Final answer:
The formation of an isolation membrane during phagocytosis is triggered by the protein clathrin. This process allows cells to internalize extracellular material, leading to its degradation in endosomes that fuse with lysosomes. The cytoskeleton and associated structures also contribute to membrane compartmentalization which supports processes like phagocytosis.
Step-by-step explanation:
The process you are referring to is known as phagocytosis, which entails the formation of an isolation membrane to encapsulate extracellular material, including cyto components or organelles, for degradation and recycling within the cell. The precursor to this process is a cell membrane adaptation where a protein, specifically clathrin, coats a section of the plasma membrane. Upon recognition of a target particle, this clathrin-coated area of the membrane extends and envelops the material. Subsequently, the clathrin detaches, and the formed vesicle, now an endosome, fuses with a lysosome to break down the encased material.
The formation of the isolation membrane is also related to cellular mechanisms of micro-compartmentalization. The cytoskeleton plays a vital role in maintaining these compartments, sometimes referred to as the Fences and Pickets model, where integral membrane proteins connected to cytoskeletal fibers create barriers, preventing free movement of other membrane components. While this model mostly explains protein positioning within membranes, the overarching concept highlights the cellular ability to compartmentalize and regulate the movement of substances within and across its membrane structures.