What are the amino acids that signify the sorting signal for peroxisomes?

The sorting signal for peroxisomes is characterized by the presence of the amino acid sequence SKL, which stands for serine (S), lysine (K), and leucine (L). This sequence is recognized by specific receptors in the cytoplasm that facilitate the import of enzymes and other proteins into the peroxisomes. When proteins contain this tripeptide sequence at their C-terminus, it signals the cellular machinery to transport them to the peroxisomes, which are important organelles involved in lipid metabolism and the breakdown of reactive oxygen species.

Understanding the significance of this sorting signal is fundamental in cellular biology, as it highlights how the genetic code translates into specific functional outcomes at the cellular level. Other sequences like AAA, XYZ, and LMN do not have known associations with peroxisomal targeting, making SKL the recognized and validated signal for peroxisome localization.