Expressional artifact caused by a co-injection marker rol-6 in C. elegans

Area of Science:

• Molecular Biology
• Neuroscience
• Genetics

Background:

• Selection markers are crucial for generating transgenic animals.
• The rol-6 co-injection marker is widely used in C. elegans for its roller phenotype, but potential off-target effects were unknown.

Purpose of the Study:

• To investigate potential unintended effects of the rol-6 co-injection marker on gene expression in transgenic C. elegans.
• To identify the source of observed aberrant gene expression.

Main Methods:

• Transgenic C. elegans lines were generated using the rol-6 co-injection marker.
• Expression patterns of a test gene (GFP) were analyzed, particularly in male-specific neurons.
• The rol-6 gene sequence was investigated as the cause of observed expression patterns.

Main Results:

• The rol-6 co-injection marker caused specific expression of GFP in the male-specific interneuron CP09.
• The rol-6 gene sequence within the marker plasmid was identified as responsible for this unintended expression.
• This effect was specific to male C. elegans.

Conclusions:

• The rol-6 co-injection marker is not recommended for precise expression or functional studies targeting male C. elegans neurons due to potential confounding expression.
• The identified rol-6 sequence offers potential for targeted expression in the CP09 neuron for future research.