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1.
《遗传学报》2020,47(6):333-336
正Nonhuman primates (NHPs) present significant advantages over rodents for physiological and pharmacological investigations because of their higher genetic and physiological similarity to humans. Both rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) monkeys are considered ideal animal models in biomedical research (Phillips et al., 2014), especially in modeling normal development and diseases in the nervous system (Izpisua Belmonte et al., 2015; Ng et al., 2015; Niu et al., 2015; Poo et al.,  相似文献   

2.
<正>Rapid and efficient isolation of unknown flanking DNA sequences adjacent to known regions is important for molecular biology research.For this purpose,several PCR-based methods have been reported,including inverse PCR(Uchiyama and Watanabe,2006),ligation-mediated PCR(Yan et al.,2003;Ballester et al.,2005;Wang et al.,2007;Trinh et al.,2012)and randomly primed PCR(Liu and Whittier,1995;Liu et al.,1995;Antal et al."2004;Liu and Chen,2007;Reddy et al.,2008;Wang  相似文献   

3.
正As one of the important industrial crops and also an excellent model organism for studying cell elongation,cell wall biosynthesis as well as polyploidy evolution,cotton has always been in the limelight of the world(Shi et al.,2006;Qin and Zhu,2011).With the publication of the allotetraploid Gossypium hirsutum and Gossypium barbadense genomes this year(Li et al.,2015;Zhang et al.,2015;Liu et al.,2015),all three important cotton genomes,including the two ancestor diploid Gossypium raimondii(DD)(Wang et al.,2012;Paterson et al.,2012)and Gossypium arboreum(AA)(Li et al.,2014)have been successfully sequenced by scientists from China and from the United States of America.Since functional studies of Arabidopsis thaliana and  相似文献   

4.
Heterosis,one of the most important biological phenomena,refers to the phenotypic superiority of a hybrid over its genetically diverse parents with respect to many traits such as biomass,growth rate and yield.Despite its successful application in breeding and agronomic production of many crop and animal varieties,the molecular basis of heterosis remains elusive.The classic genetic explanations for heterosis centered on three hypotheses:dominance (Davenport,1908;Bruce,1910;Keeble and Pellew,1910;Jones,1917),overdominance (East,1908;Shull,1908) and epistasis (Powers,1944;Yu et al.,1997).However,these hypotheses are largely conceptual and not connected to molecular principles,and are therefore insufficient to explain the molecular basis of heterosis (Birchler et al.,2003).Recently,many studies have explored the molecular mechanism of heterosis in plants at a genome-wide level.These studies suggest that global differential gene expression between hybrids and parental lines potentially contributes to heterosis in plants (e.g.,Swanson-Wagner et al.,2006;Zhang et al.,2008;Wei et al.,2009;Song et al.,2010).Research suggests that genetic components,including cis-acting elements and trans-acting factors,are critical regulators of differential gene expression in hybrids (Hochholdinger and Hoecker,2007;Springer and Stupar,2007;Zhang et al.,2008).However,other research indicates that epigenetic components,the regulators of chromatin states and genome activity,also have the potential to impact heterosis (e.g.,Ha et al.,2009;He et al.,2010;Groszmann et al.,2011;Barber et al.,2012;Chodavarapu et al.,2012;Greaves et al.,2012a;Shen et al.,2012).  相似文献   

5.
灵长类动物类固醇激素的研究已经在很多物种间展开(Cariso et al.,1999;Lutz et al.,2000;He et al.,2001;Yan and Jiang,2006;Brandon et al.,2008;Lu et al.,2010;Kim et al.,2012)。特别是对于没有明显发情特征的灵长类动物,类固醇激素的变化可以为它们的繁殖状态提供更多可靠的评估(Fujita et al.,2001)。自然状态下野生动  相似文献   

6.
<正>Primary angle closure glaucoma(PACG)is one of the most common causes of irreversible blindness in Asia and about 80%of PACG are present in Asia(Song et al.,2017).Genetics plays an important role in the development of PACG(Gramer et al.,2014).Recently,eight common SNPs were found to be strongly associated with PACG(Vithana et al.,2012;Khor et al.,2016)and mutations in MYRF cause high hyperopia accompanied with PACG(Xiao et al.,2019).However,the genetic defects underlying PACG are still  相似文献   

7.
<正>Auxin plays important roles in various aspects of plant growth and development(Zhao,2010).In Arabidopsis,a number of YUCCA(YUC)genes,which are involved in auxin biosynthesis,have been identified(Zhao et al.,2001;Woodward et al.,2005;Cheng et al.,2006,2007;Kim et al.,2007;Chen et al.,2014).YUC genes encode flavin monooxygenases(FMOs)that convert indole-3-pyruvate(IPA)to indole-3-acetic acid(IAA)(Zhao,2012).The Arabidopsis YUC family is comprised of 11 members(Zhao et al.,2001;  相似文献   

8.
Qi  Hu-Min  Dai  Yue-E  Chen  Wei  Liu  Qian-Qi 《中国科学:生命科学英文版》2019,62(12):1597-1600
<正>Dear Editor,Bisphenol A (BPA), a common and widely used monomer in the production of polycarbonate plastics and epoxy resin,(Healy et al., 2015; De Filippis et al., 2018) has been defined as an endocrine disrupting chemical (EDC) associated with the etiology of insulin resistance (IR)(Gioiosa et al., 2015;Wei et al., 2017) and metabolic disorders (Padmanabhan et al., 2010; Fang et al., 2015; Balistrieri et al., 2018). However,  相似文献   

9.
Dear Editor, Many forms of sight-threatening diseases, including retinitis pigmentosa (RP) and age-related macular degeneration (AMD), are caused by the dysfunction, degeneration and loss of the retinal pigment epithelium (RPE)(Strauss, 2005). RPE cell transplantation may potentially recover or halt disease progression, in which human embryonic stem cells (hESCs) could serve as an unlimited donor source for RPE differentiation, and a few clinical trials have shown the safety and effective of transplantation of hESCs-derived RPE (hESC-RPE) for AMD patients (Schwartz et al., 2012;Schwartz etal., 2015;Song etal., 2015;da Cruz et al., 2018;Kashani et al., 2018;Liu et al., 2018).  相似文献   

10.
<正>Grain shape is a key breeding target that influences both grain yield and appearance quality in rice. Breeding for long-slender grains is an effective strategy to improve grain quality (Jain et al., 2004;Wang et al., 2012, 2015a). In the past two decades, several quantitative trait loci (QTLs) responsible for grain size and shape have been identified, including GS3 (Fan et al., 2006), GS5 (Li et al., 2011),  相似文献   

11.
The influence of rainfall on the foraging patterns of Great Tit Parus major parents while feeding chicks at the nest was investigated using automated nest monitoring with electronic balances and photography. Great Tit females significantly reduced their visit rate to the nest during all rain intensities, while male feeding frequency did not significantly change. The female response was probably due to increased brooding requirements of young since the reduction in visit rate was most apparent at early nestling stages. At this time the chicks are incapable of thermoregulation and females significantly increased their nestbox occupancy time during rain. There was no indication that parents were compensating for periods of female inactivity during rainfall: there was no significant increase in visit rate following rainfall and no significant increase in prey size delivered to the nest during periods of rain. An analysis of data from six consecutive years revealed that the proportion of wet hours within the first week of the nestling period significantly influenced fledging weight in this species.  相似文献   

12.
温带地区分布的灵长类动物在食物匮乏的时候容易受到食物不足的胁迫。川金丝猴就是分布于温带区域的灵长类动物之一,因此在不同的季节,食物对其有不同程度的影响。神农架自然保护区是川金丝猴分布的最东缘,该地区的研究对川金丝猴的保护有着非常重要的影响。本文通过对神农架川金丝猴食源植物和栖息环境 的植被调查,来探讨食物的分布和丰富程度对川金丝猴的影响。在神农架川金丝猴分布的核心地区,选择具有代表性的植被类型,按照海拔梯度设置88个样方,基于优势树种和数据分析,我们把川金丝猴的栖息地划分为12 个类型。阔叶林的食源植物种类要高于针阔混交林;而低海拔的类型中提供食源植物的种类要高于高海拔类型。尽管川金丝猴的食谱范围很广,但是它喜食的食物种类分布极不均匀,而且在其不同类型的栖息地内,食源植物的种类和数量随着季节的变化而变化。因此,季节的变化和食源植物的分布不均衡都会影响川金丝猴的取食行为和时间分配。我们建议借助人为改造森林结构,增加食源植物的数量,进而达到保护和扩大川金丝猴种群的目的。  相似文献   

13.
Anthropogenic landscapes can be rich in resources, and may in some cases provide potential habitat for species whose natural habitat has declined. We used remote videography to assess whether reintroducing individuals of the threatened New Zealand falcon Falco novaeseelandiae into a highly modified agricultural habitat affected the feeding rates of breeding falcons or related breeding behavior such as nest attendance and brooding rates. Over 2,800 recording hours of footage were used to compare the behavior of falcons living in six natural nests (in unmanaged, hilly terrain between 4 km and 20 km from the nearest vineyard), with that of four breeding falcon pairs that had been transported into vineyards and nested within 500 m of the nearest vineyard. Falcons in vineyard nests had higher feeding rates, higher nest attendance, and higher brooding rates. As chick age increased, parents in vineyard nests fed chicks a greater amount of total prey and larger prey items on average than did parents in hill nests. Parents with larger broods brought in larger prey items and a greater total sum of prey biomass. Nevertheless, chicks in nests containing siblings received less daily biomass per individual than single chicks. Some of these results can be attributed to the supplementary feeding of falcons in vineyards. However, even after removing supplementary food from our analysis, falcons in vineyards still fed larger prey items to chicks than did parents in hill nests, suggesting that the anthropogenic habitat may be a viable source of quality food. Although agricultural regions globally are rarely associated with raptor conservation, these results suggest that translocating New Zealand falcons into vineyards has potential for the conservation of this species.  相似文献   

14.
We analysed video-sequences of undisturbed parental provisioning behaviour on 12 nests of common redstart (Phoenicurus phoenicurus). In 4 of the 12 nests, chicks were fed by a single parent only. We compared provisioning rate of chicks, time spent on the nest and food allocation rules between nests with uniparental and biparental care and between male and female parents in biparental nests. In nests with a single parent, the frequency of feeding visits per parent was higher than in biparental nests. As a result, the rate of food provisioning of chicks was similar in uniparental and biparental nests. The food allocation rules did not differ between uniparental and biparental nests. In biparental nests, male and female provisioning behaviour was similar though with two exceptions: males had a strong preference for feeding chicks in front positions in the nest and females spent a longer time on the nest after feeding. We conclude that single common redstart parents are able to compensate fully for the absence of the other parent through increased provisioning efforts, and that in biparental nests, males and females contribute equally to the provisioning of the young.  相似文献   

15.
To explain the adaptive significance of sex role partitioning and reversed sexual size dimorphism among raptors, owls and skuas, where females are usually larger than males, we combine several previous hypotheses with some new ideas. Owing to their structural and behavioural adaptations for prey capture, predatory birds have better prospects than other birds of defending their offspring against nest predators. This makes sex role partitioning advantageous; one parent guards the offspring while the other forages for the family. Further, among predators hunting alert prey such as vertebrates, two mates because of interference may not procur much more food than would one mate hunting alone. By contrast, two mates feeding on less alert prey may together obtain almost twice as much food as one mate hunting alone. For these reasons, partitioning of breeding labours might be adaptive only in predatory birds. An initial imbalance favours female nest guarding and male foraging: the developing eggs might be damaged if the female attacks prey; their mass might reduce her flight performance; she must visit the nest to lay; and the male feeds her before she lays (‘courtship feeding’). Increased female body size should enhance egg production, incubation, ability to tear apart prey for the young, and, in particular, offspring protection in predatory birds. Efficient foraging during the breeding period then becomes most important for the male. This imposes great demands on aerial agility in males, particularly among predators of agile prey. Flight performance decreases with increasing size in five of six aspects explored. The male must therefore not be too large in relation to the most important prey. For these reasons, he should be smaller than the female. Among predatory birds, size dimorphism increases with the proportion of birds in the diet, which may be explained as follows. Adult birds have mainly one type of predators: other predatory birds. Because almost only these specialists exploit adult birds, they carry out most of the cropping of this prey. A predator of easier prey competes with many other kinds of predators, which considerably reduce prey abundance in its territory. This is not so for predators of adult birds. Further, because birds are extremely agile, the specialized predator can hunt efficiently only within a limited size range of birds, whose flight skill it can match. Increased size dimorphism among these predators therefore should be particularly important for enlarging the combined food base of the pair. A bird specialist may consume much of the available prey in the suitable size range during the breeding period. When the predator's young are large enough to defend themselves, the female aids better by hunting than by guarding the chicks. It is advantageous among bird specialists if she hunts prey of other sizes than does the male, who has by then reduced prey abundance in his prey size class. But among predatory birds hunting easier prey the female gains little by hunting outside the male's prey spectrum, because other kinds of predators will have reduced the prey abundance outside as well as inside the male's preferred size range. Intra-pair food separation through large sexual size dimorphism therefore should be particularly advantageous among predators of birds. This may be the main reason why the degree of size dimorphism increases with the dietary proportion of birds.  相似文献   

16.
Predation may reduce prey numbers in such extent that prey may be depleted, which has negative effects on predator populations. Prey depletion would be more likely when the number of predators increase and/or concentrate their activity in a certain area, as is the case of colonial birds. As a matter of fact, food depletion due to intraspecific competition is considered a major cost of coloniality, and several studies have shown indirect evidence of this. However, no direct measures of food depletion have been provided along with its consequences for the fitness of the colony inhabitants. We carried out a field study with the lesser kestrel Falco naumanni, a raptor that breeds in colonies ranging from two to dozens of pairs. During the nestling period we sampled the main prey of the kestrels around different sized colonies at increasing distances. At the same time, we recorded hunting distances and prey delivery rates to the nest. In addition, we monitored the reproductive success in colonies of different sizes. Lesser kestrels feed their nestlings mainly with grasshoppers and these prey became depleted through the season in the surroundings of the large colonies. Prey depletion made kestrels fly longer distances to forage and prey delivery rates to the nest decreased. Lower feeding rates were not compensated by bringing larger prey, hence, the net amount of energy provided to the chicks decreased with the date in large colonies. By contrast, none of this occurred around small colonies, where both prey abundance and hunting distance remained constant throughout the season. As a consequence, the seasonal decline in the reproductive success (number of fledglings and fledgling body condition) was greater the larger the colony. Thus, these results evidence that food depletion and its fitness costs are related to colony size, as they are suffered by the kestrels breeding in large colonies but not by those settled at small ones. Finally, the consequences of prey depletion on the demographic dynamics and the regulation of colony size are discussed.  相似文献   

17.
Obligate avian brood parasitism typically involves one of 2strategies: parasite chicks are either 1) virulent and evictall other eggs and nest mates to be raised alone or 2) moretolerant and share foster parental care with host chicks forsome or the entirety of the nestling period. We studied theconsequences of experimentally forced mixed broods of age-matchedone common cuckoo (Cuculus canorus) and 2 great reed warbler(Acrocephalus arundinaceus) chicks. In these broods, both cuckooand host chicks grew slower than did either individual cuckoosor great reed warblers in broods of 1 parasite or 3 host chicks,respectively. Video records showed that in mixed broods, cuckoochicks received feedings less frequently than the 33% predictedby chance at 4 days of age but parental food allocations increasedto chance levels at 8 days of age. The consistent patterns oflower growth rates arose even though chicks in broods of 1 parasiteand 2 hosts received the largest prey items per feeding. Inaddition, several other measures of parental provisioning alsodid not predict species and brood-specific differences in nestlinggrowth rates across the different treatments. However, variationin begging displays and its specific costs on host and parasitechicks in the different nest treatments were not quantifiedin this study. We conclude that young of nest mate–evictorcommon cuckoos benefit from the sole occupancy of host nestsin part owing to an initial competitive disadvantage for parentalcare in broods with age-matched great reed warbler chicks.  相似文献   

18.
Fennoscandian alpine tundra habitats support large numbers of breeding waders, but relatively little is known about their breeding ecology despite the fact that this habitat is threatened by climate change. We studied habitat selection, diet and prey availability of European (Eurasian) Golden Plover Pluvialis apricaria chicks at the Vindelfjällen Nature Reserve, Ammarnäs, Sweden. Information from 22 chicks tracked using radio‐transmitters was analysed. By analysing 149 faecal samples, four main prey taxa were identified, Coleoptera (40%), Bibionidae (31%), Hymenoptera (13%) and Tipulidae (10%). We found that chicks switched from feeding on Tipulidae to feeding on Bibionidae as they grew, and that this switch coincided with a shift from the use of the habitat where Tipulidae were abundant (alpine meadow/heathland) to the use of the habitat were Bibionidae were abundant (Willow shrub). Although chicks track food availability to some extent, the link between prey availability and habitat use was not perfect, indicating that additional factors other than food abundance, such as shelter from predators, determine habitat selection. Bibionidae are an important prey for Golden Plover chicks as it is the only prey group that has a late summer flush in abundance, in contrast to the general decline of total arthropod biomass during the chick‐rearing period. However, Bibionidae imagoes only occurred in 2011 and were virtually absent in 2013, which relates to the species’ ecology with 2‐ to 5‐year cycles in mass occurrence. Extreme annual variation in an essential food source such as Bibionidae imagoes might have an important effect on the condition and survival of Golden Plover chicks, an important subject for future studies. The foraging conditions for Golden Plover chicks in Fennoscandia appear to be different to those in the UK, where the chicks rely mainly on a Tipulidae flush only.  相似文献   

19.
Chick begging as a signal: are nestlings honest?   总被引:7,自引:3,他引:4  
Begging by dependent avian offspring is known to correlate withhunger level, and parents use this as a signal of brood demandto adjust their chick feeding behavior. While there is informationon how each chick adjusts its begging to its own condition,little is known of how chicks adjust to the state of their nestmates. In two experiments we manipulated the competitive environmentof individual European starling (Sturnus vulgaris) chicks byaltering the state of nest mates while holding the state oftarget chicks constant In the first experiment we placed thetarget chick's nest mates in neighboring nests with brood sizesof two, five, or eight chicks. Following the manipulation wereturned them to their own nests and recorded begging behavioron videotape. In the second experiment we separated a targetchick from its siblings and manipulated feeding level in thelaboratory. The siblings were fed at one of three levels; meanwhile,all the target chicks were fed at the intermediate level. Afterthe manipulation we placed the target chicks with their siblingsand recorded their begging in response to an artificial stimulus.In neither experiment was the begging effort of the unmanipulatedtarget chicks affected by the changes in begging behavior oftheir siblings. This result supports the view that begging isa reliable signal of individual chick state and does not involveresponses to the effort of nest mates.  相似文献   

20.
In birds with bi-parental care, the provisioning link between prey capture and delivery to dependent offspring is regarded as often symmetric between the mates. However, in raptors, the larger female usually broods and feeds the nestlings, while the smaller male provides food for the family, assisted by the female in the latter part of the nestling period, if at all. Prey items are relatively large and often impossible for nestlings to handle without extended maternal assistance. We video-recorded prey delivery and handling in nests of a raptor with a wide diet, the Eurasian kestrel Falco tinnunculus, and simultaneously observed prey transfer from male to female outside the nest. The male selectively allocated larger items, in particular birds and larger mammals, to the female for further processing and feeding of nestlings, and smaller items, in particular lizards and smaller mammals, directly to the nestlings for unassisted feeding. Hence, from the video, the female appeared to have captured larger prey than the male, while in reality no difference existed. The female’s size-biased interception of the male’s prey provisioning line would maximize the male’s foraging time, and maximize the female’s control of the allocation of food between her own need and that of the offspring. The male would maximize his control of food allocation by capturing smaller prey. This conflict would select for larger dominant females and smaller energy-efficient males, and induce stronger selection the longer the female depends on the male for self-feeding, as a proportion of the offspring dependence period.  相似文献   

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