STUDY OF MITOTIC-ACTIVITY OF HEAD GANGLIO N-CELLS OF DROSOPHILA-MELANOGASTER LARVAE FROM TS-MUTANT STOCK WITH MODIFIED CAPACITY FOR LEARNING AND AUGMENTED ACTIVATOR POTENTIALITIES OF CALMODULIN

Mitotic activity of head neural ganglion cells, of Drosophila melanoga ster larvae from two genetic stocks was studied. The mutant stock agts 3 with augmented activatory potentialities of calmodulin and modified capacity for learning was compared with the control wild type Canton-S stock. The mitotic index was defined as the ratio of the number of ce lls in the state of division to the total cell number. The mitotic ind ex was calculated after 30-min incubation of the larvae at the tempera ture of 37 degrees C and without heating under normal conditions (22 d egrees C). At 22 degrees C the mitotic index in agts3 was higher than in CS. Exposure to 37 degrees C led to a sharp decrease of mitotic act ivity in both stocks. Increased mitotic index in agts 3 stock at 22 de grees C was probably connected with augmented activatory potentialitie s of calmodulin. After preincubation of the neural ganglions with calm odulin inhibitor;trifluoperazine (10(-3) M) for 30 minutes the differe nce between the mutant and control stocks in mitotic index disappeared due to its approximately 3-fold decrease in agts3 stock. The obtained results supported the proposed hypothesis and demonstrated importance of calmodulin as a regulator of mitotic activity of cells from the ne ural ganglion of Drosophila larvae.