Transport of CaM kinase along processes elicited by neuronal contact evokes an inhibition of arborization and outgrowth in D. melanogaster cultured neurons

Abstract

Transgenic Drosophila strains expressing an inhibitory peptide of Ca2+/calmodulin dependent protein kinase II (CaM kinase), or a constitutively activated CaM kinase, show altered neuronal process morphology compared to wild type in scanning electron microscopy (SEM) of cultured mature neurons from embryonic neuroblasts. We observed significantly enhanced process growth in cells with inhibited enzyme, and reduced process growth in cells with activated enzyme, suggesting that active CaM kinase is involved in the inhibition of neurite growth during development. The subcellular distribution of CaM kinase in wild type neuronal cultures was determined using a gold particle labeling procedure which allowed the mapping of the enzyme directly in the scanning electron microscope (SEM). Before neuronal contact there was little labeling of processes, but after connections had been made the processes were heavily labeled. Our results suggest that the major transport of CaM kinase to the terminals does not occur until after or during the formation of neuronal connections when a functional synapse might be formed. Taken together, these results suggest a target-dependent transport of the enzyme along processes and an inhibitory role for CaM kinase on neurite branching.

Cooperation between Drosophila flies in searching behavior

“…1993) (maximum ratio after 15 h: 5.05 ± 0.6 and 3 ± 0.35 for systems with and without denatonium, respectively, t = 2.64, P = 0.01, df = 18). On the other hand, RQED which expresses Cam kinase II under heat shock promoter (Broughton et al . 1996) showed a pattern not substantially different from C‐S (maximum ratio obtained for RQED with the denatonium system, 3.3 ± 0.15 vs. 2.7 ± 0.25 for C‐S ).…”

“…1987; Levin et al . 1992) is an adenyl cyclase mutant with a low level of cAMP, RQED (Broughton et al . 1996) over‐expresses Cam kinase II under heat shock promoter and ala 2 (Griffith et al .…”

“…Molecular genetic tools coupled with behavioral studies might help us to understand the mechanisms that underlie search/aggregation cycles. In this research mutants of neuronal signaling presenting altered kinase activities under control of calcium, cAMP and cGMP were used (Broughton et al 1996;Dudai et al 1976;Levin et al 1992;Osborne et al 1997). In addition, white eyed mutation was used, which is supposed to interfere with vision (although these mutants might have residual visual ability) (Green 1959).…”

Organization and evolution of multifunctional Ca2+/CaM-dependent protein kinase genes

“…Drosophila melanogaster has a single CaMK-II gene, from which at least five variants are expressed that are important in development and behavior (Griffith and Greenspan, 1993;Ohsako et al, 1993;Takamatsu et al, 1994;VanBerkum and Goodman, 1995;Broughton et al, 1996;VanBerkum, 1996;Kahn and Matsumoto, 1997;Koh et al, 1999;Beumer et al, 2002). The single CaMK-II gene in the nematode Caenorhabditis elegans (unc-43) has been implicated in diverse behavioral phenomena (Reiner et al, 1999;Troemel et al, 1999;Wang and Wadsworth, 2002).…”

Constitutive Activation of Ca2+/Calmodulin-Dependent Protein Kinase II during Development Impairs Central Cholinergic Transmission in a Circuit Underlying Escape Behavior inDrosophila

“…In vitro studies of Drosophila neurons revealed an inhibitory role of CaMKII on neurite branching (Broughton et al, 1996). In contrast, CaMKII expression in the dendritic arbors of sensory neurons increased the dynamic nature and formation of filopodia during development (Andersen et al, 2005).…”