A Molecular Dissection of Ciliogenesis

Abstract

Cilia are known to be crucial for many developmental and physiological processes, yet cilia biogenesis and maintenance are not well understood. In particular, apart from intraflagellar transport proteins, molecular players in the process of ciliogenesis are largely unknown. Two recent studies utilizing the unicellular green alga Chlamydomonas reinhardtii, which has two flagella that are homologous to human cilia, have determined the proteome of the flagellum and identified genes that are upregulated upon deflagellation. By analyzing these datasets we have identified a set of genes that are upregulated during flagellar regeneration for which the gene products are not components of the flagellum itself, suggesting that there is a class of proteins whose function is to act as cofactors in flagellar assembly. Potential roles for these proteins include chaperones, signaling intermediates, and targeting proteins. We are investigating the functions of ciliogenesis cofactor proteins utilizing knockdown and knockout strategies in Chlamydomonas and ciliated mammalian tissue culture cells.