Which of the following methods is used to study protein interactions in live cells?

Hereditary spherocytosis (HS) is a disorder characterized by sphere-shaped red blood cells, anemia, and other abnormal traits. Ankyrin-1 (ANK1) is a protein that links membrane proteins to the cytoskeleton. Loss of this activity is associated biochemically to HS. However, Gallagher et al. (2010) (J. Clin. Invest. 120:4453–4465) show that HS can also be caused by mutations within a region from -282 to -101 relative to the transcriptional start site, which lead to constitutive transcriptional repression in erythroid cells due to local chromatin condensation. Propose a hypothesis for the function of the -282 to -101 region of the ANK1 gene.

Transcription factors play key roles in the regulation of gene expression, but to do so, they must act within the nucleus. Like most proteins, however, transcription factors are translated in the cytoplasm. To enter the nucleus, transcription factors contain nuclear localization signals, which in some cases can work only when bound to some other molecule such as a steroid hormone. After entering the nucleus, transcription factors must bind to appropriate DNA sites and must interact with other transcription proteins at promoters, enhancers, and silencers. Transcription factors then activate or repress transcription through their activation or repression domains. Many drug therapies target transcription factors. Based on the information provided above, suggest three specific mechanisms through which a successful drug therapy, targeted to a transcription factor, might work.

Which of the following terms describes the study of physical interactions between DNA, RNA, and Protein?

Which of the following methods is used to study protein-DNA interactions?

In this chapter, we focused on the analysis of genomes, transcriptomes, and proteomes and considered important applications and findings from these endeavors. At the same time, we found many opportunities to consider the methods and reasoning by which much of this information was acquired. From the explanations given in the chapter, what answers would you propose to the following fundamental questions?

How have microarrays demonstrated that, although all cells of an organism have the same genome, some genes are expressed in almost all cells, whereas other genes show cell- and tissue-specific expression?