Related Experiment Video For MDCK cells
Updated: Mar 17, 2026

Isolation of Glomeruli and In Vivo Labeling of Glomerular Cell Surface Proteins
Published on: January 18, 2019
Regulation of podocalyxin trafficking by Rab small GTPases in epithelial cells
Paulina S Mrozowska1, Mitsunori Fukuda1
1a Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences , Graduate School of Life Sciences, Tohoku University , Sendai, Miyagi , Japan.
Abstract:
The characteristic feature of polarity establishment in MDCK II cells is transcytosis of apical glycoprotein podocalyxin (PCX) from the outer plasma membrane to the newly formed apical domain. This transcytotic event consists of multiple steps, including internalization from the plasma membrane, transport through early endosomes and Rab11-positive recycling endosomes, and delivery to the apical membrane. These steps are known to be tightly coordinated by Rab small GTPases, which act as molecular switches cycling between active GTP-bound and inactive GDP-bound states. However, our knowledge regarding which sets of Rabs regulate particular steps of PCX trafficking was rather limited. Recently, we have performed a comprehensive analysis of Rab GTPase engagement in the transcytotic pathway of PCX during polarity establishment in 2-dimensional (2D) and 3-dimensional (3D) MDCK II cell cultures. In this Commentary we summarize our findings and set them in the context of previous reports.
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