Caveolin dependent endocytosis

Caveolin Family of proteins mediating caveolin-dependent endocytosis. 

Caveolae-dependent endocytosis occurs in cholesterol- and sphingomyelin-rich flask-shaped invaginations of the cell membrane known as caveolae (67). The shape is determined by a framework constructed by the protein caveolin. The protein binds plasma cholesterol, inserting into... 

It has also been proposed that CPP are taken up by clathrin-independent mechanisms such as caveolin-mediated endocytosis (100). TAT-containing liposomes were colocalized with caveolin 1, a marker for caveolar endocytosis, but not with markers for clathrin (101). An inhibitor of caveolin and nystatin reduced TAT peptide reporter in HepG2 and CHO cells by 50% (80). However, it was pointed out by Brooks et al. that HepG2 cell lines do not contain caveolin 1 (102,103). The caveolin pathways relevance to CPP uptake may depend on the cell type because nystatin inhibits... 

It has been reported that NP internalised via clathrin-dependent endocytosis were generally entrapped within the endosomes and then fused with lysosomes, resulting in lysosomal degradation of the load [74]. On the other hand, NP internalised by caveolin-mediated endocytosis could normally bypass lysosomal degradation [75]. It was also shown that polymeric micelles incorporating nile red (M-NR) were capable of colocalisation with tubulin, an important protein that shapes the microtubule network of cells this colocalisation might be advantageous for M-NR uptake via dynamin and caveolin-mediated endocytosis [76, 77]. 

Depending on the mechanism, endocytosis can also be classified into clathrin-mediated endocytosis [34], caveolin-mediated endocytosis [35], and clathrin- and caveolin-independent endocytosis [36]. Clathrin-mediated endocytosis is a major entry mechanism, and also the most intensely investigated mechanism among the various forms of endocytosis. Although clathrin molecules are involved in most receptor-mediated endocytosis and nonspecific endocytosis, the detailed endocytic mechanism of nonviral carriers has not been well understood yet and has been shown to vary with the size, surface charges, and other characteristics of the carriers. Many carriers use several mechanisms simultaneously, probably due to the intrinsic heterogeneity of the supramolecular structure [37]. 

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