Final answer:
Phosphorylation of eIF-2α impedes protein synthesis by preventing the formation of the initiation complex, which could contribute to the progression of neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's.
Step-by-step explanation:
Phosphorylation of eIF-2α makes it unavailable for protein synthesis. When eIF-2 is phosphorylated, it undergoes a conformational change that prevents it from binding to GTP, which is a necessary step for the formation of the initiation complex in protein synthesis. Hence, phosphorylation of eIF-2α impedes the formation of the initiation complex, leading to a decrease in protein synthesis. This is particularly significant in the context of neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's, where an increase in phosphorylation of eIF-2 has been observed; this could result in diminished protein synthesis, potentially contributing to the disease process.