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11.
以马铃薯品种合作88为材料,利用数字基因表达谱(DGE)技术,对–2℃低温胁迫处理后的马铃薯叶片c DNA文库进行差异基因表达谱分析。结果表明,有28 505个基因受低温胁迫诱导差异表达,其中上调表达基因13 703个,下调表达基因14 802个。GO功能显著性富集分析表明,DEGs主要涉及信号生物代谢过程、氧化还原过程、能量代谢、次生代谢过程以及催化活性。KEGG富集分析表明,上调表达基因主要富集于苯丙烷、光合作用天线蛋白、类胡萝卜素的生物合成、苯丙氨酸代谢及淀粉与蔗糖代谢途径,而下调表达基因主要富集于植物激素信号转导途径。利用实时荧光定量PCR(q RT-PCR)验证4个DEGs在低温胁迫条件下的差异表达,其结果与DGE分析结果基本一致,证实了DGE测序结果的可靠性。 相似文献
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利用黑斑病的高抗无性系美洲黑杨I-69及黑斑病的高感无性系欧美杨I-45为材料建立的2个cDNA文库,随机挑取cDNA克隆进行5'端EST序列测序,共获得有效序列20 023条.序列经聚类分析和拼接后,共获得10 816个Unigene,其中包括3 734个Contig,7 082个独立的Singleton.被注释的8 853个具有同源性匹配序列基因中,按照GO的分子功能、生物过程和细胞组分3个不同分类角度进行分类.在具有功能注释的8 853个Unigene中,选出330个与完成全基因组测序的毛果杨序列进行BLAST分析,结果发现有177个抗病相关候选基因出现在282个Unigene中,其中135个分布于杨树的18个不同连锁群上,其他42个基因位于还没定位的scaffolds上.所测定的这些EST序列为后期在基因组水平上研究杨树黑斑病的水平抗性遗传机制及进一步的相关基因发现奠定基础.Abstract: In an attempt to elucidate the molecular mechanism for resistance of black spot disease in poplar,gene expression profiles in leaves of Populus deltoides'Lus'(I-69/55)and P.euramericana'I-45/51',which were inoculated with the pathogen Marssonina brunnea f.sp.brunnea,were analyzed based on expressed sequence tags (ESTs).A total of 20 023 valid ESTs from the 5'terminal ends derived from corresponding cDNA libraries of the two poplar species were sequenced.Cluster analysis of the 20 023 sequences yielded 10 816 tentative unigenes,including 3 734 contigs and 7 082 singletons.All tentative unigenes were classified by Gene Ontology functional categories.To find resistance-associated candidate genes and locate them on poplar genome,330 unigenes was chosen from 8 853 annotated tentative unigenes,and their BLAST alignment was conducted with Populus trichocarpa assembly,1 77 related candidate resistant genes were found,and they presented in 282 unigenes.Among these genes,there were 1 35 genes located on 18 different linkage groups of poplar genome,and 42 genes located on the different scaffolds.This study supplied a resource of candidate genes for further exploring the genetic mechanism for the host horizontal resistance to the pathogen Marssonina brunnea at the whole genome range,and provided important information for further gene discovery. 相似文献
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Hepatozoonosis caused by Hepatozoon canis is an important tick-borne disease of dogs in tropical and sub-tropical regions throughout the world. In the present study evaluation of blood samples collected from 225 dogs presented at Small Animal Clinics, GADVASU, Ludhiana, Punjab (India) was done for the presence of H. canis by PCR based assay targeting a portion of 18S rRNA gene. Of the total samples subjected to PCR, an amplicon of 666 bp was detected in 13.78% samples whereas, routine blood smear examination revealed gamonts in 5.78% samples. Furthermore, prevalence of H. canis infection was found to be significantly associated with season, being highest in summer and lowest in winter while other risk factors e.g. age, sex and breed showed non-significant association. In terms of various clinico-pathological parameters, significant drop in haemoglobin, total red blood cell count, packed cell volume and lymphocytes were recorded in positive cases whereas the total white blood cell count was non-significantly increased. The haematological alterations in the positive cases were lymphopenia, anaemia, thrombocytopenia, relative neutrophilia, neutrophilic leucocytosis, eosinophilia, monocytosis and lymphocytosis while the biochemical profile revealed hypoproteinemia and increased levels of blood urea nitrogen and creatinine (in positive cases) pointing towards renal failure. 相似文献
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[Objective] This study aimed to examine indicative roles of texture representing soil organic carbon presence and variability subsequent to cultivation under cold temperate climates with seasonal freeze-thaw events.[Method] Three chronosequences were selected for paired comparisons.Soil samples were collected at six depths with a 10 cm increment.Analysis of variance with general linear model and regression was performed for statistical analysis.[Result] In seasonally frozen soils where fragmentation of macroaggregates was stimulated,soil organic carbon level was positively associated with clay + silt proportion due to a wider textural range,better than sole clay content.Exponential function better fitted the experimental data to present progressively increased effectiveness of clay + silt content in maintaining carbon.Clay content explained 12%-41% and 14%-43% of variation via linear and exponential functions,respectively.Accordingly,clay + silt content explained 47%-65% and 46%-70%.[Conclusion] Texture reflected soil organic carbon occurrence as consequences of reclamation.For seasonally frozen soils with wider textural ranges,it is robust to adapt clay + silt content as dependent variable and exponential function.The generated algorithms provided an available pathway to estimate soil organic carbon losses following cultivation and to evaluate soil fertility. 相似文献
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Md Shafiqul ISLAM Urara SHINYA Mitsuhiro TAKAGI Takao AKAHOSHI Akira YABUKI Shahnaj PERVIN Tofazzal Md RAKIB Mohammad Mahbubur RAHMAN Martia Rani TACHARINA Osamu YAMATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):254
Bovine isoleucyl-tRNA synthetase (IARS) disorder, a major cause of weak calf syndrome, is caused by a homozygous missense (c.235G>C) mutation in the bovine IARS gene of Japanese Black (JB) cattle, which was identified in 2013. However, the extent to which the carrier rate has changed at Kagoshima prefecture, Japan, and whether the carrier status is associated with any clinical or reproductive problems, have yet to be ascertained. In this study, using a real-time polymerase chain reaction-based genotyping assay, we determined the carrier rate in a regional JB cow population at Kagoshima prefecture. Comparative analyses were performed on the metabolic profile test (MPT) results and reproductive performance data obtained for heterozygous carrier and homozygous wild-type cows. In 2009 and 2018, DNA samples were collected from 130 and 462 clinically healthy JB cows, respectively, in Kagoshima prefecture. MPT results and reproductive performance data were evaluated for 62 cows, comprising four heterozygous carriers and 58 wild-type cows. Genotyping revealed that the carrier rate was 6.9% in 2009 and 1.5% in 2018, the difference of which was statistically significant (P<0.005). There were no statistically significant differences between the carrier and wild-type cows with respect to either MPT results or reproductive performance, indicating that the carrier cows have necessary IARS activity to maintain minimal health and reproductive potential. 相似文献
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Francesco CARUSO Leigh HICKMOTT Joseph D. WARREN Paolo SEGRE Gustavo CHIANG Paulina BAHAMONDE Sonia ESPAÑOL-JIMÉNEZ Songhai LI Alessandro BOCCONCELLI 《Integrative zoology》2021,16(4):594-611
The northern Chilean Patagonia region is a key feeding ground and a nursing habitat in the southern hemisphere for blue whales (Balaenoptera musculus). From 2014 to 2019, during 6 separate research cruises, the dive behavior of 28 individual blue whales was investigated using bio-logging tags (DTAGs), generating ≈190 h of data. Whales dove to significantly greater depths during the day compared to nighttime (day: 32.6 ± 18.7 m; night: 6.2 ± 2.7 m; P < 0.01). During the night, most time was spent close to the surface (86% ± 9.4%; P < 0.01) and at depths of less than 12 m. From 2016 to 2019, active acoustics (scientific echosounders) were used to record prey (euphausiids) density and distribution simultaneously with whale diving data. Tagged whales appeared to perform dives relative to the vertical migration of prey during the day. The association between diurnal prey migration and shallow nighttime dive behavior suggests that blue whales are at increased risk of ship collisions during periods of darkness since the estimated maximum ship draft of vessels operating in the region is also ≈12 m. In recent decades, northern Chilean Patagonia has seen a large increase in marine traffic due to a boom in salmon aquaculture and the passenger ship industry. Vessel strike risks for large whales are likely underestimated in this region. Results reported in this study may be valuable for policy and mitigation decisions regarding conservation of the endangered blue whale. 相似文献