Project description:We have conducted a season and subspecies comparasion on the two Willow Warbler subspecies Phylloscopus trochilus trochilus and Phylloscopus trochilus acredula. The analysis were performed by hybridizing cDNA from the Willow Warbler (Phylloscopus trochilus) on a Affymetrix costum array designed for the zebra finch (Taeniopygia guttata), the Lund-zf array.
Project description:Interactions between avian hosts and brood parasites can provide a model for how animals adapt to a changing world. Reed warbler (Acrocephalus scirpaceus) hosts employ costly defenses to combat parasitism by common cuckoos (Cuculus canorus). During the past three decades cuckoos have declined markedly across England, reducing parasitism at our study site (Wicken Fen) from 24% of reed warbler nests in 1985 to 1% in 2012. Here we show with experiments that host mobbing and egg rejection defenses have tracked this decline in local parasitism risk: the proportion of reed warbler pairs mobbing adult cuckoos (assessed by responses to cuckoo mounts and models) has declined from 90% to 38%, and the proportion rejecting nonmimetic cuckoo eggs (assessed by responses to model eggs) has declined from 61% to 11%. This is despite no change in response to other nest enemies or mimetic model eggs. Individual variation in both defenses is predicted by parasitism risk during the host's egg-laying period. Furthermore, the response of our study population to temporal variation in parasitism risk can also explain spatial variation in egg rejection behavior in other populations across Europe. We suggest that spatial and temporal variation in parasitism risk has led to the evolution of plasticity in reed warbler defenses.
Project description:Macaque species share over 93% genome homology with humans and develop many disease phenotypes similar to those of humans, making them valuable animal models for the study of human diseases (e.g.,HIV and neurodegenerative diseases). However, the quality of genome assembly and annotation for several macaque species lags behind the human genome effort. To close this gap and enhance functional genomics approaches, we employed a combination of de novo linked-read assembly and scaffolding using proximity ligation assay (HiC) to assemble the pig-tailed macaque (Macaca nemestrina) genome. This combinatorial method yielded large scaffolds at chromosome-level with a scaffold N50 of 127.5 Mb; the 23 largest scaffolds covered 90% of the entire genome. This assembly revealed large-scale rearrangements between pig-tailed macaque chromosomes 7, 12, and 13 and human chromosomes 2, 14, and 15. We subsequently annotated the genome using transcriptome and proteomics data from personalized induced pluripotent stem cells (iPSCs) derived from the same animal. Reconstruction of the evolutionary tree using whole genome annotation and orthologous comparisons among three macaque species, human and mouse genomes revealed extensive homology between human and pig-tailed macaques with regards to both pluripotent stem cell genes and innate immune gene pathways. Our results confirm that rhesus and cynomolgus macaques exhibit a closer evolutionary distance to each other than either species exhibits to humans or pig-tailed macaques. These findings demonstrate that pig-tailed macaques can serve as an excellent animal model for the study of many human diseases particularly with regards to pluripotency and innate immune pathways.
Project description:Real-time quantitative PCR (RT–qPCR) is the favoured method for gene expression analysis in molecular biology due to its sensitivity, specificity, cost-effectiveness, and reproducibility. To obtain the accuracy and reliability of RT-qPCR, the use of reliable reference genes is inevitable. There were many reports about the physiological response of giant reed (Arundo donax L.) to abiotic stresses. However, there is little use in the validation of reference genes under different treatments. It still belongs to the blank that the research about selecting reference genes under salt and alkali. In this study, the expression stability of twenty-three candidate reference genes in leaves and roots were assessed under salt, drought, and alkali stresses using geNorm, NormFinder, BestKeeper, and Delta Ct algorithms. Our results showed that no one gene had an invariant expression under different conditions. For example, under drought stress, UPL3, UBC2, and APT1 were better reference genes in leaves, RPL5 and FPS2 were better in roots. Under alkali stress, GAPDH, APT1, and RPS5 were better reference genes in leaves; UPL3, ACT2, and SAMDC2 were better in roots. In addition, the expression of MSD1 was used to further confirm the validated reference genes under salt, drought, and alkali stresses. It was proved that the use of inappropriate reference genes in giant reed significantly altered the relative expression of target genes and even reversed the results. Consequently, our results provided guidelines for reference gene selection under salt, drought, and alkali stresses and a foundation for more accurate and widespread use of RT-qPCR in the giant reed.
Project description:<p>The section <em>Oleifera</em> (Theaceae) has attracted attention for the high levels of unsaturated fatty acids found in its seeds. Here, we report the chromosome-scale genome of the sect. <em>Oleifera</em> using diploid wild <em>Camellia lanceoleosa</em> with a final size of 3.00 Gb and an N50 scaffold size of 186.43 Mb. Repetitive sequences accounted for 80.63% and were distributed unevenly across the genome. <em>Camellia lanceoleosa</em> underwent a whole-genome duplication event approximately 65 million years ago (65 Mya), prior to the divergence of <em>C</em>. <em>lanceoleosa</em> and <em>Camellia sinensis</em> (approx. 6-7 Mya). Syntenic comparisons of these two species elucidated the genomic rearrangement, appearing to be driven in part by the activity of transposable elements. The expanded and positively selected genes in <em>C</em>. <em>lanceoleosa</em> were significantly enriched in oil biosynthesis, and the expansion of homomeric <em>acetyl-coenzyme A carboxylase</em> (<em>ACCase</em>) genes and the seed-biased expression of genes encoding heteromeric ACCase, diacylglycerol acyltransferase, glyceraldehyde-3-phosphate dehydrogenase and stearoyl-ACP desaturase could be of primary importance for the high oil and oleic acid content found in <em>C. lanceoleosa</em>. Theanine and catechins were present in the leaves of <em>C</em>. <em>lanceoleosa</em>. However, caffeine can not be dectected in the leaves but was abundant in the seeds and roots. The functional and transcriptional divergence of genes encoding SAM-dependent <em>N</em>-methyltransferases may be associated with caffeine accumulation and distribution. Gene expression profiles, structural composition and chromosomal location suggest that the late-acting self-incompatibility of <em>C. lanceoleosa</em> is likely to have favoured a novel mechanism co-occurring with gametophytic self-incompatibility. This study provides valuable resources for quantitative and qualitative improvements and genome assembly of polyploid plants in sect. <em>Oleifera</em>.</p>