Fungiculture in termites is associated with a mycolytic gut bacterial community

ABSTRACT Termites forage on a range of substrates, and it has been suggested that diet shapes the composition and function of termite gut bacterial communities. Through comparative analyses of gut metagenomes in nine termite species with distinct diets, we characterize bacterial community compositions and use peptide-based functional annotation method to determine biomass-degrading enzymes and the bacterial taxa that encode them. We find that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, while wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Interestingly, wood-feeding termite gut bacterial genes code for abundant chitinolytic enzymes, suggesting that fungal biomass within the decaying wood likely contributes to gut bacterial or termite host nutrition. Across diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community composition, with the most marked difference being the communities coding for the mycolytic capacity of the fungus-growing termite gut. IMPORTANCE Understanding functional capacities of gut microbiomes is important to improve our understanding of symbiotic associations. Here, we use peptide-based functional annotation to show that the gut microbiomes of fungus-farming termites code for a wealth of enzymes that likely target the fungal diet the termites eat. Comparisons to other termites showed that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, whereas wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Across termites with different diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community compositions

The functional implications of Termitomyces domestication on fungus-growing termite gut microbiomes

Patients with chronic or recurrent otitis media with effusion who do not respond to treatment with conventional ventilation tubes are often treated with long-term ventilation tubes. The aim of this retrospective study was to determine the extrusion and complication rates of long-term ventilation tubes. The median ventilation time of the tubes was 31.5 months. The most common complication was otorrhoea. One episode of otorrhoea occurred after 24% of all tube insertions, and recurrent otorrhoea occurred in 29%. A persisting perforation developed in 19% after extrusion or removal of the tube. Other, mostly minor, complications occurred in 36% with the tube in situ and in 3% after extrusion or removal of the tube. Long-term ventilation tubes provided prolonged ventilation of the middle ear, but also resulted in a considerable number of complications. For each individual case, one should therefore determine whether the advantages of long-term ventilation tubes outweigh the possible complications in view of the available alternatives for middle ear ventilation

Reciprocal genomic evolution in the ant-fungus agricultural symbiosis

The attine ant–fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. Here we document reciprocal shifts in the genomes and transcriptomes of seven fungus-farming ant species and their fungal cultivars. We show that ant subsistence farming probably originated in the early Tertiary (55–60 MYA), followed by further transitions to the farming of fully domesticated cultivars and leaf-cutting, both arising earlier than previously estimated. Evolutionary modifications in the ants include unprecedented rates of genome-wide structural rearrangement, early loss of arginine biosynthesis and positive selection on chitinase pathways. Modifications of fungal cultivars include loss of a key ligninase domain, changes in chitin synthesis and a reduction in carbohydrate-degrading enzymes as the ants gradually transitioned to functional herbivory. In contrast to human farming, increasing dependence on a single cultivar lineage appears to have been essential to the origin of industrial-scale ant agriculture

Dwelling as the life basis of Ukrainians

На прикладі містечок Батурина, Глухова, Борзни та Кролевця у статті розглядається інтер’єр жител населення Чернігово-Сіверщини (друга половина ХVІІІ – середина ХІХ ст.). На основі значного описового матеріалу, стосовно звичаїв і побуту українців, який накопичився в середині і особливо в другій половині ХІХ ст. можна зробити науково-вивірені узагальнення з приводу порівняльної характеристики українців і росіян. Дослідженням цієї теми займалися М. Маркевич, І. Срезнєвський, П. Куліш та ін. Значний внесок до вивчення даної проблематики належить історику М. Костомарову, який виокремив український культурний і традиційно-буттєвий комплекс із загальноросійського, що утрадиційнилось як спільне за понад сторіччя співжиття в рамках однієї імперії. Також у даній статті характеризується поділ оселі на умовні частини та визначаються основні сакральні центри хати. Автор наголошує на глибокому символічному обрядово-ритуальному значенні, яке українці надавали всім предметам хатнього інтер’єру та наголошує на ліричній прив’язаності їх до місця свого проживання.На примере городков Батурина, Глухова, Борзны и Кролевца в статье рассматривается интерьер жилищ населения Чернигово-Северщины во второй половине XVIII – середине XIX вв. На основе материалов, описывающих украинские обычаи и быт, накопившихся в средине, а особенно во второй половине XIX в., можно сделать обобщения по поводу сравнительной характеристики украинцев и русских. Исследованием этой темы занимались Н. Маркевич, И. Срезневский, П. Кулиш и другие ученые. Значительный вклад в изучение данной проблематики принадлежит историку Н. Костомарову, который выделил украинский культурный и традиционно- бытейный комплекс из общероссийского, которые сосуществовали более столетия в границах одной империи. Также в данной статье характеризируется разделение жилища на условные части и определяются основные сакральные центры дома (хаты). Автор отмечает глубокое символическое ритуально-обрядовое значение, которое украинцы придавали всем предметам домашнего интерьера, а также подчеркивает лирическую привязанность населения к месту его проживания.Article deals with the interior of dwellings in Chernihiv-Siverskyi region (in the 2nd half of the ХVІІІ – 1st half of the ХІХ cent.). On the example of towns Baturyn, Glukhiv, Borzna and Krolevets the article deals with the house interiors of the population of Chernihovo-Sivershchyna (the second half of the XVIII – mid. XIX cent.). The analysis is based on considerable descriptive material concerning Ukrainian customs and way of life that has accumulated in the middle and especially in the second half of the XIX cent. and led to scientific adjusted conclusion about the comparative characteristics of Ukrainians and Russians. This topic was researched by M. Markevych, I. Sreznevskyi, P. Kulish and others. A significant contribution to the study of this subject belongs to historian M. Kostomarov, who singled Ukrainian cultural and traditional existential complex out of all-Russian complex, that was considered unified for more than three centuries of coexistence within a single empire. Also, this article characterizes the division of the house on special parts and identifies the main sacred centres of the house. The attention is given to the fact that the Ukrainian housing is associated with many beliefs and rituals. It indicates that the dwelling-house reflects not only people’s ideological and artistic heritage, but also a pragmatic idea. After all, the house seemed a model of nature and the universe, which protected both physically and spiritually. We know that house was not only a place where the family spent most of its life, but it was the family hearth around which ancient and beautiful traditions were preserved. The author emphasizes the deep symbolic ritual value that Ukrainians gave to all subjects of domestic interior and the lyrical attachment to their place of residence. After all, the house had a kind of sacred meaning for its tenants, that is why, to the house and all domestic things people gave some philosophical content. Complexity of representations of the world for humans began from the dwelling and was a dominant through all life. It is revealed that a Ukrainian house with its aesthetic appearance and its interior in particular, is an important factor in the understanding of the Ukrainian people and makes the character unique, and one that is very different from the characteristics of other nations. The author concluded that this topic needs a further study

Hemimetabolous genomes reveal molecular basis of termite eusociality

Around 150 million years ago, eusocial termites evolved from within the cockroaches, 50 million years before eusocial Hymenoptera, such as bees and ants, appeared. Here, we report the 2-Gb genome of the German cockroach, Blattella germanica, and the 1.3-Gb genome of the drywood termite Cryptotermes secundus. We show evolutionary signatures of termite eusociality by comparing the genomes and transcriptomes of three termites and the cockroach against the background of 16 other eusocial and non-eusocial insects. Dramatic adaptive changes in genes underlying the production and perception of pheromones confirm the importance of chemical communication in the termites. These are accompanied by major changes in gene regulation and the molecular evolution of caste determination. Many of these results parallel molecular mechanisms of eusocial evolution in Hymenoptera. However, the specific solutions are remarkably different, thus revealing a striking case of convergence in one of the major evolutionary transitions in biological complexity

Molecular traces of alternative social organization in a termite genome

Although eusociality evolved independently within several orders of insects, research into the molecular underpinnings of the transition towards social complexity has been confined primarily to Hymenoptera (for example, ants and bees). Here we sequence the genome and stage-specific transcriptomes of the dampwood termite Zootermopsis nevadensis (Blattodea) and compare them with similar data for eusocial Hymenoptera, to better identify commonalities and differences in achieving this significant transition. We show an expansion of genes related to male fertility, with upregulated gene expression in male reproductive individuals reflecting the profound differences in mating biology relative to the Hymenoptera. For several chemoreceptor families, we show divergent numbers of genes, which may correspond to the more claustral lifestyle of these termites. We also show similarities in the number and expression of genes related to caste determination mechanisms. Finally, patterns of DNAmethylation and alternative splicing support

Comparative genomics reveals insights into avian genome evolution and adaptation

Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits