13. Gene Regulation in Eukaryotes

Identical twins each carry the same genome, but over time, can develop different phenotypes. How can you explain this?

What are the possible roles of proteins in histone modification?

What are the roles of the Polycomb and Trithorax complexes in eukaryotic gene regulation?

Describe how reversible chemical changes to DNA and histones are linked to chromatin modification.

Why are changes in nucleosome spacing important in changing gene expression?

Present an overview of the manner in which chromatin can be remodeled. Describe the manner in which these remodeling processes influence transcription.

What are the similarities and differences in the two types of ncRNAs involved in epigenetic control of gene expression?

Chromatin remodeling by the SWI/SNF complex requires hydrolysis of ATP. What purpose does this serve?

The term heterochromatin refers to heavily condensed regions of chromosomes that are largely devoid of genes. Since few genes exist there, these regions almost never decondense for transcription. At what point during the cell cycle would you expect to observe the decondensation of heterochromatic regions? Why?

How do microRNAs regulate epigenetic mechanisms during development?

What are the functions of lncRNAs in epigenetic regulation? Describe each in detail.

What are the different chromatin classifications, and what is their relationship to gene expression?

What is the histone code?

Define epigenetics, and provide examples illustrating your definition.