Month: September 2022

SYMBIONTS DEFINE MATE SELECTION. "In sexual reproduction different types of symbiotic relationships between insects and microbes have become established. For example, some bacteria have evolved almost exclusive vertical transmission and even define the compatibility of insect mating partners. Many strictly sexually transmitted diseases have also been described in insects." https://lnkd.in/dChz5SR View in LinkedIn

ONGOING ENDOSYMBIOTIC EVENTS. "In insects mutualistic symbionts are often associated with nutritional aspects where hosts build obligate relationships with endosymbionts. Most mutualists are in an evolutionary long-lasting host–symbiont relationship and have evolved complete vertical transmission. Among those the most specific relationships have evolved as intracellular vertical transmission, very similar to mitochondria or chloroplasts." https://lnkd.in/dChz5SR View in LinkedIn

SYMBIONT FERTILIZATION CONTROL. "Many other heritable endosymbionts are facultative and not absolutely required by their host for survival and reproduction. Although endosymbionts are not directly associated with genitalia, they still form an important part of insect reproduction as manipulators of fertilization." https://lnkd.in/dChz5SR View in LinkedIn

PURGING COMPETITORS. "Due to imperfect vertical transmission and potential physiological costs imposed on hosts, facultative endosymbionts are relying on various manipulative strategies to persist in a host population. For example, some are male-killers or exert cytoplasmatic incompatibility (CI) when their host engages in reproduction with a partner that harbors an unrelated endosymbiont." https://lnkd.in/dChz5SR View in LinkedIn

SO ENDS this contemplation of hereditable endosymbionts, a half-way stop in the spectrum to engulfment of algae to make a permanent organelle such as a chloroplast and mitochondrion. Clearly, there are many examples in nature where critically important symbiotic organisms are inherited, mostly maternally, by a variety of mechanisms, ensuring that the offspring have immediate inoculations of these outsourced metabolic factories. View in LinkedIn

VIRAL ECOSYSTEM. "Similar to gut bacteria, interpersonal variation in the virome is high. Changing the focus from individual agents that are implicated in disease toward a community view has already precipitated paradigm shifts in the view of the virome and disease, and the same will likely be true for eukaryotic microbes." https://lnkd.in/dRUEtkS View in LinkedIn

EVERYWHERE. "Viruses are ubiquitous companions of cellular life forms: it appears that every cellular organism studied has its own viruses or, at least, virus-like selfish genetic elements. Recent environmental studies have shown that viruses, primarily, bacteriophages, are "most abundant biological entities on the planet", with the total number of virus particles exceeding the number of cells by at least an order of magnitude." https://lnkd.in/dHhQ6QH View in LinkedIn

DOMINANT LIFESTYLE. "We have heard much about non-coding RNAs, mobile genetic elements, repeat sequences, and introns— all of them formerly being termed ‘‘junk,’’ but now we can imagine these as remnants of persistent viral infection events. Thus, the persistent viral lifestyle is the most dominant biological lifestyle on this planet." https://lnkd.in/eWydwab View in LinkedIn

VIRAL DIVERSITY. "A remarkable feature of viruses is the diversity of their genetic cycles, in a sharp contrast to the uniformity of the cellular genetic cycle. Viruses with different genome strategies span a vast range of genome sizes (the genomes of the largest known virus, the mimivirus, and the smallest viruses, e.g., circoviruses, differ by three orders of magnitude) and show a non-uniform and non-trivial distribution among the host taxa." https://lnkd.in/dHhQ6QH View in LinkedIn

VIRAL NICHES. "The extraordinary diversity of double-stranded (ds) DNA bacteriophages is in a stark contrast to the absence of bona fide dsDNA viruses in plants. Conversely, RNA viruses are extremely abundant and diverse in plants and animals but are currently represented by only two compact families in bacteria, and so far have not been detected in archaea." https://lnkd.in/dHhQ6QH View in LinkedIn