Embryonic asymmetry and development of functional neuronal connectivity

Embryonic cell division was observed in both Wild type (N₂) and del.gpa-16 C. elegans. N₂ worms presented 100% normal embryonic cell division. While the absence of del.gpa-16 , resulted in 50% normal embryonic cell division, over 30% divided abnormally. All N₂ adult worms were dextral and 30% of the del.gpa-16 mutants had reversed gut and gonad placement. Both strains of del.gpa-16 were abnormal in non-associative learning specifically, habituation. Compared to N_2, del.gpa-16 required more touches to habituate (40). del.gpa-16 mutants are defective in associative learning. Isoamyl alcohol was used to condition the worms in the absence of food. When transferred to test plates, N₂ worms avoided the isoamyl alcohol while del.gpa-16 mutants maintained their attraction (n=7). Connectivity of sensory neuron ASEr with interneuron AIY was observed. Wild type animals show stereotypic ASEr location while some of the del.gpa-16 animals showed reversed ASEr neuron location.