Mosquitoes transmit deadly pathogens from person to person as they obtain the blood meal that is essential for their life cycle. Female mosquitoes of many species are unable to reproduce without consuming protein that they obtain from blood. This developmental stage makes them highly efficient disease vectors of deadly pathogens. They can transmit pathogens between members of the same species and different species that can provide a route for evolving zoonotic viruses to jump from animals to humans. One possible way to develop novel strategies to combat pathogen transmission by mosquitoes is to study the sensory systems that drive mosquito reproductive behaviors, in particular the neural architecture and circuits of mosquito sensory afferent neurons, the central circuits that process sensory information, and the downstream circuits that drive reproductive behaviors. The study of mosquito neuroanatomy and circuitry also benefits basic neuroscience, allowing for comparative neuroanatomy in insect species, which has great value in the current model species-heavy landscape of neuroscience. Here, we introduce two important techniques that are used to study neuroanatomy and neural circuitry—namely, immunofluorescent labeling and neural tracing. We describe how to apply these approaches to study mosquito neuroanatomy and describe considerations for researchers using the techniques.

A researcher may have many reasons for wanting to establish new laboratory colonies from field-collected mosquitoes. In particular, the ability to study the diversity found within and among natural populations in a controlled laboratory environment opens up a wide range of possibilities for understanding how and why burdens of vector-borne disease vary over space and time. However, field-collected mosquitoes are often more difficult to work with than established laboratory strains, and considerable logistical challenges are involved in safely transporting field-collected mosquitoes into the laboratory. Here, we provide advice for researchers working with Aedes aegypti, Anopheles gambiae, and Culex pipiens, as well as notes on other closely related species. We provide guidance on each stage of the life cycle and highlight the life stages for which it is easiest to initiate new laboratory colonies for each species. In accompanying protocols, we provide methods detailing Ae. aegypti egg collection and hatching as well as how to transport larvae and pupae from the field.

Sleep is likely a whole-brain phenomenon, with most of the brain probably benefiting from this state of decreased arousal. Recent advances in our understanding of some potential sleep functions, such as metabolite clearance and synaptic homeostasis, make it evident why the whole brain is likely impacted by sleep: All neurons have synapses, and all neurons produce waste metabolites. Sleep experiments in the fly Drosophila melanogaster suggest that diverse sleep functions appear to be conserved across all animals. Studies of brain activity during sleep in humans typically involve multidimensional data sets, such as those acquired by electroencephalograms (EEGs) or functional magnetic resonance imaging (fMRI), and these whole-brain read-outs often reveal important qualities of different sleep stages, such as changes in frequency dynamics or connectivity. Recently, various techniques have been developed that allow for the recording of neural activity simultaneously across multiple regions of the fly brain. These whole-brain-recording approaches will be important for better understanding sleep physiology and function, as they provide a more comprehensive view of neural dynamics during sleep and wake in a relevant model system. Here, we present a brief summary of some of the findings derived from sleep activity recording studies in sleeping Drosophila flies and discuss the value of electrophysiological versus calcium imaging techniques. Although these involve very different preparations, they both highlight the value of multidimensional data for studying sleep in this model system, like the use of both EEG and fMRI in humans.

The establishment of neural connectivity is a major part of neural development. The central nervous system (CNS) midline is the most characterized axon guidance choice point, and work in Drosophila has played a pivotal role in understanding the molecular mechanisms responsible. Axons respond to attractive cues such as Netrin via the Frazzled receptor, and repulsive cues such as Slit via Robo receptors. Both signals are expressed at the CNS midline, affect pioneer axons, and have dramatic effects on the axon scaffold as a whole. Here, we focus on previous research analyzing classic mutants in the Slit/Robo pathway, which can readily be detected with a dissecting microscope. We also discuss analyzing these mutants in a teaching lab situation. The combination of sophisticated genetics and reliable axonal markers in Drosophila allows phenotypic analysis to be performed at the single-cell level. The elaborate architecture of neurons is very sensitive to disruption by genetic mutations, allowing the effects of novel mutations to be easily detected and assessed.

CRISPR–Cas9 has revolutionized gene editing for traditional and nontraditional model organisms alike. This tool has opened the door to new mechanistic studies of basic mosquito biology as well as the development of novel vector control strategies based on CRISPR–Cas9, including gene drives that spread genetic elements in the population. Although the promise of the specificity, flexibility, and ease of deployment CRISPR is real, its implementation still requires empirical optimization for each new species of interest, as well as to each genomic target within a given species. Here, we provide an overview of designing and testing single-guide RNAs for the use of CRISPR-based gene editing tools.

Analysis of taste sensory responses has been a powerful approach for understanding principles of taste detection and coding. The shared architecture of external taste sensing units, called sensilla, in insects opened up the study of tastant-evoked responses in any model of choice using a single-sensillum tip recording method that was developed in the mid-1900s. Early studies in blowflies were instrumental for identifying distinct taste neurons based on their responses to specific categories of chemicals. Broader system-wide analyses of whole organs have since been performed in the genetic model insect Drosophila melanogaster, revealing principles of stereotypical organization and function that appear to be evolutionarily conserved. Although limited in scope, investigations of taste sensory responses in mosquitoes showcase conservation in sensillar organization, as well as in groupings of functionally distinct taste neurons in each sensillum. The field is now poised for more thorough dissections of mosquito taste function, which should be of immense value in understanding close-range chemosensory interactions of mosquitoes with their hosts and environment. Here, we provide an introduction to the basic structure of a taste sensillum and functional analysis of the chemosensory neurons within it.

The host associations of mosquitoes vary by species, with some species being relative generalists, whereas others specialize, to varying extents, on a particular subset of the available host community. These host associations are driving factors in transmission dynamics of mosquito-vectored pathogens. For this reason, characterizing the host associations of mosquito species is critical for understanding the epidemiology of mosquito-vectored pathogens. Diverse methods have been used to associate mosquito species with their hosts. These typically include collecting mosquitoes that bite a restrained host (bait) or collecting wild blood-engorged mosquitoes and matching their blood meal to reference samples (blood meal analysis). Blood meal analysis refers to a collection of molecular techniques for determining the taxonomic identity of the source of a mosquito blood meal using cytological, serological, or DNA-based characteristics of the blood meal. Blood meal analyses that are based on DNA markers have advantages over cytological and serological methods and are effective for determining species-level identities of hosts from a broad range of potential host taxa. Here, we discuss effective techniques for analyzing blood meals.

Transposon-mediated transgenesis of mosquito vectors of disease pathogens followed the early success of transgenesis in the vinegar fly, Drosophila melanogaster. The P transposable element used in Drosophila does not function canonically in mosquitoes, and repeatable, routine transgenesis in mosquitoes was not accomplished until new transposable elements were discovered and validated. A number of distinct transposons were subsequently identified that mediate the introduction of exogenous DNA in a stable and heritable manner in mosquito species, including members of the genera Aedes, Anopheles, and Culex. The most versatile element, piggyBac, is functional in all of these mosquito genera, as well as in many other insects in diverse orders, and has been used extensively outside the class. Transposon-mediated transgenesis of recessive and dominant marker genes and reporter systems has been used to define functional fragments of gene control sequences, introduce exogenous DNA encoding products beneficial to medical interests, and act as "enhancer traps" to identify endogenous genes with specific expression characteristics.

Anautogenous female mosquitoes, which ingest a blood meal from warm-blooded vertebrates to produce eggs, have become a valuable model organism for investigating signaling pathways and physiological processes that occur during egg development. Different molecular pathways tightly regulate the initiation of egg development and are governed by a balance among different insect hormones. Gravid (mature egg-carrying) females deposit fully developed eggs at the end of each gonotrophic cycle, which is defined as the time interval between the ingestion of a blood meal to oviposition. An intact eggshell protects the oocyte and embryo inside from external factors such as desiccation, physical damage, etc., and the various eggshell proteins are spatially and temporary deposited during oogenesis. Additionally, follicle resorption (oosorption) during blood meal–induced mosquito ovarian follicle development is an adapted physiological process that optimizes reproductive fitness. Mosquito oocytes grow and mature synchronously throughout oogenesis; however, during the later stages of oogenesis, some oocytes may undergo oosorption if sufficient nutrients are unavailable. This introduction highlights how mosquito egg development can be used to investigate follicular resorption and identify proteins involved in eggshell formation in Aedes aegypti mosquitoes.

Latest SOLIDWORKS press releases, news, technical alerts and announcements. These feeds are seen on...

Latest SOLIDWORKS press releases, news, technical alerts and announcements. These feeds are seen on...

Logos II

Atlantic Crossing :: Making Logos II shipshape for a longer voyage

From an island of 1.3 million, Lisette Williams was called to go abroad on OM’s ships and share the love of Jesus with the world.

OM Ships’ Logos Hope is back in the water after 90-day dry dock marathon but more work is needed to sail again.

The Director of Public Ministries aboard Logos Hope on leading a multicultural team and the inspiration that shapes his life

After eight months of maintenance and improvements to prepare the vessel for future service, Logos Hope sets sail from Subic Bay, Philippines.

OM Ships partners with Christian ministries and celebrates four years of service for Logos Hope.

Name: Lynchee Buakham Home: Chaing Rai,Thailand Born in: April 1983 Joined OM Ships: January 2013 Previous employment: Marketing assistant Current job on board: Hotel Services team member

The story of a Dutch/Finnish family aboard Logos Hope

After a successful dry dock in Hong Kong, OM Ships’ vessel Logos Hope is en route for a two-port visit to the Philippines from the end of May.

The last crew of the Logos reunites for a never-to-be-forgotten weekend.

Madeleine Coetzer, who has served on Logos Hope for two years, tells how the Lord has changed her life.

OM Ships International celebrates five years of God’s faithfulness through the ministry of Logos Hope around the world.

Name: Caleb Epp Home: La Ronge, Canada Born in: May 1986 Joined OM Ships: February 2013 Previous employment: Carpenter ​Current job on board: Maintenance team member

Name: Sam Castro Home: Pachuca, Mexico Born in: March 1988 Joined OM Ships: September 2013 Previous employment: Veterinarian Current job on board: Shift leader in the book fair

Name: Oliviana Tugui Home: Bucharest, Romania Born in: August 1984 Joined OM Ships: February 2013 Previous employment: Teacher’s Assistant and ESL/Spanish Teacher for Primary Students Current job on board: International Café team member

OM Ships is in final preparations for the Power Up Logos Hope technical project as the four millionth visitor comes aboard in Kaohsiung, Taiwan.

From 21 July - 19 August, Logos Hope brought the hope of the Gospel to over 50,000 people who visited the ship in Incheon, South Korea.

OM Ships completes the ‘Power Up’ project and re-launches Logos Hope into active ministry.

Kuching, Malaysia :: The Logos Hope family celebrates Easter day together onboard.

Singapore :: A Frenchman makes friends with a community of foreign workers in Singapore.

Four Nigerian marine engineering students studying in Cebu, Philippines, receive practical training and spiritual encouragement through a Logos Hope engineer.

Former Logos Hope port volunteer Swens Wong discovers God’s creativity in his cake-baking business and uses his creations, and story, to bring God glory.

The world’s largest floating book fair welcomes its five millionth visitor as the tour of Asia comes to a conclusion.

Logos Hope :: A tribute to Clive Musendami

In April 2016, Logos Hope crew members travelled to over 30 different destinations around the world, involving themselves in presentations, church mobilisation, practical work and other ministry projects.

In April 2016, Logos Hope crew members travelled to over 30 different destinations around the world, involving themselves in presentations, church mobilisation, practical work and other ministry projects.

In April, Logos Hope crewmembers travelled to over 30 destinations around the world, involving themselves in presentations, church mobilisation, practical work and other projects.

In the 1980s, two babies were named after OM’s second ship. Both young men are now living out the ethos of the ministry, as servants of Christ.

The story of how OM’s Ship Ministry began

OM’s ships connect with local churches in every port of call. Existing fellowships have added new believers, and new churches have been planted in the wake of a ship visit.

Seventeen years after the Ship Ministry sailed into service, OM suffered the loss of Logos at sea. But partners around the world were adamant the work should continue, and gave generously to replace the vessel with something better.

Mosbach, Germany :: OM Ships announces the appointment of Seelan Govender as Chief Executive Officer.

In 1999, national bitterness and divisions were set aside on board Doulos, which facilitated an historic reconciliation after conflict in the Pacific islands.

Nassau, Bahamas :: The Esposito family from Argentina enjoys serving God together on board Logos Hope, bringing professional skills and supporting each other.

Six educators share tips for teaching virtually, including making time to connect personally with each student and emphasizing collaborative work.

Congress grilled the CEOs of Amazon, Apple, Facebook, and Google about "pandemic profiteering," anti-competitive practices, and the flow of misinformation about COVID-19.

In the United States, we lament the lack of diversity in STEM fields and in teacher education, but many of our actions as educators continue to "weed out" students from nondominant communities and those who are differently abled.