All songbirds studied so far have a germline-restricted chromosome (GRC), which is present in the germ cells and absent in the somatic cells. It shows a wide variation in size, morphology, and genetic content between the songbird species. In this paper, we analyzed GRC behavior in female and male meiosis of the great tit, using immunolocalization of meiotic proteins and FISH with GRC-derived DNA probes. We found that, despite dozens of million years of independent evolution, the great tit GRC displays a striking similarity with the GRCs of two species of martins and two species of estrildid finches examined earlier. It was usually present in two copies in females forming recombining bivalent and in one copy in males forming a condensed heterochromatic body with dotted-like axial elements of the synaptonemal complex. We observed mosaicism for the GRC copy number in the female and male great tit. This indicates that one of the GRC copies might be passively lost during premeiotic germ cell divisions. After the meiotic prophase, the GRC was ejected from most male germ cells. The reverse and interspecies FISH with GRC-specific microdissected DNA probes indicates that GRCs of the great tit, pale martin, and zebra finch differ substantially in their genetic content despite similarities in the meiotic behavior.

We analyzed the synapsis and recombination between Z and W chromosomes in the oocytes of nine neognath species: domestic chicken Gallus gallus domesticus, grey goose Anser anser, black tern Chlidonias niger, common tern Sterna hirundo, pale martin Riparia diluta, barn swallow Hirundo rustica, European pied flycatcher Ficedula hypoleuca, great tit Parus major and white wagtail Motacilla alba using immunolocalization of SYCP3, the main protein of the lateral elements of the synaptonemal complex, and MLH1, the mismatch repair protein marking mature recombination nodules. In all species examined, homologous synapsis occurs in a short region of variable size at the ends of Z and W chromosomes, where a single recombination nodule is located. The remaining parts of the sex chromosomes undergo synaptic adjustment and synapse non-homologously. In 25% of ZW bivalents of white wagtail, synapsis and recombination also occur at the secondary pairing region, which probably resulted from autosome−sex chromosome translocation. Using FISH with a paint probe specific to the germline-restricted chromosome (GRC) of the pale martin on the oocytes of the pale martin, barn swallow and great tit, we showed that both maternally inherited songbird chromosomes (GRC and W) share common sequences.

All songbirds studied to date have an additional Germline Restricted Chromosome (GRC), which is not present in somatic cells. GRCs show a wide variation in genetic content and little homology between species. To check how this divergence affected the meiotic behavior of the GRC, we examined synapsis, recombination and copy number variation for GRCs in the closely related sand and pale martins ( Riparia riparia and R. diluta ) in comparison with distantly related estrildid finches. Using immunolocalization of meiotic proteins and FISH with GRC-specific DNA probes, we found a striking similarity in the meiotic behavior of GRCs between martins and estrildid finches despite the millions of years of independent evolution. GRCs are usually present in two copies in female and in one copy in male pachytene cells. However, we detected polymorphism in female and mosaicism in male martins for the number of GRCs. In martin and zebra finch females, two GRCs synapse along their whole length, but recombine predominately at their ends. We suggest that the shared features of the meiotic behavior of GRCs have been supported by natural selection in favor of a preferential segregation of GRCs to the eggs.

Heterochiasmy, a sex-based difference in recombination rate, has been detected in many species of animals and plants. Several hypotheses about evolutionary causes of heterochiasmy were proposed. However, there is a shortage of empirical data. In this paper, we compared recombination related traits in females and males of the barn swallow Hirundo rustica (Linnaeus, 1758), the species under strong sexual selection, with those in the pale martin Riparia diluta (Sharpe and Wyatt, 1893), a related and ecologically similar species with the same karyotype (2N = 78), but without obvious sexual dimorphism. Recombination traits were examined in pachytene chromosome spreads prepared from spermatocytes and oocytes. Synaptonemal complexes and mature recombination nodules were visualized with antibodies to SYCP3 and MLH1 proteins, correspondingly. Recombination rate was significantly higher (p = 0.0001) in barn swallow females (55.6 ± 6.3 recombination nodules per autosomal genome), caused by the higher number of nodules at the macrochromosomes, than in males (49.0 ± 4.5). They also showed more even distribution of recombination nodules along the macrochromosomes. At the same time, in the pale martin, sexual differences in recombination rate and distributions were rather small. We speculate that an elevated recombination rate in the female barn swallows might have evolved as a compensatory reaction to runaway sexual selection in males.

An unusual supernumerary chromosome has been reported for two related avian species, the zebra and Bengalese finches. This large, germline-restricted chromosome (GRC) is eliminated from somatic cells and spermatids and transmitted via oocytes only. Its origin, distribution among avian lineages, and function were mostly unknown so far. Using immunolocalization of key meiotic proteins, we found that GRCs of varying size and genetic content are present in all 16 songbird species investigated and absent from germline genomes of all eight examined bird species from other avian orders. Results of fluorescent in situ hybridization of microdissected GRC probes and their sequencing indicate that GRCs show little homology between songbird species and contain a variety of repetitive elements and unique sequences with paralogs in the somatic genome. Our data suggest that the GRC evolved in the common ancestor of all songbirds and underwent significant changes in the extant descendant lineages.

Background: Meiotic recombination is an important source of genetic variability.Studies on mammals demonstrate a substantial interspecies variation in overall recombination rate, which is dependent mainly on chromosome（2 n） and chromosome arm number（FN）.Bird karyotypes are very conservative with 2 n being about 78–82 and FN being 80–90 in most species.However, some families such as Apodidae（swifts） and Falconidae（falcons） show a substantial karyotypic variation.In this study, we describe the somatic and pachytene karyotypes of the male Common Swift（Apus apus） and the pachytene karyotype of the male Eurasian Hobby（Falco subbuteo） and estimate the overall number and distribution of recombination events along the chromosomes of these species.Methods: The somatic karyotype was examined in bone marrow cells.Pachytene chromosome spreads were prepared from spermatocytes of adult males.Synaptonemal complexes and mature recombination nodules were visualized with antibodies to SYCP3 and MLH1 proteins correspondingly.Results: The karyotype of the Common Swift consists of three metacentric, three submetacentric and two telocentric macrochromosomes and 31 telocentric microchromosomes（2 n = 78; FN = 90）.It differs from the karyotypes of related Apodidae species described previously.The karyotype of the Eurasian Hobby contains one metacentric and 13 telocentric macrochromosomes and one metacentric and ten telocentric microchromosomes（2 n = 50; FN = 54） and is similar to that described previously in 2 n, but differs for macrochromosome morphology.Despite an about 40% difference in 2 n and FN, these species have almost the same number of recombination nodules per genome: 51.4 ± 4.3 in the swift and 51.1 ± 6.7 in the hobby.The distribution of the recombination nodules along the macrochromosomes was extremely polarized in the Common Swift and was rather even in the Eurasian Hobby.Conclusions: This study adds two more species to the short list of birds in which the number and distribution of recombination nodules have been examined.Our data confirm that recombination rate in birds is substantially higher than that in mammals, but shows rather a low interspecies variability.Even a substantial reduction in chromosome number does not lead to any substantial decrease in recombination rate.More data from different taxa are required to draw statistically supported conclusions about the evolution of recombination in birds.

По данным автоматического трассирования движения клещей в чашке Петри проанализирована мотивационная изменчивость спонтанной активности и поведенческого ответа таежного клеща на запаховые стимулы. В исследованной выборке выделено две группы клещей, отличающихся по траектории передвижения в отсутствие стимула: клещи, которые перемещались преимущественно по краю чашки на максимально доступной высоте (группа 1), клещи, которые перемещались в основном по дну и стенке чашки (группа 2). Отмечено, что клещи группы 1 в отличие от клещей группы 2 демонстрировали выраженный поведенческий ответ на запаховые стимулы (синтетические феромоны человека и аммиак) и отрицательный геотаксис. Установлено, что принадлежность к этим группам зависела от времени суток, в которое проводили тестирование, и не зависела от физиологического возраста и инфекционного статуса.

According to -the automatic tracing of the movement of ticks in a Petri dish, motivational variability of the spontaneous activity and behavioral response of the taiga tick to olfactory stimuli was analyzed. In the studied sample, two groups of ticks that differ in the movement trajectory in the absence of stimulus were isolated, including ticks that mainly moved on the edge of the dish at maximum accessible height (group 1) and ticks that mainly moved at the bottom and wall of the dish (group 2). It was registered that ticks of group 1 (as opposed to ticks of group 2) demonstrated a pronounced behavioral response to olfactory stimuli (human synthetic pheromones and ammonia) and negative geotaxis. It was established that belonging to these groups depended On the time of day when the testing was performed and did not depend on the physiological age and infectious status.

The effect of metabolic syndrome risk factors on the content of light hydrocarbons (C2-C3) in exhaled air has been studied with the participation of students of Novosibirsk State Medical University. Gas chromatography was performed in an EKHO-EW-FID chromatograph with a short multichannel column. The study revealed sex-related differences between the concentrations of light hydrocarbons in exhaled air. In addition, some factors, such as smoking and type 2 diabetes mellitus in relatives, affect the content of C2-C3 compounds in exhaled air of women only. However, overweight is correlated with the content of acetone (C3) in exhaled air only in men. Thus, the metabolic changes caused by the presence of age-specific metabolic syndrome risk factors lead to the changes in the gas composition of exhaled air and can be detected and used for early diagnosis.

The article gives the researches of correlation between metabolic disturbances for two-type diabetes with the acetone concentration in exhaled breath. The regulatory contours reflecting the varieties of pathogenesis metabolic disturbances were revealed, that is purposely for early diagnostic criteria and differentiated preventive methods of this disease's treating and correction.

Институт цитологии и генетики СО РН (г. Новосибирск) Исследованы корреляции общепринятых факторов риска метаболических нарушений, типичных для сахарного диабета, с содержанием легких углеводородов (C2–C3) в выдыхаемом воздухе, для определения которых использовали портативный поликапиллярный хроматограф ЭХО-В-ФИД. На основании оценки выдыхаемого воздуха у практически здоровых студентов показана прогностическая и диагностическая значимости регистрации легких углеводородов как ранних маркеров развития сахарного диабета. Ключевые слова: газовая хроматография, сахарный диабет, ацетон, факторы риска Куликов Вячеслав Юрьевич – доктор медицинских наук, профессор, заслуженный деятель науки РФ, заведующий кафедрой нормальной физиологии ГОУ ВПО «Новосибирский государственный медицинский университет Росздрава», рабочий телефон: (383) 225-07-37 Руяткина Людмила Александровна – доктор медицинских наук, профессор, заведующая курсом клинической и неотложной эндокринологии ФПК и ППВ ГОУ ВПО «Новосибирский государственный медицинский университет Росздрава», рабочий телефон : (383) 226-39-01 Сорокин Олег Викторович – кандидат медицинских наук, доцент кафедры нормальной физиологии ГОУ ВПО «Новосибирский государственный медицинский университет Росздрава», рабочий телефон: (383) 225-07-37 Шабанова Елена Сергеевна – аспирант кафедры клинической и неотложной эндокринологии ФПК и ППВ ГОУ ВПО «Новосибирский государственный медицинский университет Росздрава», рабочий телефон : (383) 226-39-01