KIBRA modulates directional migration of podocytes.
Asymmetric delivery and distribution of macromolecules are essential for cell polarity and for cellular functions such as differentiation, division, and signaling. Injury of podocytes, which are polarized epithelial cells, changes the dynamics of the actin meshwork, resulting in foot process retraction and proteinuria. Although the spatiotemporal control of specific protein-protein interactions is crucial for the establishment of cell polarity, the mechanisms controlling polarity-dependent differentiation and division are incompletely understood. In this study, yeast two-hybrid screens were performed using a podocyte cDNA library and the polarity protein PATJ as bait. The protein KIBRA was identified as an interaction partner of PATJ and was localized to podocytes, tubular structures, and collecting ducts. The last four amino acids of KIBRA mediated binding to the eighth PDZ domain of PATJ. In addition, KIBRA directly bound to synaptopodin, an essential organizer of the podocyte cytoskeleton. Stable knockdown of KIBRA in immortalized podocytes impaired directed cell migration, suggesting that KIBRA modulates the motility of podocytes by linking polarity proteins and cytoskeleton-associated protein complexes.
Duning
Kerstin
K
Medizinische Klinik und Poliklinik D, Universitätsklinikum Münster, Münster, Germany.
Schurek
Eva-Maria
EM
Schlüter
Marc
M
Bayer
Michael
M
Reinhardt
Hans-Christian
HC
Schwab
Albrecht
A
Schaefer
Liliana
L
Benzing
Thomas
T
Schermer
Bernhard
B
Saleem
Moin A
MA
Huber
Tobias B
TB
Bachmann
Sebastian
S
Kremerskothen
Joachim
J
Weide
Thomas
T
Pavenstädt
Hermann
H
D018929:Cell Culture Techniques; D002465:Cell Movement / Q000502:physiology*; D016764:Cell Polarity / Q000502:physiology; D003598:Cytoskeletal Proteins / Q000378:metabolism; D015723:Gene Library; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D010750:Phosphoproteins; D050199:Podocytes / Q000502:physiology*; D011485:Protein Binding; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D062725:Tight Junction Proteins; D020798:Two-Hybrid System Techniques
D003598:Cytoskeletal Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C107903:PATJ protein, human; D010750:Phosphoproteins; D011506:Proteins; D012333:RNA, Messenger; D062725:Tight Junction Proteins; C513637:WWC1 protein, human