Cell polarity and endocytosis

Multicellular organisms have to generate asymmetries in cells and tissues to create different organs. Moreover, several responses to environmental factors are directional and hence require an equal directional response. In plants, such a challenge is accomplished by a multitude of polarly localized proteins that are involved in embryonic and post-embryonic development and dynamic polar responses to the environment. The phytohormone auxin and its polar cell to cell transport play a key role in several of those events providing a mean to coordinate cell and tissue polarities through regulating the polar localization of plasma membrane localized PIN auxin transporters. In this chapter, we discuss the crosstalk between cell trafficking and polarity as a way to integrate external as well as internal signals into asymmetry generation and directional responses in the context of PIN localizations and auxin-dependent processes