Eukaryotic translation initiation factor 3 subunit K

Eukaryotic translation initiation factor 3 subunit K (eIF3K) is a 218-amino-acid component of the eIF-3 complex, a multi-subunit assembly essential for protein synthesis initiation (UniProt: Q9UBQ5). eIF3K associates with the 40S ribosomal subunit to facilitate recruitment of initiation factors and mRNA scanning for AUG start codon recognition. The eIF-3 complex also selectively regulates translation of mRNAs encoding cell proliferation factors and participates in ribosomal recycling after termination.

eIF3K functions broadly in translational control across human tissues with no primary disease associations documented in UniProt. The protein's selective regulation of mRNA translation involved in cell cycling, differentiation, and apoptosis suggests roles in processes relevant to neuronal homeostasis.

eIF3K shows increased abundance in Alzheimer's disease brain tissue (Chaparral AD proteomics). In post-mortem AD brain versus age-matched controls, the protein was upregulated with a mean log2 fold-change of 0.1953 in human TMT-labeled proteomics analysis. This modest elevation may reflect altered translational control mechanisms or protein synthesis compensation in AD pathology.