Final answer:
Cisternal maturation involves the forward movement and maturation of Golgi cisternae, rather than retrograde trafficking of Golgi proteins. It entails successive modifications of proteins and lipids ultimately resulting in their packaging into vesicles for various destinations.
Step-by-step explanation:
Cisternal maturation is a process within the Golgi apparatus where proteins and lipids received from the endoplasmic reticulum (ER) are modified, sorted, and packaged. The Golgi apparatus has different regions: cis-Golgi network, medial-Golgi, endo-Golgi, and trans-Golgi network. Proteins initially undergo modifications such as glycosylation and phosphorylation as they move from the cis face to the trans face, acquiring signals for their final destinations.
Contrary to retrograde transport, cisternal maturation primarily involves the forward (anterograde) movement of the cisternae through the Golgi while carrying and modifying their cargo. The modified cargo is then packaged into vesicles that bud from the trans face of the Golgi. After leaving the trans Golgi network, these vesicles either merge with the plasma membrane to secrete their contents outside the cell or move to other organelles within the cell.