EIF2AK2 and obesity due to melanocortin 4 receptor deficiency: It is important to highlight that while we conclude that the deletion of PKR does not affect HFD-induced obesity or glucose metabolism, a conclusion that is at odds with the proposed role of PKR in metabolic homeostasis, there are nonetheless several aspects of the phenotype that we describe that are in agreement with previous reports that claim a protective effect of PKR deletion.