In many mating systems female reproductive capacity is a limiting resource over which males will compete. As a consequence, males and females have usually different fitness optimization strategies which may give rise to sexual conflict. Since simultaneous hermaphrodites have, in theory, the option to mate as male or as female at any time, conflict will occur if partners insist in taking the sam...

Aerial respiratory behaviour in Lymnaea stagnalis was operantly conditioned using a procedure that results in long-term memory (LTM) persisting for 1 but not 3 days. By manipulating the snails' post-training environment, i.e. preventing Lymnaea from performing aerial respiratory behaviour, memory persistence was significantly extended. Memory retention, however, is only extended if snails are p...

Activation of phagocytic cells in the injury zone is a crucial step in the regeneration of peripheral axons. Many aspects of the mechanisms underlying the recruitment of active phagocytes remain, however, unclear. Notably, our understanding of the interactions between injury, extracellular matrix (ECM) degradation and phagocyte activation is limited. Most animal cell types, phagocytes included,...

Similar to other invertebrate and vertebrate animals, cAMP-dependent signaling cascades are key components of long-term memory (LTM) formation in the snail Lymnaea stagnalis, an established experimental model for studying evolutionarily conserved molecular mechanisms of long-term associative memory. Although a great deal is already known about the signaling cascades activated by cAMP, the molec...

Learning and memory formation are essential physiological functions. While quiescent neurons have long been the focus of investigations into the mechanisms of memory formation, there is increasing evidence that spontaneously active neurons also play key roles in this process and possess distinct rules of activity-dependent plasticity. In this study, we used a well-defined aversive learning mode...

It is well known that many bacteria can survive in a growth-arrested state for long periods of time, on the order of months or even years, without forming dormant structures like spores or cysts. How is such longevity possible? What is the molecular basis of such longevity? Here we used the Gram-negative phototrophic alphaproteobacterium Rhodopseudomonas palustris to identify molecular determin...

Coexistence of regulatory peptides is reported with increasing frequency in the mammalian neuroendocrine system. We have investigated the possible presence of such coexistence in the invertebrate Lymnaea stagnalis and have found evidence for concurrence of enkephalin- and gastrin/cholecystokinin (CCK)-like peptides in identified neurosecretory neurons. Our immunocytochemical studies reveal, how...