INVESTIGATING THE EFFECTS OF GLUCOSE, GLUTAMINE, AND 5-FLUORODEOXYURIDINE (FUDR) ON CILIA LENGTH AND INTRAFLAGELLAR TRANSPORT DYNAMICS IN Caenorhabditis elegans

Abstract

Cilia are sensory cellular organelles essential for development, signaling, and homeostasis, with dysfunction leading to a broad spectrum of diseases collectively termed ciliopathies. Intraflagellar transport (IFT), a bidirectional process critical for cilia assembly and maintenance, is regulated by kinesin and dynein motors and influenced by metabolic states. This study aimed to examine the effects of 5-fluorodeoxyuridine (FUDR), glucose, and glutamine on ciliogenesis, including ciliary length and IFT dynamics in the sensory neurons in Caenorhabditis elegans. C. elegans were treated with glucose, glutamine, or FUDR. Morphological changes in cilia were investigated using fluorescence microscopy, and IFT dynamics, including localization, IFT particle frequency, and IFT speed, were measured in worms through time-lapse imaging of fluorescently labeled IFT proteins in PHA/PHB neurons. Quantitative analyses were conducted for all treatment groups. Glucose significantly shortened cilia and altered IFT, including mid-ciliary accumulation and a slight reduction in anterograde IFT frequency. On the other hand, glutamine treatment only increased cilia length but did not interfere with IFT, whereas FUDR had little effect on both. Our results highlight the role of nutrient availability as a factor responsible for the modulation of cilia length and IFT dynamics.

Keywords

• Sensory Cilia
• Glucose
• Glutamine
• 5-Fluorodeoxyuridine (FUDR)
• C. elegans

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