A Critical Role for Toxoplasma gondii Vacuolar Protein Sorting VPS9 in Secretory Organelle Biogenesis and Host Infection

• Published in: Scientific reports Vol. 6; no. 1; p. 38842
• Main Authors: Sakura, Takaya, Sindikubwabo, Fabien, Oesterlin, Lena K., Bousquet, Hugo, Slomianny, Christian, Hakimi, Mohamed-Ali, Langsley, Gordon, Tomavo, Stanislas
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14.12.2016; Nature Publishing Group
• Subjects: 14; 14/19; 14/28; 631/326/417; 692/699/255; 82; 82/29; 82/80; Biochemistry, Molecular Biology; Cell Line; Guanine; Guanine nucleotide exchange factor; Humanities and Social Sciences; Humans; Life Sciences; Lipids; multidisciplinary; Organelles; Parasites; Protein transport; Proteins; Protozoa; Protozoan Proteins - genetics; Protozoan Proteins - metabolism; Science; Secretory Pathway; Toxoplasma - genetics; Toxoplasma - metabolism; Toxoplasma - pathogenicity; Toxoplasmosis - genetics; Toxoplasmosis - metabolism; Transport Vesicles - genetics; Transport Vesicles - metabolism; Vesicles; Vesicular Transport Proteins - genetics; Vesicular Transport Proteins - metabolism; Virulence
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep38842

Accurate sorting of proteins to the three types of parasite-specific secretory organelles namely rhoptry, microneme and dense granule in Toxoplasma gondii is crucial for successful host cell invasion by this obligate intracellular parasite. Despite its tiny body architecture and limited trafficking machinery, T. gondii relies heavily on transport of vesicles containing proteins, lipids and important virulence-like factors that are delivered to these secretory organelles. However, our understanding on how trafficking of vesicles operates in the parasite is still limited. Here, we show that the T. gondii vacuolar protein sorting 9 ( Tg Vps9), has guanine nucleotide exchange factor (GEF) activity towards Rab5a and is crucial for sorting of proteins destined to secretory organelles. Our results illuminate features of Tg Vps9 protein as a key trafficking facilitator that regulates protein maturation, secretory organelle formation and secretion, thereby ensuring a primary role in host infection by T. gondii .