High DAG content until memory acquisition and low DAG content after the acquisition leads to promote forgetting. A, B, The chemotaxis of naive, adapted, and 4 h recovery of PMA administered WT animals (A) and tir-1 mutant (B) was analyzed. –, exposed only solvent (ethanol as control); PMA, exposed PMA dissolved in ethanol. For example, PMA→PMA→ −, exposed to PMA dissolved in ethanol during cultivation and adaptation, and to ethanol during 4 h recovery. A, The chemotaxis of WT animals after recovery was not affected by PMA exposure during cultivation, during adaptation, and/or during recovery, individually. In addition, PMA exposure during cultivation made WT difficult to adapt to diacetyl. Asterisks indicate significant differences between after adaptation and after 4 h recovery or between after adaptation of two conditions. Adaptation versus recovery in − → − → −: p = 9.94 × 10−20; PMA → − → −: p = 7.40 × 10−5; − → PMA → −: p = 5.44 × 10−18; − → − → PMA: p = 1.56 × 10−17; − → PMA → PMA: p = 3.52 × 10−12; and adaptation in − → − → − versus PMA → − → −: p = 1.43 × 10−8; PMA → − → − versus − → PMA → −: p = 7.13 × 10−7 (n = 8, F(8,105) = 6.13, p = 1.81 × 10−6). B, tir-1 mutant exposed PMA during cultivation or during adaptation rose the chemotaxis of after recovery. However, PMA exposure during recovery canceled the effect. PMA exposure during cultivation reduced the naive chemotaxis of tir-1 and made it difficult to adapt to diacetyl. Asterisks indicate significant differences between naive, after adaptation, or after 4 h recovery of two conditions. Recovery in − → − → − versus PMA → − → −: p = 0.00281; − → − → − versus − → PMA → −: p = 2.77 × 10−5; − → PMA → − versus − → PMA → PMA: p = 2.18 × 10−6; naive in − → − → − versus PMA → − → −: p = 0.000633; adaptation in − → − → − versus PMA → − → −: p = 1.30 × 10−5; PMA → − → − versus − → PMA → −: p = 0.000217 (n = 8, F(8,105) = 13.10, p = 5.91 × 10−13). C, Representative expression of DownwardDAG2 (Green) with DiI (Red) staining pattern in WT. DownwardDAG2 expressed in AWC neurons. Scale bar, 10 μm. D, Fluorescent intensity of DownwardDAG2 was measured in AWC sensory neurons of WT and mutants at naive, after adaptation, and after recovery. Asterisks indicate significant differences between strains in naive, after adaptation, or after 4 h recovery. In naive, WT versus tir-1: p = 0.00711 (n = 66, 63, 80, 65, F(3,270) = 4.03, p = 0.00787). In adaptation, WT versus tir-1: p = 0.00946; WT versus goa-1;tir-1: p = 0.00360; tir-1 versus goa-1: p = 0.0315; goa-1 versus goa-1;tir-1: p = 0.0129 (n = 49, 44, 68, 53, F(3,210) = 6.55, p = 0.000297). In recovery, WT versus tir-1: p = 2.68 × 10−5; tir-1 versus goa-1: p = 4.38 × 10−5 (n = 64, 56, 74, 45, F(3,235) = 9.82, p = 3.97 × 10−6). Box plots: center line indicates median. Box range, 25th-75th percentiles. Whiskers represent minimum-maximum values. Dots represent the data points. External dots from whisker represent outliers. *p < 0.05; **p < 0.01; ***p < 0.001; two-way ANOVA with Bonferroni correction (A,B) or one-way ANOVA with Tukey–Kramer multiple test (D).
