Photosynthesis from stolen chloroplasts can support sea slug reproductive fitness

Some sea slugs are able to steal functional chloroplasts (kleptoplasts) from their algal food sources, but the role and relevance of photosynthesis to the animal host remain controversial. While some researchers claim that kleptoplasts are slowly digestible ‘snacks’, others advocate that they enhance the overall fitness of sea slugs much more profoundly. Our analysis shows light-dependent incorporation of 13 C and 15 N in the albumen gland and gonadal follicles of the sea slug Elysia timida , representing translocation of photosynthates to kleptoplast-free reproductive organs. Long-chain polyunsaturated fatty acids with reported roles in reproduction were produced in the sea slug cells using labelled precursors translocated from the kleptoplasts. Finally, we report reduced fecundity of E. timida by limiting kleptoplast photosynthesis. The present study indicates that photosynthesis enhances the reproductive fitness of kleptoplast-bearing sea slugs, confirming the biological relevance of this remarkable association between a metazoan and an algal-derived organelle.

Elucidating The Genetic Factors Contributing Towards Susceptibility And Severity Of Covid 19

: COVID-19 or SARS-CoV-2 or 2019-nCov is a pandemic disease that occurred in December 2019 from Wuhan, Hubei Province of China. It was first transmitted from the animal host to a human source, after which it followed human-human transmission and spread exponentially worldwide. Various countries have fallen prey to this virus, but there are certain countries or populations, which have been more affected by this than others. Moreover, the demographics of transmission and affected individuals are also variable from country-country. The purpose of this article is to highlight the non-modifiable risk factors for COVID-19 and their analysis in various populations affecting their susceptibility. Besides age, gender, and blood group, two major genetic factors associated with this disease are discussed here including the potential of IL-6, in causing chronic disease conditions and the rs1800795 G/C-174 IL-6 polymorphism in the IL-6 gene and with the potential role of ACE-2 receptor in viral transmission and pathogenicity with its protective and disease-causing variants.

VIRO Attack (Covid-19 Syndrome Mapping and Self-Assessment)

The new COVID-19 is caused by the virus SARS-CoV-2. The most likely ecological reservoirs for SARS-CoV-2 are bats, but it is believed that the virus jumped the species barrier to humans from another intermediate animal host. This intermediate animal host could be a domestic food animal, a wild animal, or a domesticated wild animal which has not yet been identified. WHO continues to collaborate with experts, Member States and other partners to identify gaps and research priorities for the control of COVID-19, and provide advice to countries and individuals on prevention measures. National food safety authorities have been following this event with the International Food Safety Authorities Network (INFOSAN) Secretariat to seek more information on the potential for persistence of the virus on foods traded internationally and the potential role of food in the transmission of the virus. Experiences from previous outbreaks of related coronaviruses, such as the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) show that transmission through food consumption did not occur. To date, there have not been any reports of transmission of SARS-CoV-2 virus through food. However, concerns were expressed about the potential for these viruses to persist on raw foods of animal origin.

COVID-19 Pandemic Knowledge & Perception: A Quiz Based Survey on Students in India

Emergence and spread of COVID-19 pandemic which is caused by novel coronavirus (SARS-CoV-2) is threatening the whole world. The virus originated in bats and was transmitted to humans through unknown intermediate animal host in Wuhan, Hubei province, China in December 2019. Coronavirus disease 2019 (COVID-19) outbreak needed to be put to an end and we can do this by understanding the situation better. It was of prime importance that masses particularly youngsters should have maximum knowledge of this disease in detail to check its rapid spread. Thus, this study aimed to investigate the knowledge and perceptions of students about COVID-19. With this kind of awareness, each respondent updating one’s scientific realization about this deadly virus and how to cope with this. For this purpose, an online survey was conducted using a semi-structured questionnaire using a multiple-choice questions method. A total of 1,111 responses were received. total 840 (75.60%) students from different colleges/universities and 271 (24.39%) school students have participated in this survey. The responders had a moderate level of knowledge about the COVID-19 infection and adequate knowledge about its preventive aspects. The attitude towards COVID-19 showed students' willingness to follow government guidelines on quarantine and social distancing. There is a need to intensify the awareness and address the issues of safety of students about this COVID-19 pandemic as this is still spreading at an alarming rate in India. Int. J. Appl. Sci. Biotechnol. Vol 9(2): 133-137.

Environmental Stress Selects for Innovations That Drive Vibrio Symbiont Diversity

Symbiotic bacteria in the Vibrionaceae are a dynamic group of γ-Proteobacteria that are commonly found throughout the world. Although they primarily are free-living in the environment, they can be commonly found associated with various Eukarya, either as beneficial or pathogenic symbionts. Interestingly, this dual lifestyle (free-living or in symbiosis) enables the bacteria to have enormous ecological breadth, where they can accommodate a variety of stresses in both stages. Here, we discuss some of the most common stressors that Vibrio bacteria encounter when in their free-living state or associated with an animal host, and how some of the mechanisms that are used to cope with these stressors can be used as an evolutionary advantage that increases their diversity both in the environment and within their specific hosts.

Risk-Induced Trait Responses and Non-consumptive Effects in Plants and Animals in Response to Their Invertebrate Herbivore and Parasite Natural Enemies

Predators kill and consume prey, but also scare living prey. Fitness of prey can be reduced by direct killing and consumption, but also by non-consumptive effects (NCEs) if prey show costly risk-induced trait responses (RITRs) to predators, which are meant to reduce predation risk. Recently, similarities between predators and parasites as natural enemies have been recognized, including their potential to cause victim RITRs and NCEs. However, plant-herbivore and animal host-parasite associations might be more comparable as victim-enemy systems in this context than either is to prey-predator systems. This is because plant herbivores and animal parasites are often invertebrate species that are typically smaller than their victims, generally cause lower lethality, and allow for further defensive responses by victims after consumption begins. Invertebrate herbivores can cause diverse RITRs in plants through various means, and animals also exhibit assorted RITRs to increased parasitism risk. This synthesis aims to broadly compare these two enemy-victim systems by highlighting the ways in which plants and animals perceive threat and respond with a range of induced victim trait responses that can provide pre-emptive defense against invertebrate enemies. We also review evidence that RITRs are costly in terms of reducing victim fitness or abundance, demonstrating how work with one victim-enemy system can inform the other with respect to the frequency and magnitude of RITRs and possible NCEs. We particularly highlight gaps in our knowledge about plant and animal host responses to their invertebrate enemies that may guide directions for future research. Comparing how potential plant and animal victims respond pre-emptively to the threat of consumption via RITRs will help to advance our understanding of natural enemy ecology and may have utility for pest and disease control.

Photosynthesis from stolen chloroplasts increases sea slug reproductive fitness

Some sea slugs are able to steal functional chloroplasts (kleptoplasts) from their algal food sources, but the role and relevance of photosynthesis to the animal host remain controversial. While some researchers claim that kleptoplasts are slowly digestible snacks, others advocate that they enhance the overall fitness of sea slugs much more profoundly. Our analysis show light-dependent incorporation of 13C and 15N in the albumen gland and gonadal follicles of the sea slug Elysia timida, representing translocation of photosynthates to kleptoplast-free reproductive organs. Long-chain polyunsaturated fatty acids with reported roles in reproduction were produced in the sea slug cells using labelled precursors translocated from the kleptoplasts. Finally, we report reduced fecundity of E. timida by suppressing kleptoplast photosynthesis. The present study provides the first thorough experimental evidence that photosynthesis enhances the reproductive fitness of kleptoplast-bearing sea slugs, confirming the biological relevance of this remarkable association between a metazoan and an algal-derived organelle.

Disruption of the odorant coreceptor Orco impairs foraging and host finding behaviors in the New World screwworm fly

The evolution of obligate ectoparasitism in blowflies (Diptera: Calliphoridae) has intrigued scientists for over a century, and surprisingly, the genetics underlying this lifestyle remain largely unknown. Blowflies use odors to locate food and oviposition sites; therefore, olfaction might have played a central role in niche specialization within the group. In insects, the coreceptor Orco is a required partner for all odorant receptors (ORs), a major gene family involved in olfactory-evoked behaviors. Hence, we characterized the Orco gene in the New World screwworm, Cochliomyia hominivorax, a blowfly that is an obligate ectoparasite of warm-blooded animals. In contrast, most of the closely related blowflies are scavengers that lay their eggs on dead animals. We show that the screwworm Orco orthologue (ChomOrco) is highly conserved within Diptera, showing signals of strong purifying selection. Expression of ChomOrco is broadly detectable in chemosensory appendages, and is related to morphological, developmental, and behavioral aspects of the screwworm biology. We used CRISPR/Cas9 to disrupt ChomOrco and evaluate the consequences of losing the OR function on screwworm behavior. In two-choice assays, Orco mutants displayed an impaired response to floral-like and animal host-associated odors, suggesting that OR-mediated olfaction is involved in foraging and host-seeking behaviors in C. hominivorax. These results broaden our understanding of the chemoreception basis of niche occupancy by blowflies.

The oviposition cue indole inhibits animal-host attraction in Aedes aegypti mosquitoes

Mosquitoes represent a major source of disease transmission and possess the uncanny ability to locate suitable animal-hosts, a feature mediated by their exquisite olfactory system. Insect repellents such as N,N-Diethyl-meta-toluamide, also called DEET, have been shown to activate and inhibit mosquito odorant receptors resulting in behavioral modulation. This and other repellents available for personal protection against mosquitoes are topically applied on the skin and operate at short range. In our search for potential long-range odorant repellents, we have hypothesized that the shared chemical similarities between indole and DEET, may confer the former the ability to block odorant receptor function and inhibit human-host attraction. Using the two-electrode voltage clamp of Xenopus laevis oocytes as a pharmacological platform, we provide evidence that indole inhibits the Aedes aegypti (R)-1-octen-3-ol receptor OR8, a receptor involved in the decision of female mosquitoes to identify human hosts. Coincidentally, we also show that indole inhibits the animal-host seeking behavior of female Aedes aegypti. Together, our findings suggests that indole may be a candidate spatial repellent for the long-range protection of humans against mosquito bites.