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Neuropeptides are an important class of molecules involved in diverse aspects of metazoan development and homeostasis. Insects are ideal model systems to investigate neuropeptide functions, and the major focus of insect neuropeptide research in the last decade has been on the identification of their receptors. Despite these vigorous efforts, receptors for some key neuropeptides in insect development such as prothoracicotropic hormone, eclosion hormone and allatotropin (AT), remain undefined. In this paper, we report the comprehensive cloning of neuropeptide G protein-coupled receptors from the silkworm, Bombyx mori, and systematic analyses of their expression. Based on the expression patterns of orphan receptors, we identified the long-sought receptor for AT, which is thought to stimulate juvenile hormone biosynthesis in the corpora allata (CA). Surprisingly, however, the AT receptor was not highly expressed in the CA, but instead was predominantly transcribed in the corpora cardiaca (CC), an organ adjacent to the CA. Indeed, by using a reverse-physiological approach, we purified and characterized novel allatoregulatory peptides produced in AT receptor-expressing CC cells, which may indirectly mediate AT activity on the CA. All of the above findings confirm the effectiveness of a systematic analysis of the receptor transcriptome, not only in characterizing orphan receptors, but also in identifying novel players and hidden mechanisms in important biological processes. This work illustrates how using a combinatorial approach employing bioinformatic, molecular, biochemical and physiological methods can help solve recalcitrant problems in neuropeptide research.

Abstract Purpose To detect the epileptogenic region causing epileptic spasms in an infant with tuberous sclerosis (TS). Methods We applied a multiple band frequency analysis to video electroencephalographic (EEG) recordings of the infant’s scalp. We also performed computed tomography (CT), magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), and magnetoencephalography (MEG) of the brain in order to ascertain the epileptic focus. Results During the periodic spasms, we identified fast ictal activity with frequencies of 60–70 Hz in the right centroparietal region. This region was part of the area surrounding the largest cortical tuber that was identified on CT and MRI and was located in the right frontal lobe. An area of increased blood perfusion that was observed with SPECT and dipole sources that were determined with interictal MEG were also located in this area. In addition, ictal frequency oscillations (FOs) with high gamma activity were identified over the cortex surrounding the largest tuber. After a lesionectomy of this tuber, the periodic spasms disappeared, and no FOs were detected over this area. Conclusions Scalp EEG, which identified the ictal onset zone by detecting fast activity that was suggestive of FOs, was useful for detecting the epileptogenic region in an infant with TS.

A rosette‐forming glioneuronal tumor (RGNT) was initially reported as an infratentorial tumor that comprised both small neurocytic rosettes and astrocytic components. However, a few studies have reported supratentorial RGNTs arising in the cerebral hemispheres. Here, we report an unusual case involving a 9‐year‐old boy with a supratentorial RGNT who presented with intractable epilepsy and behavioral changes. Brain MRI revealed a well‐circumscribed space‐occupying lesion with septae in the right inferomedial parietal lobe. Electroencephalography showed multifocal spikes over the right frontal, temporal and parietal regions. The seizure frequency decreased dramatically after tumorectomy. Histopathological examination revealed prominent neurocytic rosette formation appearing with the specific glioneuronal element of a dysembryoplastic neuroepithelial tumor (DNT). Although the pathogenesis has not been elucidated, a supratentorial RGNT presenting with epilepsy may exhibit a rosette component, which is the major feature of this tumor, against the background of a specific glioneuronal element mimicking DNT. However, RGNT arising in regions other than the fourth ventricle is rare, and the pathogenesis of epilepsy due to RGNT has not been fully elucidated. Further clinical and histological studies are required to understand the pathology underlying epilepsy caused by RGNT. [ABSTRACT FROM AUTHOR]