塔里木河下游胡杨空心特征

本文选取塔里木河下游阿拉干断面胡杨林长期监测样地,分析胡杨林空心率、树洞特征及其在不同胸径和树高组间的分布特点。结果表明: 研究区胡杨种群具有较高的空心现象,空心胡杨占调查胡杨总数量的56%,约159株·hm^-2;胡杨空心率在不同胸径和树高组间呈显著差异,其与胸径呈显著正相关,与树高呈显著负相关。该监测样地胡杨树洞密度约560个·hm^-2,平均每株2个;所调查的胡杨树洞大部分出现在树干上(57.1%),均以树干中部洞口为主(31.3%);直径为5~15 cm的树洞(38.2%)所占比例最大。总树洞数量、单株树洞数量、树洞直径等特征与胸径呈显著正相关,与树高呈显著负相关,而各树洞类型在不同胸径和树高组间的分布不同,变化趋势不一致。胡杨树洞在各方位上的分布差异显著,树洞集中分布在正西方向上。胡杨荒漠河岸林的空心发生率较为严重,且胸径越大其空穴化程度越明显。加强保育幼龄胡杨和修复退化荒漠河岸林具有重要意义。     

圈养白头叶猴春季昼夜活动节律

2008 年3 ～5 月,采用瞬时扫描法,对上海动物园5 只白头叶猴的行为进行24 h 昼夜连续观察。结果表明:春季圈养白头叶猴一天的活动起于06∶ 00 左右,结束于18∶ 00 或18∶ 30。白天白头叶猴的主要行为为休息、取食和移动,平均频次依次是13.79 次、4.75 次和2.18 次。夜间的主要行为为休息、移动和抓挠,平均频次依次是22.13 次、0.43 次和0.26 次。不同个体昼夜活动节律差异很大。其中,移动、理毛、玩耍和其它行为的差异显著。夜间无理毛和玩耍行为,移动行为在夜间21∶ 00, 00 ∶ 30, 03∶00 和04∶ 30 出现高峰。在22∶ 30, 01∶ 00, 02∶ 00, 03∶ 30, 04∶ 30 和05∶30 则出现抓挠高峰。这预示白头叶猴夜间休息时处于一个“轻睡眠”状态。同时,雌雄白头叶猴昼夜移动行为差异显著。     

Taxonomic study of Ufens Girault from Xinjiang,China(Hymenoptera: Trichogrammatidae)

The genus Ufens Girault(Hymenoptera: Trichogrammatidae) is reported from Xinjiang, including one newly recorded species for China, U. pallidus Owen, and U. foersteri(Kryger), U. similis(Kryger). Ufensia xinjiangensis Hu Lin is synonymized under U. foersteri. A key to males of six species of Ufens from China is provided. All the specimens examined are deposited in the Insect Collection of College of Life Science and Technology, Xinjiang University, Urumqi, Xinjiang, China(ICXU).     

丰容对圈养雌性岩羊活动时间分配的影响

为了探究环境丰容和食物丰容对岩羊行为和活动节律的影响,于2017年3月—7月,以上海动物园的5只雌性岩羊(Pseudois nayaur)为研究对象,设计环境丰容和食物丰容试验,利用瞬时扫描法对岩羊进行行为学观察,分析岩羊丰容前后昼间行为的变化。结果表明:经过环境丰容,岩羊的运动行为和反刍行为显著增加,卧息行为和其他行为显著减少,取食行为无明显变化。在环境丰容基础上,开展食物丰容后,运动行为明显减少,取食行为明显增加。卧息行为有所减少、反刍行为和其他行为有所增加,但变化均不明显。丰容后岩羊的昼间活动节律也发生了变化。取食行为呈现2个高峰期(8:00—11:00和15:00—18:00),取食行为普遍提高;运动行为在13:30—17:30时段较丰容前提前一个小时左右发生;卧息行为有相似的波动规律,但丰容后其昼间发生频次在16:00之前均降低;反刍行为波动最大,呈现出明显的2个高峰期(6:00—9:00和10:00—15:00)。试验表明,在进行环境和食物丰容后,岩羊的活动增加,优化了时间分配,福利状况得到了有效改善。     

The Microbial Community in the Feces of the Giant Panda (<Emphasis Type="Italic">Ailuropoda melanoleuca</Emphasis>) as Determined by PCR-TGGE Profiling and Clone Library Analysis

Despite having a typical carnivorous digestive tract, the giant panda has a diet consisting exclusively of bamboo, a low-efficiency food source. Given this paradox, we sought to investigate if the giant panda digestive tract is inhabited by organisms indicative of high cellulose diet or their gastrointestinal tract anatomy. The diversity and dynamics of the predominant bacteria in the fecal flora of two adult (male and female) and one young (male) giant panda reared in two different zoos over a 2-year period was studied using 16S rDNA-based approaches. The temperature gradient gel electrophoresis (TGGE) profiles of the 16S rDNA V3 region of the three individuals were highly similar. The structure of their fecal flora remained relatively stable over the 2-year period. Both the most predominant band in TGGE patterns shared by the three pandas and the biggest operational taxonomic unit (OTU) in the clone library were phylogenetically related to Escherichia coli. Gram-negative, facultative bacteria constituted almost 60% of the whole community in the clone library. All the OTUs were related to previously described phylotypes known to reside in the intestine or rumen. The results of our study indicate that the predominant bacterial populations in the intestine of the three pandas were markedly different from that of herbivores. The unbalanced intestinal community structure may play a role in the inefficient digestion of bamboo by the giant pandas.     

玉米叶蝉缨翅缨小蜂Anagrus dmitrievi(膜翅目,缨小蜂科)DNA条形码研究

[目的]玉米叶蝉缨翅缨小蜂Anagrus dmitrievi Triapitsyn&Hu是玉米三点斑叶蝉Zyginidia eremita Zachvatkin卵期的重要寄生性天敌,在玉米三点斑叶蝉生物防治中具有广阔的应用前景.由于该寄生蜂个体微小,通过传统昆虫分类方法难以将其与同类卵寄生蜂准确分类.因此,本研究旨在为玉米叶蝉缨翅缨小蜂的快速准确鉴定提供技术支持.[方法]在室内,采集玉米三点斑叶蝉卯饲养玉米叶蝉缨翅缨小蜂至成虫.根据玉米叶蝉缨翅缨小蜂成虫的体色、触角、翅等形态特征对标本进行鉴定,并利用无损伤法提取样本基因组DNA,通过PCR扩增和测序对COⅠ和ITS2基因进行DNA条形码分子标记试验.[结果]形态学鉴定结果表明饲养获得的寄生蜂标本为玉米叶蝉缨翅缨小蜂.获得了该寄生蜂COⅠ和ITS2的部分序列,相似比对、遗传距离和分子进化树结果表明,玉米叶蝉缨翅缨小蜂COⅠ和ITS2序列分别与NCBI数据库中的同属其他种的相关基因有较高相似性,但存在一定遗传差异,可明显区分.[结论]获得的玉米缨翅缨小蜂的COⅠ和ITS2基因序列可作为玉米叶蝉缨翅缨小蜂的DNA条形码,为后续该寄生蜂的快速准确鉴定提供了分子数据.     

Activity measurement of protein kinase and protein phosphatase by microchip phosphate-affinity electrophoresis

We previously proposed microchip-based phosphate-affinity electrophoresis (μPAE) and demonstrated its application to activity measurement of a tyrosine kinase, c-Src. In this study, we extended the μPAE application to a serine/threonine kinase, protein kinase A (PKA), and to a tyrosine phosphatase, leukocyte antigen-related protein tyrosine phosphatase (LAR PTPase). For standard peptide samples, we obtained linear calibration plots, and the limits of detection were 1.2% (PKA) and 1.5% (LAR PTPase) product peptides in the total peptides. The μPAE was also proven to be effective for unpurified enzyme reaction products.     

Chromosome-scale genomes reveal genomic consequences of inbreeding in the South China tiger: A comparative study with the Amur tiger

The South China tiger (Panthera tigris amoyensis, SCT) is the most critically endangered subspecies of tiger due to functional extinction in the wild. Inbreeding depression is observed among the captive population descended from six wild ancestors, resulting in high juvenile mortality and low reproduction. We assembled and characterized the first SCT genome and an improved Amur tiger (P. t. altaica, AT) genome named AmyTig1.0 and PanTig2.0. The two genomes are the most continuous and comprehensive among any tiger genomes yet reported at the chromosomal level. By using the two genomes and resequencing data of 15 SCT and 13 AT individuals, we investigated the genomic signature of inbreeding depression of the SCT. The results indicated that the effective population size of SCT experienced three phases of decline, ~5.0–1.0 thousand years ago, 100 years ago, and since captive breeding in 1963. We found 43 long runs of homozygosity fragments that were shared by all individuals in the SCT population and covered a total length of 20.63% in the SCT genome. We also detected a large proportion of identical-by-descent segments across the genome in the SCT population, especially on ChrB4. Deleterious nonsynonymous single nucleotide polymorphic sites and loss-of-function mutations were found across genomes with extensive potential influences, despite a proportion of these loads having been purged by inbreeding depression. Our research provides an invaluable resource for the formulation of genetic management policies for the South China tiger such as developing genome-based breeding and genetic rescue strategy.     

Phosphorylation of Rho-associated kinase (Rho-kinase/ROCK/ROK) substrates by protein kinases A and C

Rho-associated kinase (Rho-kinase/ROCK/ROK) is a serine/threonine kinase and plays an important role in various cellular functions. The cAMP-dependent protein kinase (protein kinase A/PKA) and protein kinase C (PKC) are also serine/threonine kinases, and directly and/or indirectly take part in the signal transduction pathways of Rho-kinase. They have similar phosphorylation site motifs, RXXS/T and RXS/T. The purpose of this study was to identify whether sites phosphorylated by Rho-kinase could be targets for PKA and PKC and to find peptide substrates that are specific to Rho-kinase, i.e., with no phosphorylation by PKA and PKC. A total of 18 substrates for Rho-kinase were tested for phosphorylation by PKA and PKC. Twelve of these sites were easily phosphorylated. These results mean that Rho-kinase substrates can be good substrates for PKA and/or PKC. On the other hand, six Rho-kinase substrates showing no or very low phosphorylation efficiency (<20%) for PKA and PKC were identified. Kinetic parameters (K(m) and k(cat)) showed that two of these peptides could be useful as substrates specific to Rho-kinase phosphorylation.     

Convergent Phenotypic Evolution of Rhodopsin for Dim-Light Sensing across Deep-Diving Vertebrates

Rhodopsin comprises an opsin attached to a retinal chromophore and is the only visual pigment conferring dim-light vision in vertebrates. On activation by photons, the retinal group becomes detached from the opsin, which is then inactive until it is recharged. Of all vertebrate species, those that dive face unique visual challenges, experiencing rapid decreases in light level and hunting in near darkness. Here, we combine sequence analyses with functional assays to show that the rhodopsin pigments of four divergent lineages of deep-diving vertebrates have undergone convergent increases in their retinal release rate. We compare gene sequences and detect parallel amino acids between penguins and diving mammals and perform mutagenesis to show that a single critical residue fully explains the observed increases in retinal release rate in both the emperor penguin and beaked whale. At the same time, we find that other shared sites have no significant effect on retinal release, implying that convergence does not always signify adaptive significance. We propose that accelerated retinal release confers rapid rhodopsin recharging, enabling the visual systems of diving species to adjust quickly to changing light levels as they descend through the water column. This contrasts with nocturnal species, where adaptation to darkness has been attributed to slower retinal release rates.