The bicistronic gene würmchen encodes two essential components for epithelial development in Drosophila

Area of Science:

• Cell Biology
• Developmental Biology
• Genetics

Background:

• Epithelial tissues form body compartments and maintain tissue integrity through apical extracellular matrix secretion and barrier functions.
• Barrier function is mediated by tight junctions in vertebrates and septate junctions in invertebrates.
• The genetic basis for septate junction formation and epithelial development is not fully understood.

Purpose of the Study:

• To investigate the function of the bicistronic gene würmchen in epithelial tissue development.
• To identify the roles of the polypeptides Würmchen1 and Würmchen2 in epithelial tissue organization and function.

Main Methods:

• CRISPR/Cas9 gene editing was used to create mutations in the würmchen gene.
• Immunolocalization and phenotypic analysis were employed to study the effects of mutations on epithelial tissues.
• Functional assays were conducted to assess barrier function and cellular transport.

Main Results:

• The bicistronic gene würmchen encodes two essential polypeptides: Würmchen1 and Würmchen2.
• Würmchen1 is a core component of septate junctions, essential for their organization, transepithelial barrier function, cellular transport, and tracheal system morphogenesis during embryogenesis.
• Würmchen2 localizes to the apical membrane and tracheal lumen and is essential for later larval development.

Conclusions:

• Würmchen1 is a novel and essential component of septate junctions, critical for epithelial integrity and development.
• The würmchen gene and its encoded proteins play fundamental roles in epithelial tissue organization and function from embryogenesis through larval stages.