In general, what are the effects of histone acetylationand DNA methylation on gene expression?

At the molecular level, how do you think a gain-of-function mutation in a developmental gene might cause it to be expressed in the wrong place or at the wrong time? Explain what type of DNA sequence would be altered.

Consider the following three diagrams of a nerve cell membrane. They show resting potential, depolarization, and hyperpolarization. Figure out which one is which, then draw them in the order they occur in a cell that undergoes an action potential outside + Na* inside K* Na* Nat K Nat K Na potential: -80 mV outside + Na K* Na* inside Na+ K Nat Na* K+ potential: +30 mV outside Na Na Na Na* K+ inside K* Na* Kt potential: -70 mV

Methylation of certain lysine residues in histones leads to gene silencing, whereas methylation of other lysine residues in the same histones leads to transcriptional activation. How can methylation lead to these two different outcomes?

Examination of the histone modifications around a gene reveals an abundance of histone H3 with lysine 27 modified with three methyl groups. Does this suggest that this gene is activated or repressed? How would your answer change if many lysine 27 residues were modified with acetyl groups?

(a) Describe how dna binding proteins contact the dna (b)How does the acetylation of lysines on the N-terminal tails of histones influences gene expression?

How does alternative splicing affect gene expression?