A cellular tilting mechanism important for dynamic tissue shape changes and cell differentiation in Drosophila

Area of Science:

• Developmental biology
• Cell biology
• Tissue morphogenesis

Background:

• Dynamic changes in three-dimensional cell shape are essential for tissue development and function.
• The morphogenetic furrow (MF) in the developing Drosophila eye involves epithelial folding and cell shape changes during photoreceptor differentiation.

Purpose of the Study:

• To investigate the cellular mechanisms underlying morphogenetic furrow progression.
• To identify the role of cell movement and protrusion formation in tissue shape dynamics and differentiation.

Main Methods:

• Observing cell behaviors during morphogenetic furrow progression in Drosophila.
• Analyzing cell edge movements (apical vs. basal).
• Investigating the role of Src42A and Rac1 in protrusion formation using knockdown and photoactivation techniques.

Main Results:

• Cells within the morphogenetic furrow exhibit a tilting movement, with basal edges moving in opposition to apical edges.
• Oriented, force-generating protrusions are generated at the basal side of cells.
• Reduced protrusion formation, due to Src42A knockdown or Rac1 inhibition, impairs basal cell movement.
• Impaired basal cell movement leads to slowed morphogenetic furrow progression and photoreceptor differentiation.

Conclusions:

• A novel cellular tilting mechanism, involving basal protrusions, is identified as critical for morphogenetic furrow progression.
• This tilting mechanism plays a significant role in regulating tissue shape dynamics and facilitating cell differentiation during eye development.