Dr. Ines Subota
fon: +49 (0)931 31 86476
Ines Subota is a cell biologist with special interest in parasitology. Ines studied biology at the Ludwig-Maximilians-Universität München where she got in contact with working on trypanosomes. After a short excursion into the field of protein biochemistry during her diploma thesis at the Max-Planck-Institut of Biochemistry, she sought to work on parasites during her PhD. At the Institut Pasteur in Paris she investigated molecular and cellular aspects of trypanosome differentiation in the tsetse fly during four years. In October 2011 she obtained her doctorate in biology from the Julius-Maximilians-Universität Würzburg. Since then she continues research on trypanosomes in the Department of Cell and Developmental Biology as a postdoctoral fellow.
The Trypanosoma brucei parasite cycle involves a veritable journey through the tissues of a mammalian host and a tsetse fly vector during which the trypanosome cell adopts at least nine developmental stages. Likely, each parasite form is the best adapted to its specific microenvironment and task. Ines doctoral thesis dealt with two main questions of how trypanosome differentiation is controlled. First, which proteins could be involved in the developmental fine-tuning of mRNA levels during stage differentiation, when modifications of the gene expression program almost completely rely on post-transcriptional control? Second, which proteins play a role in sensing the environment in order to trigger differentiation at the right step in the right place?
Ines demonstrated that the RNA-binding proteins ALBA are involved in specific differentiation processes during the trypanosome development in the tsetse fly. They are expressed in all forms of the parasite cycle except in those found in the flies’ proventriculus. ALBA protein knockdown and overexpression experiments at specific stages proved their contribution to morphological changes typical of differentiation processes. The hypothesis that ALBA proteins control developmental gene expression programs came from experiments showing their colocalization with mRNA and known RNA-binding proteins in RNA-granules. These granules are forming as a consequence of stress conditions and are presumed to play an important role in translational control of mRNA transcripts. Environmental triggers are presumed to activate specific sensing pathways that are at the initiation of differentiation events, leading to the next form in the parasite cycle. In the second part of her thesis, Ines focused on the trypanosome flagellum, which is a good candidate to be the sensing organelle of the cell. Several proteins were selected from an available proteomic analysis of intact flagella and analyzed by tagging experiments. These experiments led to the identification of a novel flagellar membrane protein and several flagellar matrix proteins showing different localization pattern and turnover dynamics. RNAi experiments were initiated in order to show their possible role in sensing external stimuli.
Subota I, Julkowska D, Vincensini L, Reeg N, Buisson J, Blisnick T, Huet D, Perrot S, Santi-Rocca J, Duchateau M, Hourdel V, Rousselle JC, Cayet N, Namane A, Chamot-Rooke J, Bastin P. (2014). Proteomic analysis of intact flagella of procyclic Trypanosoma brucei cells identifies novel flagellar proteins with unique sub-localisation and dynamics. Mol Cell Proteomics. 2014 Apr 16.
Rotureau B, Subota I, Buisson J, Bastin P. (2012) A new asymmetric division contributes to the continuous production of infective trypanosomes in the tsetse fly. Development. 2012 May;139(10):1842-50. doi: 10.1242/dev.072611.
Subota I, Rotureau B, Blisnick T, Ngwabyt S, Durand-Dubief M, Engstler M and Bastin P (2011). ALBA proteins are stage regulated during trypanosome development in the tsetse fly and participate in differentiation. Molecular Biology of the Cell 22(22):4205-19