Structure and function of the moth mushroom body

The mushroom bodies are paired, high-order neuropils in the insect brain involved in complex functions such as learning and memory, sensory integration, context recognition and olfactory processing. This thesis explores the structure of the mushroom bodies in the noctuid moth Spodoptera littoralis using neuroanatomical staining methods, immunocytochemistry and electron microscopy, and investigates how the intrinsic neurons of the mushroom body, the Kenyon cells, respond to olfactory stimulation of the antennae using whole-cell patch clamp technique. The mushroom body in S. littoralis contains about 4,000 Kenyon cells, and consists of a calyx, pedunculus and two lobes, one medial and one vertical. The calyx houses dendritic branches of Kenyon cells and the pedunculus and lobes contain the axons and terminals of these neurons respectively. The calyx is doubled and concentrically divided into a broad peripheral zone, which receives input from antennal lobe projection neurons, and a narrow inner zone, which receives yet unidentified input. The lobes are parsed into three longitudinal divisions, which contain a separate subset of Kenyon cells each. The Kenyon cells are divided into three morphological classes, I-III. Class I Kenyon cells have widely branching spiny dendritic arborisations in both zones of the calyx and occupy the two most posterior subdivisions of the lobes called α/β and α´/β´. Class II Kenyon cells have narrow clawed dendritic trees in the calyx and invade the most anterior division in the lobes, called γ. Class III Kenyon cells have clawed, diffusely branching dendrites in the calyx and provide a separate system of axons and terminal branches, partly detached from the rest of the mushroom body, called the Y tract and lobelets. Kenyon cells within the classes display differential labeling with antisera against neuroactive substances. Kenyon cells make synaptic contact with one another and with other neuron types in the mushroom body. Extrinsic inhibitory and putative modulatory neurons were identified. Whole-cell patch clamp recordings revealed that Kenyon cells exhibit broadly tuned subthreshold activation by odor stimulation and a few cells responded with action potentials to specific biologically relevant odor combinations

A novel octopamine receptor with preferential expression in <i>Drosophila</i> mushroom bodies

Octopamine is a neuromodulator that mediates diverse physiological processes in invertebrates. In some insects, such as honeybees and fruit flies, octopamine has been shown to be a major stimulator of adenylyl cyclase and to function in associative learning. To identify an octopamine receptor mediating this function in Drosophila, putative biogenic amine receptors were cloned by a novel procedure using PCR and single-strand conformation polymorphism. One new receptor, octopamine receptor in mushroom bodies (OAMB), was identified as an octopamine receptor because human and Drosophila cell lines expressing OAMB showed increased cAMP and intracellular Ca2+ levels after octopamine application. Immunohistochemical analysis using an antibody made to the receptor revealed highly enriched expression in the mushroom body neuropil and the ellipsoid body of central complex, brain areas known to be crucial for olfactory learning and motor control, respectively. The preferential expression of OAMB in mushroom bodies and its capacity to produce cAMP accumulation suggest an important role in synaptic modulation underlying behavioral plasticity

Discrimination Training with Multimodal Stimuli Changes Activity in the Mushroom Body of the Hawkmoth Manduca sexta

The mushroom bodies of the insect brain play an important role in olfactory processing, associative learning and memory. The mushroom bodies show odor-specific spatial patterns of activity and are also influenced by visual stimuli.Functional imaging was used to investigate changes in the in vivo responses of the mushroom body of the hawkmoth Manduca sexta during multimodal discrimination training. A visual and an odour stimulus were presented either together or individually. Initially, mushroom body activation patterns were identical to the odour stimulus and the multimodal stimulus. After training, however, the mushroom body response to the rewarded multimodal stimulus was significantly lower than the response to the unrewarded unimodal odour stimulus, indicating that the coding of the stimuli had changed as a result of training. The opposite pattern was seen when only the unimodal odour stimulus was rewarded. In this case, the mushroom body was more strongly activated by the multimodal stimuli after training. When no stimuli were rewarded, the mushroom body activity decreased for both the multimodal and unimodal odour stimuli. There was no measurable response to the unimodal visual stimulus in any of the experiments. These results can be explained using a connectionist model where the mushroom body is assumed to be excited by olfactory stimulus components, and suppressed by multimodal configurations.Discrimination training with multimodal stimuli consisting of visual and odour cues leads to stimulus specific changes in the in vivo responses of the mushroom body of the hawkmoth

Dissecting the mechanisms of learning-by-doing in Drosophila

At the heart of learning-by-doing lies a well-known psychological phenomenon: information will be remembered better if it is actively generated rather than passively read or heard. First described in humans, this generation effect can also be observed in various animal models. However, the neurobiological mechanisms underlying the generation effect are unknown. Here we show that two reciprocal interactions between its active and passive components contribute to the generation effect in flies. One interaction consists of the active (skill-learning) component facilitating the passive (fact-learning) component. Fact-learning, on the other hand, inhibits skill-learning. Experiments with adenylyl cyclase I deficient _rutabaga_ mutant flies revealed that the fact- but not the skill-learning component requires this evolutionarily conserved learning gene. Using mushroom-body deficient transgenic flies we observed that the mushroom-bodies mediate the inhibition of skill-learning. This inhibition also enables generalization and prevents premature habit formation. Extended training in wildtype flies produced a phenocopy of mushroom-body impaired flies, such that generalization was abolished and goal-directed actions were transformed into habitual responses. Thus, our results identify various neural processes underlying learning-by-doing, delineate some of their synergisms and provide a framework for further dissecting them in a genetically tractable model system

Oilseed Rape straw for Cultivation of Oyster Mushroom

Oyster mushroom [_Pleurotus ostreatus_ var. _sajor caju_ (Fr.) Singer] cultivation can play an important role in managing organic waste. It can be cultivated on a wide rang of substrates containing lignin and cellulose. Oyster mushroom was grown on five substrates: Rise straw (Oryza sativa L. var. Alikazemi), Rise straw + Oilseed Rape straw (Brassica napus var. Hyola 401) (75:25 dw /dw), Rise straw + Oilseed Rape straw (50:50 dw /dw), Rise straw + Oilseed Rape straw (25:75 dw /dw) and Oilseed Rape straw alone. Oilseed Rape straw alone and Rise straw + Oilseed Rape straw (25:75 dw /dw) were best for fruit body production of P. ostreatus. Time to fruiting for P. ostreatus was also shorter on Oilseed Rape straw. Protein content of the fruit bodies obtained from Oilseed Rape straw was higher than those from other substrates. Using Oilseed Rape straw as a substrate appears to be suitable for oyster mushroom production

Pengaruh Penambahan Daun Pisang Kering (Klaras) dan Air Leri Terhadap Produktivitas Jamur Merang (Volvariella volvaceae) yang Ditanam Pada Baglog

Klaras is organic wastes dried banana leaves which has the main contentains in the form of hemicelluloses, so klaras expeted to be used as a planting medium merang mushroom. Leri water contains minerals, vitamin B1, B12 and nutrients which can be utilized as assitional nutrients to the growth of merang mushroom. The purpose of this study was to determine the effect of dried banana leaves and leri water on the productivity of merang mushroom grown on baglog. This study arranged in a completely randomized design (CRD) with two factors and thre replications. Factor 1 is klaras by weight: 125 grams (K1), 250 grams (K2), and 375 grams (K3). Factor 2 is leri water by volume: 50 ml (L1) and 100 ml (L2). Measured parameter is the fruit body weight and the amount of mushroom fruit body. Data were tested by analysis of variance 2 lanes. Based on analysis of variance showed that the addition of klaras media and water leri with different concentrations of influence on body weight and the amount of fruit merang mushroom edible merang mushroom fruit body. The best treatment for the body weight of fruit is K2L1 is 80,84 grams. While the lowes treatment is K0L1 is 61,67 grams. The best treatment for a number of fruiting bodies K2L1 is 6 pieces. While the lower treatment is K0L1 is 4 pieces

Specific requirement of NMDA receptors for long-term memory consolidation in Drosophila ellipsoid body

In humans and many other animals, memory consolidation occurs through multiple temporal phases and usually involves more than one neuroanatomical brain system. Genetic dissection of Pavlovian olfactory learning in Drosophila melanogaster has revealed multiple memory phases, but the predominant view holds that all memory phases occur in mushroom body neurons. Here, we demonstrate an acute requirement for NMDA receptors (NMDARs) outside of the mushroom body during long-term memory (LTM) consolidation. Targeted dsRNA-mediated silencing of Nmdar1 and Nmdar2 (also known as dNR1 or dNR2, respectively) in cholinergic R4m-subtype large-field neurons of the ellipsoid body specifically disrupted LTM consolidation, but not retrieval. Similar silencing of functional NMDARs in the mushroom body disrupted an earlier memory phase, leaving LTM intact. Our results clearly establish an anatomical site outside of the mushroom body involved with LTM consolidation, thus revealing both a distributed brain system subserving olfactory memory formation and the existence of a system-level memory consolidation in Drosophila

Pengaruh Penambah Eceng Gondok (Eichhornia crassipes) Dan Air Leri Terhadap Produksi Jamur Merang (Volvariella volvaceae) Pada Media BAGLOG

Water hyacinth is a weed plant, which contains such nutrients and cellulose, so the water hyacinth is expected to be used as a planting medium mushroom. Leri water contains minerals, vitamins B1, B12, and nutrients are utilized as additional nutrients for the growth of mushroom. The purpose of this study was to determine the effect of water hyacinth and water leri on productivity mushroom on baglog media. This research is compiled using a completely randomized design (CRD) with two factors and three replications. Factor 1 weight hyacinth: (E1) 125 grams, (E2) 250 grams, (E3) 375 grams. Factor 2 leri water volume (L1) and 50 ml (L2) of 100 ml. Parameters measured were body weight of the fruit and the number of mushroom fruit body. Data were tested by analysis of variance 2 lanes. Based on the analysis of variance showed that the addition of water hyacinth and water media leri with different concentrations of influence on the body weight of the fruit and the number of mushroom fruit body. The best treatment for the body weight of the fruit is E1L1 namely 76.67 grams, while the lowest was E3L1 treatment is 60 grams. The best treatment is E1L1 number of fruiting bodies is 7 pieces, while the lowest treatment E3L2 is 3 pieces