for these processes.

21. Post-Transcriptional Modifications Comparison Gene Regulation Rarely involve RNA processing. mRNA is usually ready for translation after transcription Pre-mRNA undergoes significant processing (splicing, capping, and tailing) before becoming mature mRNA for translation.

22. Regulation of Gene Expression Comparison Gene Regulation Control gene expression primarily at the transcriptional level, often via operons and regulatory proteins like repressors or activators. Gene expression regulation occurs at multiple levels including transcriptional, post-transcriptional, translational, and post-translational, with a more intricate network involving chromatin remodeling and non-coding RNAs

23. DNA Packaging and Chromatin Structure Comparison Gene Regulation DNA is condensed and organized by histone-like proteins, forming a less structured nucleoid DNA is tightly packed around histone proteins, forming chromatin that undergoes dynamic modifications influencing gene accessibility

24. Cellular Homeostasis Importance Gene Regulation Maintains stable internal conditions. Balances gene activity for stability Cell Differentiation and Specialization Directs cell functions in development Shapes diverse tissue and organ formation. Disease Prevention and Control Facilitates adaptation to shifts. Adjusts gene expression for cues. Response to Environmental Changes Prevents abnormal cell growth. Critical for averting conditions like cancer.

25. Energy Efficiency Importance Gene Regulation Optimizes gene activation for energy Minimizes unnecessary protein synthesis Cell Cycle Regulation Ensures precise cell division control. Prevents uncontrolled cell growth. Aids survival trait development. Fosters adaptation to changing environments.. Adaptive Evolution

26. 26 Advances Detailed insights into gene expression heterogeneity within tissues. Enables study of rare cell types, revealing diverse cellular behaviors Single-Cell Analysis CRISPR-based Precision Precise modulation of gene expression for targeted studies. Higher specificity and efficiency in various cellular contexts

27. Potential for therapeutic interventions targeting epigenetic marks Modification to address diseases associated with abnormal gene regulation. Therapeutics Computational modeling yields holistic insights into gene networks Comprehensive understanding of complex cellular processes. Systems Biology Unveiling additional layers of gene regulation. Identification of potential therapeutic targets in diseases. RNA Research Hi-C advancements deepen understanding of 3D genome impacts Insights into gene regulation, development, and disease. 3D Genome Future Direction

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