Details

Autor(en) / Beteiligte

• Park, Frederick D.
• Tenlen, Jennifer R.
• Priess, James R.

Titel

C. elegans MOM-5/Frizzled Functions in MOM-2/Wnt-Independent Cell Polarity and Is Localized Asymmetrically prior to Cell Division

Ist Teil von

• Current biology, 2004-12, Vol.14 (24), p.2252-2258

Ort / Verlag

England: Elsevier Inc

Erscheinungsjahr

2004

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• C. elegans embryonic cells have a common anterior/posterior (a/p) polarity that is apparent in the localization of the transcription factor POP-1 [1, 2]. The level of nuclear POP-1 remains high in the anterior daughters of dividing cells but is lowered in the posterior daughters [2, 3]. To generate POP-1 asymmetry, most early embryonic cells require contact with signaling cells that express the ligand MOM-2/Wnt [4, 5]; the point of cell contact specifies the daughter with low nuclear POP-1 [6, 7]. In contrast, slightly older embryonic cells that have no apparent prior exposure to Wnt signaling can generate POP-1 asymmetry, provided these cells express MOM-5/Frizzled [7]. We show here that MOM-5::GFP is enriched at the posterior pole of cells prior to division and that a similar asymmetry is observed in cultured cells with no apparent prior exposure to Wnt signaling. While depleting these latter cells of MOM-5/Frizzled causes both daughter cells to have high levels of POP-1 [7], we show that both daughter cells have low levels of POP-1 in embryos with atypically high levels of MOM-5::GFP. These results suggest that MOM-5/Frizzled asymmetry leads to POP-1 asymmetry. In later embryogenesis, we find that MOM-5::GFP localizes to the leading edges of epidermal cells during ventral enclosure. These localization patterns suggest a parallel between MOM-5/Frizzled and the roles of Drosophila Frizzled in planar polarity and dorsal enclosure.