Chapter 218 - Cdc42 and Its Cellular Functions

Abstract

This chapter provides a general appreciation for the different cellular processes that come under the regulation of Cdc42, and then alludes to some of the current challenges confronting investigators. The initial discovery of a mammalian/human homolog for the product of the yeast CDC42 gene suggests that GTPase must play a fundamentally important role in cell biology. Cdc42 participates in the regulation of a wide variety of cellular functions aside from its role in the establishment of cell polarity, including gene transcription, cell-cycle progression, vesicular trafficking, and receptor endocytosis. The small GTPases play fundamentally important roles in cell biology, functioning as molecular switches in cellular signaling pathways and other biological processes. Future efforts are likely to be directed at understanding how the proper GEFs and target/effectors are positioned to enable Cdc42 to efficiently trigger its many different cellular responses, and whether these various activities need to be coordinated such that the effects of Cdc42 on cell growth can be synchronized with its regulation of cell shape and movement.