In the inherited disorder Wiskott-Aldrich syndrome, __________.

• A. muscle cells lack the appropriate membrane receptor
• B. nerve cells lack the ability to produce cAMP
• C. G proteins are unable to phosphorylate GDP
• D. the endoplasmic reticulum is unable to store calcium
• E. a multifunctional relay protein involved with the proliferation of immune cells is defective

Answer: (E)

Verified step by step guidance

1. Understand the context of Wiskott-Aldrich syndrome, which is a genetic disorder affecting the immune system.
2. Recognize that the problem is asking about a specific defect related to the syndrome.
3. Identify the options provided and note that they describe different cellular or molecular dysfunctions.
4. Focus on the correct answer, which involves a defect in a multifunctional relay protein crucial for immune cell proliferation.
5. Conclude that the defect in Wiskott-Aldrich syndrome is related to a protein that plays a role in signaling pathways necessary for immune cell function.