The perinuclear Golgi is a subregion of the Golgi apparatus that is located close to the nucleus. It consists of a stack of flattened cisternae that are involved in the processing of newly synthesized proteins and the formation of transport vesicles. The perinuclear Golgi is the site where proteins are modified with various types of oligosaccharides, forming glycoproteins. These modifications are important for protein stability, function, and trafficking. The perinuclear Golgi also plays a role in the formation of lysosomes, which are organelles responsible for cellular digestion.