Journal of neurogenetics最新文献

Animals use an array of visual cues to gauge distance, and their underlying neural mechanisms remain largely unknown. Zebrafish larvae execute different hunting behaviors depending on distance to the prey, providing a simple model system in which to study this process. To identify distance cues, we presented equivalent prey stimuli at increasing distance and recorded hunting behaviors. We found that the initial convergence angle was lower for more distant prey, suggesting that they are able to gauge distance to the prey via monocular cues. We investigated blur as a possible monocular cue, and found that by artificially blurring the stimulus, we were able to reduce initial convergence and strike probability. This implicates blur as a distance cue in zebrafish prey capture, adds to our knowledge of how larvae are able to visually target and accurately capture prey.

The swift updates of public databases and advancements in next-generation sequencing (NGS) technologies have enhanced the genetic identification capacities of epilepsy clinics. This study aimed to evaluate the diagnostic efficacy of NGS in pediatric epilepsy patients as a whole and to present the data obtained in the whole exome sequence analysis. We enrolled 40 children with suspected childhood epilepsy in this study. All patients underwent evaluation by a clinical geneticist or pediatric neurologist and the molecular genetic analysis of those children was performed by whole-exome sequencing (WES). Out of the 40 patients, 12 (30%) received a genetic diagnosis, involving 14 mutations across 13 genes. The cumulative positive diagnostic yield was 30%. Twelve of these patients were identified to have 5 variants previously documented as pathogenic, 9 variants classified as likely pathogenic, and 5 novel variants that have not been reported before. The outcomes indicate that whole-exome sequencing offers great benefits in clinical patient diagnosis, particularly in terms of detecting diagnostic variants. This study underscored the significance of whole exome sequencing (WES) studies, where only a broad gene set is examined in epilepsy patients. This approach has the potential to establish gene-specific phenotypic profiles, particularly by uncovering novel candidate genes in epilepsy patients with well-defined phenotypes. Additionally, conducting validation studies on variants of uncertain clinical significance could enhance the outcome yield.

The study of olfaction in Drosophila melanogaster has greatly benefited from genetic reagents such as olfactory receptor mutant lines and GAL4 reporter lines. The CRISPR/Cas9 gene-editing system has been increasingly used to create null receptor mutants or replace coding regions with GAL4 reporters. To further expand this toolkit for manipulating fly olfactory receptor neurons (ORNs), we generated null alleles for 11 different olfactory receptors by using CRISPR/Cas9 to knock in LexA drivers, including multiple lines for receptors which have thus far lacked knock-in mutants. The targeted neuronal types represent a broad range of antennal ORNs from all four morphological sensillum classes. Additionally, we confirmed their loss-of-function phenotypes, assessed receptor haploinsufficiency, and evaluated the specificity of the LexA knock-in drivers. These receptor mutant lines have been deposited at the Bloomington Drosophila Stock Center for use by the broader scientific community.

Egg-laying is one of the key aspects of female reproductive behavior in insects. Egg-laying has been studied since the dawn of Drosophila melanogaster as a model organism. The female's internal state, hormones, and external factors, such as nutrition, light, and social environment, affect egg-laying output. However, only recently, neurobiological features of egg-laying behavior have been studied in detail. fruitless and doublesex, two key players in the sex determination pathway, have become focal points in identifying neurons of reproductive significance in both central and peripheral nervous systems. The reproductive tract and external terminalia house sensory neurons that carry the sensory information of egg maturation, mating and egg-laying. These sensory signals include the presence of male accessory gland products and mechanical stimuli. The abdominal neuromere houses neurons that receive information from the reproductive tract, including sex peptide abdominal ganglion neurons (SAGs), and send their information to the brain. In the brain, neuronal groups like aDNs and pC1 clusters modulate egg-laying decision-making, and other neurons like oviINs and oviDNs are necessary for egg-laying itself. Lastly, motor neurons involved in egg-laying, which are mostly octopaminergic, reside in the abdominal neuromere and orchestrate the muscle movements required for laying the egg. Egg-laying neuronal control is important in various evolutionary processes like cryptic female choice, and using different Drosophila species can provide intriguing avenues for the future of the field.