Pex5PEX7receptoren

Pex5PEX7 receptors represent a crucial component of the peroxisomal protein import machinery. Peroxisomes are vital organelles found in eukaryotic cells that perform a variety of metabolic functions, including lipid metabolism and detoxification. The proper functioning of peroxisomes relies on the import of specific proteins from the cytoplasm.

Two principal receptor proteins, Pex5 and Pex7, are central to this import process. Pex5 recognizes and binds to proteins containing a peroxisomal targeting signal type 1 (PTS1), while Pex7 recognizes and binds to proteins containing a peroxisomal targeting signal type 2 (PTS2). These signals are short amino acid sequences present on the cargo proteins that act as zip codes, directing them to the peroxisome.

Following recognition, the receptor-cargo complex is translocated through a pore-like structure in the peroxisomal membrane, facilitated by other peroxisomal proteins. Once the cargo protein is successfully delivered into the peroxisomal lumen, the receptor is typically recycled back to the cytoplasm to mediate further import cycles. The dynamic interaction between Pex5, Pex7, their respective cargo proteins, and the peroxisomal membrane is tightly regulated to ensure efficient and accurate protein import. Defects in these receptors or their associated machinery can lead to peroxisomal biogenesis disorders, a group of severe genetic diseases.