Loss of the Protein IFT57 Reduces Intraflagellar Transport Complex B Stability in Chlamydomonas reinhardtii

Abstract

The intraflagellar transport (IFT) protein complex is a vital component needed for the maintenance and generation of the cellular organelle flagellum or cilium. This process is termed ciliogenesis. The complex is comprised of two sub-complexes, A and B, each containing multiple protein subunits that are responsible for the delivery of flagellar assembly proteins along the proximal and distal end of the flagella organelle. Chlamydomonas reinhardtii is used as a model organism for studying the IFT machinery as it possesses a highly conserved IFT protein complex similar to that in humans. Previous research has shown that defects in the flagellar assembly process and in the IFT machinery, may lead to human diseases termed ciliopathies. The aim of this study is to utilize an IFT complex B mutant (2p40) deficient in the protein IFT57 to determine this protein’s role in the proper function of the IFT complex and ciliogenesis. Data characterizing this IFT57 mutant shows complex B proteins are highly reduced in 2p40 when compared to wild type cells. A western blot assay of the mutant was used to determine if IFT57 does or does not affect the stability of the IFT complex. The data suggests the reduced level of IFT57 within the cell reduces the stability of the IFT B complex. Previous and ongoing research shows IFT57 is involved in the pathology of the human ciliopathy Huntington’s disease; therefore, further investigation of IFT57’s role in the IFT complex and ciliogenesis could aid in the innovation of ways in which to treat this disease.