Lipid-Membrane Binding, Bending, and Pinching

The same points of PM and TGN in my part

The vesiculation machinery is highly redundant at both sites .

Many of the same types of lipid-binding scaffold proteins and classes of lipid-modifying enzymes are used at both sites

Two motifs contained in Many of these lipid-binding proteins

The ENTH/ANTH domain the Epsin N-terminal homology/AP180 N-ter

minal homology domain The BAR domain the Bin-amphiphysin-Rvs161/167p domain

The functions of the ENTH/ANTH domain containing proteins

Deform membrane. Support clathrin-mediated endocytosis or involve in CCV formation at the TGN or TGN a

nd PM.

The BAR domain

The function of the BAR domain: As a mebrane curvature–sensing module. This domain is present in many proteinswith roles in membrane dynamics,including membrane tubulation and ruffling .

N-BAR domain

An unstructured amphipathic helix is present N-terminal to the BAR domain .

The functions of the N-BAR domain containing proteins

sense and induce membrane curvature, presumably toward vesicle formation and scission.

Common membrane-tubulating proteins at the PM and TGN R

R

R

.

Conclusion

A series of related ENTH/ANTH and BAR domain–containing proteins has been superimposed on the clathrin-adaptor sorting machinery to initiate the tubulation and vesiculation of sequestered cargo from both the PM and the TGN.