Sex-specific evolution of a Drosophila sensory system via interacting cis- and trans-regulatory changes

The evolution of gene expression via cis-regulatory changes is well established as a major driver of phenotypic evolution. However, relatively little is known about the influence of enhancer architecture and intergenic interactions on regulatory evolution. We address this question by examining chemosensory system evolution in Drosophila. D. prolongata males show a massively increased number of chemosensory bristles compared to females and males of sibling species. This increase is driven by sex-specific transformation of ancestrally mechanosensory organs. Consistent with this phenotype, the Pox neuro transcription factor (Poxn), which specifies chemosensory bristle identity, shows expanded expression in D. prolongata males. Poxn expression is controlled by non-additive interactions among widely dispersed enhancers. Although some D. prolongata Poxn enhancers show increased activity, the additive component of this increase is slight, suggesting most changes in Poxn expression are due to epistatic interactions between Poxn enhancers and trans-regulatory factors. Indeed, the expansion of D. prolongata Poxn enhancer activity is only observed in cells that express doublesex (dsx), the gene that controls sexual differentiation in Drosophila and also shows increased expression in D. prolongata males due to cis-regulatory changes. Although expanded dsx expression may contribute to increased activity of D. prolongata Poxn enhancers, this interaction is not sufficient to explain the full expansion of Poxn expression, suggesting that cis-trans interactions between Poxn, dsx, and additional unknown genes are necessary to produce the derived D. prolongata phenotype. Overall, our results demonstrate the importance of epistatic gene interactions for evolution, particularly when pivotal genes have complex regulatory architecture.

Human Olfaction

Olfaction, or sense of smell, is one of the many sensory/perceptual systems that humans use to process external stimuli. Human olfaction is relatively understudied. More literature has focused on olfaction in animals for which olfaction plays a larger role in critical functioning and survival. This bibliography provides key resources for information about human olfaction and then outlines twelve general topics that are of considerable value to understanding this primary sensory system. It begins by providing some general resources that outline the functions of olfaction in humans. Next, it explores the anatomy and physiology of the human olfactory system, recognizing that our understanding has been largely guided by studying animals. It addresses several important theories of human olfaction, including ones that have attempted to understand the initial receptor-level processing of stimuli and ones that have been developed to explain the whole system. After considering some historical issues in studying olfaction, it outlines the various ways that human olfaction is studied. It considers some issues in olfaction that are related to cognitive processes, such as language and memory. A critical topic in the chemical senses of smell and taste that is somewhat less relevant in other sensory systems is that of hedonics (pleasure or liking). This bibliography explores sex differences, which, though small, seem to be more prevalent than in other sensory systems. In addition, this bibliography explores the effect of age on olfaction, both in terms of the development of olfaction in children and the decline of olfaction in aging. The entry ends with clinical implications, primarily of smell loss. In light of the Covid-19 pandemic, which brought newfound appreciation for the importance of sense of smell in human experience, a summary of the effect of Covid-19 on human sense of smell is included. In this bibliography pioneering studies are emphasized, although reviews are included in cases where the literature is too extensive to be summed up by single studies.

Difficulties of the tactile sensory system sensory integration of children with autism

Sensory integration represents the organization of the senses for their use. It is a neuro-biological activity that allows the reception and processing of sensory information, which in arrive from the senses in huge quantities into the brain, at any time. The ability of the brain to successfully process tactile information allows the child to feel safe and develop a connection with those around it. An autistic child is not able to register many stimuli from their environment, so insufficient or poor sensory processing can contribute to the image of autism. Children with autism spectrum difficulties have specific difficulties in touch perception. The aim of the study was to examine the prevalence of sensory integration difficulties of the tactile sensory system of children with autism spectrum disorders, and to establish the statistical significance of differences in relation to children without developmental difficulties. The total sample of subjects (N=30) consisted of two subsamples. The first subsample of subjects (N=15) consisted of children with difficulties from the autism spectrum, and the second subsample of subjects (N=15) consisted of children without developmental difficulties. The measurement instrument was the „Questionnaire for testing tactile sensory sensitivity“ with 11 variables and the offered answers of possible sensory response was applied. The Mann-Whitney U test and the Wilcoxon W test at the level of statistical significance of p<0.05 were used to examine the statistical significance of the differences between the subsamples of the subjects. The results of the study showed that 86.67 % of children with autism have difficulties in sensory integration of the tactile sensory system. The hypersensitive type of sensory response has 26.67 %, and the hyposensitive sensory response 20 % of children with autism. 40.00 % of children with autism have a mixed type of tactile sensory. There is a statistically significant difference between children with autism and children without developmental difficulties on 4 variables.

Disrupted Association of Sensory Neurons With Enveloping Satellite Glial Cells in Fragile X Mouse Model

Among most prevalent deficits in individuals with Fragile X syndrome (FXS) is hypersensitivity to sensory stimuli and somatosensory alterations. Whether dysfunction in peripheral sensory system contributes to these deficits remains poorly understood. Satellite glial cells (SGCs), which envelop sensory neuron soma, play critical roles in regulating neuronal function and excitability. The potential contributions of SGCs to sensory deficits in FXS remain unexplored. Here we found major structural defects in sensory neuron-SGC association in the dorsal root ganglia (DRG), manifested by aberrant covering of the neuron and gaps between SGCs and the neuron along their contact surface. Single-cell RNAseq analyses demonstrated transcriptional changes in both neurons and SGCs, indicative of defects in neuronal maturation and altered SGC vesicular secretion. We validated these changes using fluorescence microscopy, qPCR, and high-resolution transmission electron microscopy (TEM) in combination with computational analyses using deep learning networks. These results revealed a disrupted neuron-glia association at the structural and functional levels. Given the well-established role for SGCs in regulating sensory neuron function, altered neuron-glia association may contribute to sensory deficits in FXS.

Shape Sensing of Hyper-Redundant Robots Using an AHRS IMU Sensor Network

The paper proposes a novel approach for shape sensing of hyper-redundant robots based on an AHRS IMU sensor network embedded into the structure of the robot. The proposed approach uses the data from the sensor network to directly calculate the kinematic parameters of the robot in modules operational space reducing thus the computational time and facilitating implementation of advanced real-time feedback system for shape sensing. In the paper the method is applied for shape sensing and pose estimation of an articulated joint-based hyper-redundant robot with identical 2-DoF modules serially connected. Using a testing method based on HIL techniques the authors validate the computed kinematic model and the computed shape of the robot prototype. A second testing method is used to validate the end effector pose using an external sensory system. The experimental results obtained demonstrate the feasibility of using this type of sensor network and the effectiveness of the proposed shape sensing approach for hyper-redundant robots.

Estrogens regulate early embryonic development of the olfactory sensory system via estrogen-responsive glia

ABSTRACT Estrogens are well-known to regulate development of sexual dimorphism of the brain; however, their role in embryonic brain development prior to sex-differentiation is unclear. Using estrogen biosensor zebrafish models, we found that estrogen activity in the embryonic brain occurs from early neurogenesis specifically in a type of glia in the olfactory bulb (OB), which we name estrogen-responsive olfactory bulb (EROB) cells. In response to estrogen, EROB cells overlay the outermost layer of the OB and interact tightly with olfactory sensory neurons at the olfactory glomeruli. Inhibiting estrogen activity using an estrogen receptor antagonist, ICI182,780 (ICI), and/or EROB cell ablation impedes olfactory glomerular development, including the topological organisation of olfactory glomeruli and inhibitory synaptogenesis in the OB. Furthermore, activation of estrogen signalling inhibits both intrinsic and olfaction-dependent neuronal activity in the OB, whereas ICI or EROB cell ablation results in the opposite effect on neuronal excitability. Altering the estrogen signalling disrupts olfaction-mediated behaviour in later larval stage. We propose that estrogens act on glia to regulate development of OB circuits, thereby modulating the local excitability in the OB and olfaction-mediated behaviour.

An Instrumented Assessment of Cerebral Palsy: A Systematic Review

Cerebral palsy is a neurological problem which mainly affects the children and is a frequent reason of physical inability. It affects both motor as well as sensory system. Due to physical disability quality treatment is required for CP children. For an effective treatment proper assessment and selection of correct assessment tool is necessary. This review was aimed to recognize the various assessment scales which are available to assess different domains in person of cerebral palsy patient along with their psychometric properties. We had done a review of literature through Cochrane library, Ovid MEDLINE and GOOGLE SCHOLAR, CINAHL till March 2020. The studies in English‐language related to the assessment scales for the cerebral palsy were reviewed. Many scales were evaluated for different symptoms and good psychometric properties in CP child. We reviewed many research and review article related to assessment for CP. Various titles, abstracts, and references were checked for the relevancy.eview was done for the assessment of alteration in muscle tone, impaired voluntary movement, pain, gross motor function, balance, cognition and gait. Cerebral palsy was the primary goal of findings in 198 studies. Out of these, 58 studies were not proved the definition of cerebral palsy. 96 studies reported assessment of cerebral palsy for different domain, 25 studies used etiology and incidence and 19 studies for other domain which are related to CP. Many cerebral palsy scales are available, but only a very small number of scales were thoroughly validated for use in clinical practice in India. This review will help therapist in selection of appropriate tool and study of various symptoms in CP child before starting the treatment.

The role of intraspinal sensory neurons in the control of quadrupedal locomotion

From swimming to walking and flying, animals have evolved specific locomotor strategies to thrive in different habitats. All types of locomotion depend on integration of motor commands and sensory information to generate precise movements. Cerebrospinal fluid-contacting neurons (CSF-cN) constitute a vertebrate sensory system that monitors CSF composition and flow. In fish, CSF-cN modulate swimming activity in response to changes in pH and bending of the spinal cord, yet their role in higher vertebrates remains unknown. We used mouse genetics to study their function in quadrupedal locomotion and found that CSF-cN are directly integrated into spinal motor circuits by forming connections with motor neurons and premotor interneurons. Elimination of CSF-cN selectively perturbs the accuracy of foot placement required for skilled movements at the balance beam and horizontal ladder. These results identify an important role for mouse CSF-cN in adaptive motor control and indicate that this sensory system evolved a novel function from lower vertebrates to accommodate the biomechanical requirements of terrestrial locomotion.

Constitutivity in Flavour Perception

Within contemporary philosophy of perception, it is commonly claimed that flavour experiences are paradigmatic examples of multimodal perceptual experiences. In fact, virtually any sensory system, including vision and audition, is believed to influence how we experience flavours. However, there is a strong intuition, often expressed in these works, that not all of these sensory systems make an equal contribution to the phenomenology of flavour experiences. More specifically, it seems that the activities of some sensory systems are constitutive for flavour perception while others merely influence how we experience flavours. This paper aims to answer the question regarding the constitutive factors of flavour perception in a twofold way. First, a theoretical framework is developed, relying on debates regarding constitutivity in analytic metaphysics and philosophy of science, which defines the stronger and weaker senses in which the activities of sensory systems may be constitutive for flavour perception. Second, relying on empirical results in flavour science, the constitutive status of activities related to distinct sensory systems in the context of flavour perception is investigated.

Ultrastructure of the Sensilla on the Antennae and Mouthparts of Bean Weevils, Megabruchidius dorsalis (Coleoptera: Bruchinae)

Megabruchidius dorsalis (Fåhraeus, 1839) (Coleoptera: Bruchinae) is an important pest that damages the seeds of Gleditsia L. (Fabaceae: Caesalpinioideae). This beetle searches for host plants with its sensory system. To further explore the mechanisms of host location and to understand the ultrastructure of M. dorsalis, we examined the morphology and distribution of its sensilla on the antennae and mouthparts of male and female adults, using scanning electron microscopy (SEM). Both male and female antennae are serrated and can be divided into scape, pedicel, and flagellum. There were seven types and eight subtypes of antennal sensilla, including Bőhm bristles (BB), two subtypes of sensilla trichoid (ST1, ST2), two subtypes of sensilla chaetica (SC1, SC2), four subtypes of sensilla basiconic (SB1, SB2, SB3, SB4), sensilla cavity (SCa), sensilla auricillica (SA), and sensilla gemmiformium (SG). Five types of maxillary and labial palp sensilla in the mouthparts were observed: sensilla chaetica (SC), sensilla trichoidea (ST), sensilla styloconica (SSt), sensilla coeloconica (SCo), and sensilla digitiform (SD). No sexual dimorphism in sensilla type was observed, but there were variations between males and females in the numbers and distribution along the antennae. There were more SA in males than in females, while the number of ST sensilla in the maxillary palps were lower in males than in females. ST1 were most abundant in both sexes. We discussed potential function related to structure via comparisons with previous investigations of bruchids and other insects. Our results provide a theoretical basis for further studies on sensory physiological function, using semiochemicals as effective biological controls of M. dorsalis.