A novel PAR-1-binding protein, MTCL1, plays critical roles in organizing microtubules in polarizing epithelial cells

• DOI: 10.1242/jcs.127845
• Publication Date: 2013-08-01T01:32:45Z
• Authors: Yoshinori Sato; Masashi Akitsu; Yoshiko Amano; Kazunari Yamashita; Mariko Ide; Kyoko Shimada; Akio Yamashita; Hisashi Hirano; Noriaki Arakawa; Takahisa Maki; Ikuko Hayashi; Shigeo Ohno; Atsushi Suzuki
• Keywords: Cell polarity; Polarity (international relations); Basal body; Epithelial polarity; Ciliogenesis

The establishment of epithelial polarity is tightly linked to the dramatic reorganization microtubules (MTs) from a radial array vertical alignment non-centrosomal MT bundles along lateral membrane and meshwork under apical basal membranes. However, little known about underlying molecular mechanism this polarity-dependent remodeling. evolutionarily conserved cell polarity-regulating kinase PAR-1, whose activity essential for maintaining dynamic state MTs, plays indispensable roles promote process. Here, we identify novel PAR-1-binding protein, named MTCL1 (Microtubule crosslinking factor 1), which crosslinks MTs through its N-terminal MT-binding region subsequent coiled-coil motifs. colocalized with apicobasal in cells, knockdown impaired development these specific columnar shape. Rescue experiments revealed that was restoring defects cells. regrowth assays indicated not required initial growth centrosome, but accumulation sublateral regions. Interestingly, recruited subpopulation PAR-1b bundles, interaction MTCL1-dependent bundles. These results suggest mediates cell-specific MT-crosslinking activity, cooperates maintain correct temporal balance between stable within