A functional genomic analysis of cell morphology using RNA interference.

Area of Science:

• Cell Biology
• Genetics
• Developmental Biology

Background:

• Metazoan cell shape diversity is regulated by the dynamic cytoskeletal network.
• RNA-interference (RNAi) technology enables systematic screening for genes controlling cell morphology.

Purpose of the Study:

• To perform a comprehensive genetic dissection of cell morphogenesis using high-throughput RNAi screening.
• To identify genes responsible for the characteristic shapes of two distinct Drosophila cell lines.

Main Methods:

• Adapted RNAi technology for high-throughput screening in Drosophila cell culture.
• Conducted RNAi screens targeting 994 predicted cell shape regulators in two distinct cell lines.
• Utilized automated fluorescence microscopy to analyze actin filaments, microtubules, and DNA, identifying morphological phenotypes.

Main Results:

• Detected morphological phenotypes for 160 genes, with one-third being previously uncharacterized in vivo.
• Identified known cytoskeletal pathway components and proposed functions for novel genes based on shared phenotypes.
• Uncovered pathway-specific genes using co-RNAi screening to identify suppressors of Pten dsRNA-induced cell shape changes.

Conclusions:

• RNAi screening successfully identified genes influencing cytoskeletal organization and morphology in two distinct cell types.
• Some identified genes showed conserved functions across cell types, while others displayed cell-type-specific roles.
• Findings highlight the diverse mechanisms underlying cell shape generation, such as round versus flat morphologies.