Öz
26S proteasome non-ATPase subunit 4 (PSMD4) that has a molecular weight of 41 kDa is included on
chromosome 1 (1q21.3). PSMD4 protein is a subunit of the 19S regulatory region in the 26S proteasome.
The proteasome breaks down proteins that are not needed or non-functional in the cell. We have limited data
about the regulation of this gene in the literature. In our research, changes in the mRNA and protein levels
of the PSMD4 gene were investigated in different cancer cell lines (prostate, breast, colon, cervix, hepatoma,
osteosarcoma and pancreas) and a normal cell (human vein endothelial cell). The highest expression of PSMD4
gene was seen in HUVEC and PC-3 cells. Bioinformatic analysis was also performed on PSMD4 protein for
different species namely human, mouse and rat. Our Bioinformatic analyses showed that first 250 nucleotides
are much conserved in all three species.