Université Paris Sud

2 ARTICLES PUBLISHED IN JoVE

Immunology and Infection

Imaging Ca²⁺ Responses During Shigella Infection of Epithelial Cells

Yasmine Smail^1,2,3,4, Chunhui Sun^1,2,3,4, Laurent Combettes⁵, Guy Tran Van Nhieu^1,2,3,4

¹Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, ²Institut National de la Santé et de la Recherche Médicale (Inserm), U1050, ³Centre Nationale de la Recherche Scientifique (CNRS), UMR7241, ⁴MEMOLIFE Laboratory of Excellence and Paris Sciences et Lettres, ⁵Inserm, UMRS1174, Université Paris Sud

Here, we present protocols to visualize calcium (Ca²⁺) responses elicited by HeLa cells infected by Shigella. By optimizing the parameters of bacterial infection and imaging with Ca²⁺ fluorescent probes, atypical global and local Ca²⁺ signals induced by bacteria over a large range of infection kinetics are characterized.

Biochemistry

Purification of Tubulin with Controlled Posttranslational Modifications and Isotypes from Limited Sources by Polymerization-Depolymerization Cycles

Satish Bodakuntla^*1,2, A.S. Jijumon^*1,2, Carsten Janke^1,2, Maria M. Magiera^1,2

¹PSL Research University, CNRS UMR3348, Institut Curie, ²Université Paris-Saclay, CNRS UMR3348, Université Paris Sud

This protocol describes tubulin purification from small/medium-scale sources such as cultured cells or single mouse brains, using polymerization and depolymerization cycles. The purified tubulin is enriched in specific isotypes or has specific posttranslational modifications and can be used in in vitro reconstitution assays to study microtubule dynamics and interactions.