University of the Basque Country, UPV/EHU 3 articles published in JoVE Immunology and Infection Subcellular Fractionation from Fresh and Frozen Gastrointestinal Specimens Irati Romero-Garmendia*1, Amaia Jauregi-Miguel*1, Izortze Santin2, Jose Ramón Bilbao1, Ainara Castellanos-Rubio1 1Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country (UPV-EHU), Biocruces Health Research Institute, 2Endocrinology and Diabetes Research Group, Biocruces Health Research Institute, UPV-EHU, CIBERDEM Here, we present a protocol to perform a simple cellular fractionation for the subcellular separation of cytoplasmic and nuclear proteins in human fresh and frozen intestinal biopsies. Genetics Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols Aintzane Apraiz*1, Jone Mitxelena*2,3, Ana Zubiaga2 1Department of Cell Biology and Histology, University of the Basque Country, UPV/EHU, 2Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country, UPV/EHU, 3Department of Molecular Mechanisms of Disease, University of Zurich We report two cell synchronization protocols that provide a context for studying events related to specific phases of the cell cycle. We show that this approach is useful for analyzing the regulation of specific genes in an unperturbed cell cycle or upon exposure to agents affecting the cell cycle. Biology The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example Brendan M. O'Leary1, Arantza Rico2, Sarah McCraw1, Helen N. Fones3, Gail M. Preston1 1Department of Plant Sciences, University of Oxford, 2School of Education of Vitoria-Gasteiz, University of the Basque Country (UPV/EHU), 3Biosciences, University of Exeter This protocol details the optimized extraction of apoplast washing fluid from plant leaves, using French bean plants (Phaseolus vulgaris) as a model example.