Kuzmanov Aleksandra, Yochem John, Fay David S
Department of Molecular Biology, College of Agriculture and Natural Resources, University of Wyoming, Laramie, Wyoming 82071.
Department of Molecular Biology, College of Agriculture and Natural Resources, University of Wyoming, Laramie, Wyoming 82071
Genetics. 2014 Sep;198(1):259-68. doi: 10.1534/genetics.114.166876. Epub 2014 Jul 9.
PHA-1 encodes a cytoplasmic protein that is required for embryonic morphogenesis and attachment of the foregut (pharynx) to the mouth (buccal capsule). Previous reports have in some cases suggested that PHA-1 is essential for the differentiation of most or all pharyngeal cell types. By performing mosaic analysis with a recently acquired pha-1 null mutation (tm3671), we found that PHA-1 is not required within most or all pharyngeal cells for their proper specification, differentiation, or function. Rather, our evidence suggests that PHA-1 acts in the arcade or anterior epithelial cells of the pharynx to promote attachment of the pharynx to the future buccal capsule. In addition, PHA-1 appears to be required in the epidermis for embryonic morphogenesis, in the excretory system for osmoregulation, and in the somatic gonad for normal ovulation and fertility. PHA-1 activity is also required within at least a subset of intestinal cells for viability. To better understand the role of PHA-1 in the epidermis, we analyzed several apical junction markers in pha-1(tm3671) homozygous embryos. PHA-1 regulates the expression of several components of two apical junction complexes including AJM-1-DLG-1/discs large complex and the classical cadherin-catenin complex, which may account for the role of PHA-1 in embryonic morphogenesis.
PHA-1编码一种细胞质蛋白，该蛋白是胚胎形态发生以及前肠（咽）与口（颊囊）附着所必需的。先前的报道在某些情况下表明，PHA-1对大多数或所有咽细胞类型的分化至关重要。通过利用最近获得的pha-1无效突变（tm3671）进行镶嵌分析，我们发现大多数或所有咽细胞在其正常的特化、分化或功能过程中并不需要PHA-1。相反，我们的证据表明，PHA-1在咽的拱廊或前上皮细胞中起作用，以促进咽与未来颊囊的附着。此外，在胚胎形态发生过程中，表皮似乎需要PHA-1；在渗透调节过程中，排泄系统需要PHA-1；在正常排卵和生育过程中，体细胞性腺需要PHA-1。为了更好地理解PHA-1在表皮中的作用，我们分析了pha-1（tm3671）纯合胚胎中的几种顶端连接标记物。PHA-1调节两种顶端连接复合体的几个成分的表达，包括AJM-1-DLG-1/盘状大复合体和经典钙黏蛋白-连环蛋白复合体，这可能解释了PHA-1在胚胎形态发生中的作用。
