Ammonia transport in the excretory system of mosquito larvae (Aedes aegypti): Rh protein expression and the transcriptome of the rectum.

The role of the mosquito excretory organs (Malpighian tubules, MT and hindgut, HG) in ammonia transport as well as expression and function of the Rhesus (Rh protein) ammonia transporters within these organs was examined in Aedes aegypti larvae and adult females. Immunohistological examination revealed that the Rh proteins are co-localized with V-type H-ATPase (VA) to the apical membranes of MT and HG epithelia of both larvae and adult females. Of the two Rh transporter genes present in A.

Osmoregulatory Challenges Faced by Mosquitoes and Techniques for Studying the Transporters Involved in Their Adaptations.

Mosquitoes are the most important disease vector in the world, and gaining knowledge of their physiology to develop novel population control strategies has been a focus of research for some time. Both aquatic larvae and terrestrial adults face harsh environmental factors that severely challenge their salt and water balance, which are regulated by the function of epithelia of various organs. The regulated passage of water and solutes across epithelia occurs, in part, through transporters expressed in epithelial cell membranes.

Localizing Protein Expression of Transporters in Epithelial Cell Membranes of Mosquitoes.

Identifying and localizing ion transport proteins in epithelia is important for understanding how these tissues can regulate salt and water balance in animals. Mosquitoes face distinct challenges regarding salt and water balance as larvae live in water of varying ionic composition while adult female mosquitoes must deal with periodic large blood meals. This protocol will explain how to localize ion transporters in epithelia of mosquitoes.

Ocean acidification alters foraging behaviour in Dungeness crab through impairment of the olfactory pathway.

Crustacean olfaction is fundamental to most aspects of living and communicating in aquatic environments and more broadly, for individual- and population-level success. Accelerated ocean acidification from elevated CO threatens the ability of crabs to detect and respond to important olfactory-related cues. Here, we demonstrate that the ecologically and economically important Dungeness crab (Metacarcinus magister) exhibits reduced olfactory-related antennular flicking responses to a food cue when exposed to near-future CO levels, adding to the growing body of evidence of impaired crab behaviour.

Hiat1 as a new transporter involved in ammonia regulation.

The orphan transporter hippocampus-abundant transcript 1 (Hiat1) was first identified in the mammalian brain. Its specific substrate specificity, however, has not been investigated to date. Here, we identified and analyzed Hiat1 in a crustacean, the green crab Carcinus maenas.

The transcriptome of anal papillae of Aedes aegypti reveals their importance in xenobiotic detoxification and adds significant knowledge on ion, water and ammonia transport mechanisms.

The anal papillae of mosquito larvae are osmoregulatory organs in direct contact with the external aquatic environment that actively sequester ions and take up water in dilute freshwater. In the disease vector Aedes aegypti mechanisms of ion, water and ammonia transport have only been partially resolved. Furthermore, A.

Ammonium transporter expression in sperm of the disease vector mosquito influences male fertility.

The ammonium transporter (AMT)/methylammonium permease (MEP)/Rhesus glycoprotein (Rh) family of ammonia (NH/NH) transporters has been identified in organisms from all domains of life. In animals, fundamental roles for AMT and Rh proteins in the specific transport of ammonia across biological membranes to mitigate ammonia toxicity and aid in osmoregulation, acid-base balance, and excretion have been well documented. Here, we observed enriched () mRNA levels within reproductive organs of the arboviral vector mosquito, , prompting us to explore the role of AMTs in reproduction.

A comparison of aquaporin expression in mosquito larvae (Aedes aegypti) that develop in hypo-osmotic freshwater and iso-osmotic brackish water.

The mosquito Aedes aegypti vectors the arboviral diseases yellow fever, dengue, Zika and chikungunya. Larvae are usually found developing in freshwater; however, more recently they have been increasingly found in brackish water, potential habitats which are traditionally ignored by mosquito control programs. Aedes aegypti larvae are osmo-regulators maintaining their hemolymph osmolarity in a range of ~ 250 to 300 mOsmol l-1.

Development of Aedes aegypti (Diptera: Culicidae) mosquito larvae in high ammonia sewage in septic tanks causes alterations in ammonia excretion, ammonia transporter expression, and osmoregulation.

Larvae of the disease vector mosquito, Aedes aegypti (L.) readily develop in ammonia rich sewage in the British Virgin Islands. To understand how the larvae survive in ammonia levels that are lethal to most animals, an examination of ammonia excretory physiology in larvae collected from septic-water and freshwater was carried out.

Evidence that Rh proteins in the anal papillae of the freshwater mosquito are involved in the regulation of acid-base balance in elevated salt and ammonia environments.

commonly inhabit ammonia-rich sewage effluents in tropical regions of the world where the adults are responsible for the spread of disease. Studies have shown the importance of the anal papillae of in ion uptake and ammonia excretion. The anal papillae express ammonia transporters and Rhesus (Rh) proteins which are involved in ammonia excretion and studies have primarily focused on understanding these mechanisms in freshwater.

Ammonia Excretion in an Osmoregulatory Syncytium Is Facilitated by AeAmt2, a Novel Ammonia Transporter in Larvae.

The larvae of the mosquito inhabit ammonia rich septic tanks in tropical regions of the world that make extensive use of these systems, explaining the prevalence of disease during dry seasons. Since ammonia (NH/[Formula: see text]) is toxic to animals, an understanding of the physiological mechanisms of ammonia excretion permitting the survival of larvae in high ammonia environments is important. We have characterized a novel ammonia transporter, , belonging to the Amt/MEP/Rh family of ammonia transporters.

Ca levels in Daphnia hemolymph may explain occurrences of daphniid species along recent Ca gradients in Canadian soft-water lakes.

Calcium levels are declining in eastern North American and western European lakes. This widespread issue is affecting the composition of crustacean zooplankton communities, as the presence and abundance of several calcium-rich daphniid species are declining, while two other daphniids, D. catawba and D.

Rhesus glycoproteins contribute to ammonia excretion by larval anal papillae.

In larval , transcripts of the Rhesus-like glycoproteins and have been detected in the anal papillae, sites of ammonia (NH/NH) excretion; however, these putative ammonia transporters have not been previously localized or functionally characterized. In this study, we show that the AeRh50s co-immunolocalize with apical V-type H-ATPase as well as with basal Na/K-ATPase in the epithelium of anal papillae. The double-stranded RNA-mediated knockdown of and resulted in a significant reduction in AeRh50 protein abundance in the anal papillae, and this was coupled to decreased ammonia excretion.

Ultrasound detection of lung hepatization.

Bedside ultrasound interrogation of the thorax can aide the clinician in determining the cause of the respiratory dysfunction. Often plain radiographs are not sufficient to differentiate pathology. We present a case in which bedside ultrasound defined the pathology without the need for further imaging.