Spencer Allison K, Siddiqui Bilal A, Thomas Jeffrey H
Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, 3601 4th Street, STOP 6540, Lubbock, TX 79430, United States.
Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, 3601 4th Street, STOP 6540, Lubbock, TX 79430, United States.
Dev Biol. 2015 Jun 15;402(2):192-207. doi: 10.1016/j.ydbio.2015.03.022. Epub 2015 Apr 28.
Invagination of epithelial sheets to form furrows is a fundamental morphogenetic movement and is found in a variety of developmental events including gastrulation and vertebrate neural tube formation. The cephalic furrow is a deep epithelial invagination that forms during Drosophila gastrulation. In the first phase of cephalic furrow formation, the initiator cells that will lead invagination undergo apicobasal shortening and apical constriction in the absence of epithelial invagination. In the second phase of cephalic furrow formation, the epithelium starts to invaginate, accompanied by both basal expansion and continued apicobasal shortening of the initiator cells. The cells adjacent to the initiator cells also adopt wedge shapes, but only after invagination is well underway. Myosin II does not appear to drive apical constriction in cephalic furrow formation. However, cortical F-actin is increased in the apices of the initiator cells and in invaginating cells during both phases of cephalic furrow formation. These findings suggest that a novel mechanism for epithelial invagination is involved in cephalic furrow formation.
上皮细胞层内陷形成沟是一种基本的形态发生运动，见于多种发育事件，包括原肠胚形成和脊椎动物神经管形成。头部沟是果蝇原肠胚形成期间形成的一种深陷的上皮内陷。在头部沟形成的第一阶段，将引领内陷的起始细胞在没有上皮内陷的情况下经历顶-基缩短和顶端收缩。在头部沟形成的第二阶段，上皮开始内陷，同时伴随着起始细胞的基部扩张和持续的顶-基缩短。与起始细胞相邻的细胞也呈楔形，但仅在内陷充分进行之后。肌球蛋白II似乎并不驱动头部沟形成过程中的顶端收缩。然而，在头部沟形成的两个阶段中，起始细胞顶端和内陷细胞中的皮质F-肌动蛋白均增加。这些发现表明，一种新的上皮内陷机制参与了头部沟的形成。
