#Question id: 4534
#Unit 3. Fundamental Processes
The yeast Saccharomyces cerevisiae divides by budding: instead of dividing to produce two identical daughter cells, the so-called mother cell buds to produce a daughter cell, The HO gene is expressed only in mother cells and only at a certain point in the cell cycle,
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			 1. SBF  | 
			
			 I- Which is active only during the G1-S transition of the cell cycle.  | 
		
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			 2. SWI5  | 
			
			 II-Which acts only in the mother cell.  | 
		
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			 III- Recruit nucleosome modifiers  | 
		
#Question id: 4535
#Unit 3. Fundamental Processes
The activators bind—and the enhanceosome forms—in a highly cooperative manner, ensuring that all three activators must be present. The following are three ways the regulators might be binding cooperatively:
I- Through direct protein–protein interactions between them
II- By changes in the DNA caused by binding of one protein helping binding of another;
III- By the fact that the activators all interact simultaneously with the coactivator.
#Question id: 4536
#Unit 3. Fundamental Processes
The human b-interferon gene is activated in cells upon viral infection through some activators, EXCEPT one
#Question id: 4537
#Unit 3. Fundamental Processes
The enhancer DNA is __, but once the activators are bound it is relatively , HMGA1 the DNA and thus helps the final structure form.
#Question id: 4538
#Unit 3. Fundamental Processes
We first consider a generic case. Gene A is controlled by four signals (1, 2, 3, and 4), each working through a separate activator (activators 1, 2, 3, and 4). Gene B is controlled by three signals (3, 5, and 6), working through activators 3, 5, and 6. It shows-
#Question id: 4539
#Unit 3. Fundamental Processes
The yeast S. cerevisiae exists in three forms: two haploid cells of different mating types—a and alpha and the diploid formed when an a and an a cell mate and fuse. The a cell and the a cell each encodes cell-type-specific regulators: a cells make the regulatory protein a1, and alpha cells make the proteins alpha1 and alpha2. A fourth regulatory protein, called Mcm1, is also involved in regulating the mating-type-specific genes (and many other genes) and is present in both cell types which shows Combinatorial Control.
The arrangement of regulators at the promoters of a-specific genes and a-specific genes is
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			 cell type:  | 
			
			 gene regulatory proteins:  | 
			
			 target genes:  | 
		
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			 1.a cell (haploid)  | 
			
			 a1 Mcm1  | 
			
			 aSG alphaSG  | 
		
| 
			 2.αlpha cell (haploid)  | 
			
			 alpha 1 alpha 2 Mcm2  | 
			
			 hSG  | 
		
| 
			 3.a/αlpha cell (diploid)  | 
			
			 a1 Mcm2 alpha2  | 
			
