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1.
Adaptation to hypoxia, defined as a condition of inadequate oxygen supply, has enabled humans to successfully colonize high altitude regions. The mechanisms attempted by organisms to cope with short-term hypoxia include increased ATP production via anaerobic respiration and stabilization of Hypoxia Inducible Factor 1α (HIF-1α). However, less is known about the means through which populations adapt to chronic hypoxia during the process of development within a life time or over generations. Here we show that signaling via the highly conserved Wnt pathway impacts the ability of Drosophila melanogaster to complete its life cycle under hypoxia. We identify this pathway through analyses of genome sequencing and gene expression of a Drosophila melanogaster population adapted over >180 generations to tolerate a concentration of 3.5–4% O2 in air. We then show that genetic activation of the Wnt canonical pathway leads to increased rates of adult eclosion in low O2. Our results indicate that a previously unsuspected major developmental pathway, Wnt, plays a significant role in hypoxia tolerance. 相似文献
2.
A case of translocation heterozygosity has been discovered in gardenCanna. Morphologically the heterozygote is distinctive, being a pygmy type with small flowers which do not open. Cytologically it shows a ring or a chain of 4 plus 7 bivalents. The present observations reveal that rings disjunct usually in adjacent, and chains in an alternate manner. The subsequent course of meiosis is normal. The variety is totally sterile both after self and cross pollination. It has very likely arisen as a hybrid between two parents differing in one interchange. 相似文献
3.
Eben Goodale Hari Sridhar Kathryn E. Sieving Priti Bangal Gabriel J. Colorado Z. Damien R. Farine Eckhard W. Heymann Harrison H. Jones Indrikis Krams Ari E. Martínez Flavia Montao‐Centellas Jenny Muoz Umesh Srinivasan Anne Theo Kartik Shanker 《Biological reviews of the Cambridge Philosophical Society》2020,95(4):889-910
Mixed‐species animal groups (MSGs) are widely acknowledged to increase predator avoidance and foraging efficiency, among other benefits, and thereby increase participants' fitness. Diversity in MSG composition ranges from two to 70 species of very similar or completely different phenotypes. Yet consistency in organization is also observable in that one or a few species usually have disproportionate importance for MSG formation and/or maintenance. We propose a two‐dimensional framework for understanding this diversity and consistency, concentrating on the types of interactions possible between two individuals, usually of different species. One axis represents the similarity of benefit types traded between the individuals, while the second axis expresses asymmetry in the relative amount of benefits/costs accrued. Considering benefit types, one extreme represents the case of single‐species groups wherein all individuals obtain the same supplementary, group‐size‐related benefits, and the other extreme comprises associations of very different, but complementary species (e.g. one partner creates access to food while the other provides vigilance). The relevance of social information and the matching of activities (e.g. speed of movement) are highest for relationships on the supplementary side of this axis, but so is competition; relationships between species will occur at points along this gradient where the benefits outweigh the costs. Considering benefit amounts given or received, extreme asymmetry occurs when one species is exclusively a benefit provider and the other a benefit user. Within this parameter space, some MSG systems are constrained to one kind of interaction, such as shoals of fish of similar species or leader–follower interactions in fish and other taxa. Other MSGs, such as terrestrial bird flocks, can simultaneously include a variety of supplementary and complementary interactions. We review the benefits that species obtain across the diversity of MSG types, and argue that the degree and nature of asymmetry between benefit providers and users should be measured and not just assumed. We then discuss evolutionary shifts in MSG types, focusing on drivers towards similarity in group composition, and selection on benefit providers to enhance the benefits they can receive from other species. Finally, we conclude by considering how individual and collective behaviour in MSGs may influence both the structure and processes of communities. 相似文献
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5.
Priti Sharma Preeni Bawa Bharat Yadav Parampreet Kaur Suruchi Jindal Inderjit Yadav Satinder Kaur Kuldeep Singh Parveen Chhuneja 《Journal of plant biochemistry and biotechnology.》2020,29(1):47-55
Stripe rust (Puccinia striiformis f. sp. tritici) is one of the major devastating disease which causes large reduction in wheat yield. T. monococcum is an attractive diploid species for gene discovery in wheat with smaller genome size of 5700 Mb compared to 17,300 Mb of bread wheat. An adult plant stripe rust resistance QTL QYrtm.pau-2A was mapped on chromosome 2A flanked by two SSR markers Xwmc170 and Xwmc407. In the present study, two gene based markers Pau_Ta2AL_Gene45 and Pau_Ta2AL_Gene54 developed from 2A specific ESTs were found to map close to QYrtmpau-2A to narrow down the region for candidate gene identification. Utilizing sequence information of these two markers, four BAC clones were identified from the Minimum Tiling Path of 2AL assembly and were sequenced. SSR markers were designed from these BAC sequences and mapped to chromosome 2A. A 50 Mb region of wheat chromomse 2A was identified to harbor stripe rust resistance gene of T. monococcum. Gene based markers identified in the present investigation can be used for marker assisted introgression of QYrtm.pau-2A from T. monococcum to cultivated wheat. 相似文献
6.
The development of new starter culture of Lactococcus lactis for the manufacture of fermented dairy products with unique characteristics usually requires the isolation and identification of L. lactis up to subspecies level. Therefore, a rapid and specific PCR-RFLP assay has been developed. Forward and reverse primer sets were designed targeting the conserved house keeping gene htrA and yueF encoding a trypsin-like serine protease and a non-proteolytic protein from peptidase family M16, respectively, of L. lactis. Amplicons of 265 bp and 447 bp of htrA and yueF, respectively, were subjected to restriction fragment length polymorphism analysis. Restriction of the 265 bp amplicons with TaqI produced DNA bands of 90 bp and 175 bp with ssp. lactis, and 66 bp and 199 bp with ssp. cremoris. Similarly, restriction of PCR product of 447 bp size with AluI produced digested fragments of 125 bp and 322 bp with ssp. lactis, and 71 bp and 376 bp with ssp. cremoris. The designed primer sets were observed to be specific to L. lactis because other bacteria could not be amplified. The ssp. lactis and cremoris of L. lactis could be identified by restriction of PCR products of htrA and yueF with TaqI and AluI, respectively. 相似文献
7.
The genetic diversity of 31 identified strains of Lactococcus lactis ssp. lactis isolated from different dairy and non-dairy sources were investigated at gene level using multilocus sequence analysis (MLSA) and PCR-RFLP based on the differences in four selected partial protein coding gene sequences: araT, encoding aromatic amino acid-specific aminotransferase; dtpT, encoding di/tri peptide transporter; yueF, encoding non-proteolytic protein, peptidase, M16 family; and pdhA, encoding pyruvate dehydrogenase E1 component α-subunit. A set of seven test strains from different isolation sources and one reference strain, L. lactis ssp. lactis NCDC 094, were analyzed by MLSA. The strains showed distinct diversity among themselves and exhibited a greater percent similarity with reference strains L. lactis ssp. lactis CV56 (CP002365.1), IL1403 (AE005176.1), and KF147 (CP001834.1) in comparison with L. lactis ssp. cremoris NZ9000 (CP002094.1), MG1363 (AM406671.1), and SK11 (CP00425.1). The MLSA revealed one distinct genomic lineage within strains exclusively of L. lactis ssp. lactis. This analysis also revealed no source-wise genetic relationship in the test strains analyzed. Further, PCR-RFLP of araT, dtpT, yueF and pdhA also characterized the single genomic lineage exclusively of L. lactis ssp. lactis within a total of 24 test strains. 相似文献
8.
Eduard Kejnovsky Monika Michalovova Pavlina Steflova Iva Kejnovska Susana Manzano Roman Hobza Zdenek Kubat Jan Kovarik Manuel Jamilena Boris Vyskot 《PloS one》2013,8(1)
Sex chromosomes are an ideal system to study processes connected with suppressed recombination. We found evidence of microsatellite expansion, on the relatively young Y chromosome of the dioecious plant sorrel (Rumex acetosa, XY1Y2 system), but no such expansion on the more ancient Y chromosomes of liverwort (Marchantia polymorpha) and human. The most expanding motifs were AC and AAC, which also showed periodicity of array length, indicating the importance of beginnings and ends of arrays. Our data indicate that abundance of microsatellites in genomes depends on the inherent expansion potential of specific motifs, which could be related to their stability and ability to adopt unusual DNA conformations. We also found that the abundance of microsatellites is higher in the neighborhood of transposable elements (TEs) suggesting that microsatellites are probably targets for TE insertions. This evidence suggests that microsatellite expansion is an early event shaping the Y chromosome where this process is not opposed by recombination, while accumulation of TEs and chromosome shrinkage predominate later. 相似文献
9.
Kaur Parampreet Jindal Suruchi Yadav Bharat Yadav Inderjit Mahato Ajay Sharma Priti Kaur Satinder Gupta O. P. Vrána Jan Šimková Hana Doležel Jaroslav Gill Bikram Singh Meyer Klaus F. X. Khurana J. P. Singh N. K. Chhuneja Parveen Singh Kuldeep 《Molecular biology reports》2020,47(3):1991-2003
Molecular Biology Reports - Diploid A genome wheat species harbor immense genetic variability which has been targeted and proven useful in wheat improvement. Development and deployment of... 相似文献
10.
Marijana Popović Hadžija Marina Korolija Nikolina Jemin Iva Pavković Pajica Pavković Edita Pape Medvidović Mirko Hadžija 《Gene》2013
Genetic variants of IL-18 and IL-12B may be important in immunoregulatory abnormalities, observed in the patients with Type 1 diabetes mellitus (T1DM), that contribute to individual differences in response to a treatment. Therefore, we examined the significance of IL-18-137G/C, IL-18-607C/A, and IL-12B A/C polymorphisms in Croatians (187 patients, 236 controls), not only as factors that contribute to susceptibility to T1DM, but also as determinants of the clinical presentation of disease. 相似文献