Which of the following best depicts coordinate control of genes in eukaryotes?

• A. Different genes for proteins involved in a specific metabolic process typically share the same enhancer regions.
• B. Although a group of genes involved in a related metabolic process are typically scattered over different chromosomes, their co-activation is achieved by every gene of the group sharing a specific combination of control elements and activator molecules that bind to them.
• C. Although a group of genes involved in a related metabolic process are typically scattered over different chromosomes, coordinated expression of this group is enhanced by the congregation of loops from different chromosomes in a specific site of the nucleus to form a transcription factory.
• D. The first and second listed responses are correct.
• E. The second and third listed responses are correct.

Answer: (E)

Verified step by step guidance

1. Understand that in eukaryotes, genes involved in the same metabolic pathway can be located on different chromosomes, unlike prokaryotes where they are often organized in operons.
2. Recognize that coordinate control in eukaryotes involves the use of shared regulatory sequences, such as control elements, which are specific DNA sequences that can be bound by transcription factors.
3. Identify that the second option describes a mechanism where genes share a specific combination of control elements and activator molecules, allowing for coordinated activation despite being on different chromosomes.
4. Consider the third option, which describes the physical congregation of chromosomal loops in the nucleus, forming a 'transcription factory' where related genes are co-expressed.
5. Conclude that both the second and third options describe valid mechanisms of coordinate control in eukaryotes, as they both involve strategies for co-regulating genes that are not physically linked.