Genes controlling cellular polarity in Drosophila

Area of Science:

• Developmental Biology
• Genetics
• Cell Biology

Background:

• Cellular polarity is a fundamental yet poorly understood aspect of biological development.
• Genes controlling embryonic polarity across three axes (apical-basal, proximodistal, dorsoventral) have been identified in Drosophila.
• Mutations affecting adult polarity in Drosophila lead to pattern alterations like rotations and mirror-image duplications.

Purpose of the Study:

• To investigate how cellular polarity is controlled in Drosophila development.
• To understand the mechanisms by which polarity influences cell fate and pattern formation in adult structures.
• To explore the relationship between cell differentiation and polarity signaling.

Main Methods:

• Analysis of mutations affecting polarity in Drosophila embryos and adult structures.
• Examination of imaginal discs and specific adult fields (tarsal segments, ommatidia, bristle sockets).
• Observation of pattern alterations, including rotations, mirror-image duplications, and changes in bristle/hair orientation.

Main Results:

• In regions with similar neighboring cells, imaginal polarity mutants alter bristle and hair orientation but not cell fate.
• Specific adult fields exhibit fine-scale mirror-image reversals and pattern duplications, similar to embryonic segment polarity mutants.
• Polarity control impacts cell orientation or fate based on cell differentiation relative to neighbors.

Conclusions:

• Cellular polarity's influence on cell fate versus orientation depends on cell differentiation status.
• The control of cellular polarity is intrinsically linked to internal cytoskeletal organization.
• Spatial organization of signal transduction molecules within the cell membrane is critical for cellular polarity.