Cell Polarity in the Budding Yeast Saccharomyces Cerevisiae

Abstract

This chapter reviews the different steps and components involved in polarized growth in vegetative, pseudohyphal, and mating yeast cells. Polarized cell growth and polarized cell division are two basic processes important for both unicellular and multicellular organisms. Polarized cell growth is crucial for producing precise cellular structures and shapes that help mediate the specialized functions of distinct cell types. Polarized cell divisions occur at critical times in development and are responsible for directing appropriate cell–cell contacts, mediating growth in a specific direction, and establishing cytoplasmic differences between two daughter cells. Thus, both polarized growth and polarized divisions are essential for the development of tissues and entire organisms. Bud formation and projection formation are distinct mechanisms for polarized cell growth, and in the past years, a wealth of information about how these processes occur has been generated. Many of the components involved in polarized cell growth in yeast, including both structural components such as actin and regulatory components, such as mitogen-activated protein-kinase pathways and Rho proteins, are remarkably conserved in structure and in function with other eucaryotic cell types.