使用SPE软件筛选绿尾虹雉微卫星引物及其在亲缘关系鉴定上的应用

圈养绿尾虹雉Lophophorus lhuysii多为一雄配多雌,但由于雄鸟更换,雌鸟产蛋期交错,且无特定产蛋位,导致亲子关系难以确认。本研究从绿尾虹雉基因组中广泛筛选微卫星位点,得到13对引物。采用微卫星PCR引物特异性鉴定程序（SPE）对引物序列进行评估,排除1例PCR产物长度相近的特殊多位点扩增。利用获得的12个微卫星标记在18份绿尾虹雉蛋壳/羽毛DNA样品中进行遗传多样性分析,同时以其中15份蛋壳样品（2018—2019年搜集）为检材,进行了亲缘（同胞）关系鉴定。结果表明,这12个微卫星标记可用于绿尾虹雉亲缘关系的鉴定,对提高小种群的维持能力,保持种群遗传多样性具有重要意义。     

勐养保护区亚洲象微卫星位点筛选及种群遗传多样性分析

本文以亚洲象肌肉样品提出的DNA为模板,从非洲象31个微卫星位点和5个已知亚洲象微卫星位点中筛选勐养亚洲象的微卫星位点,进而对在西双版纳勐养保护区3年采集到的191 份亚洲象粪便样品中提出的DNA进行特异性PCR扩增、基因分型、检测位点信息和遗传多样性分析.结果表明:36个位点中有14个位点能在亚洲象肌肉样品提出的DNA中成功扩增,且经测序证实为微卫星位点.其中9个多态位点能在185份粪便样品DNA中稳定扩增.勐养种群中,3个位点可能偏离Hardy Weubberg平衡,至少8个位点间无明显连锁存在,平均等位基因数3.78±1.72,平均期望杂和度0.32 ± 0.06,平均观察杂和度0.36±0.02,平均多态信息含量0.28 ,说明这9个位点适用于勐养亚洲象的遗传学研究.根据微卫星位点的杂合度和等位基因频率,相比于其他亚洲象种群,勐养亚洲象种群遗传多样性较低且等位基因频率具有特异性.     

梨小食心虫微卫星标记的扩增稳定性及多态性分析

【目的】筛选适合我国梨小食心虫Grapholita molesta种群遗传学研究的微卫星位点,并依据所筛选的微卫星位点进行梨小食心虫地理种群的遗传多样性分析。【方法】利用欧洲梨小食心虫和苹果蠹蛾Cydia pomonella种群中已报道的11个微卫星位点, 分析各位点在我国12个种群257头梨小食心虫样本中的扩增稳定性,再进行其多态性分析,筛选适合的位点,然后进行种群遗传多态性分析。【结果】在分析的11个微卫星位点中, 位点Gm01, Gm03, Gm04和Cyd15无法稳定扩增; 位点Gm05扩增成功率较低, 位点Gm07遗传多态性较低; 而位点Gm02, Gm06, Gm08, Gm09和Gm10等扩增效果稳定且遗传多态性丰富。这5个稳定扩增的微卫星位点平均等位基因数量（N_A）为7.417~12.500, 平均观察杂合度（H_o）为0.366~0.655, 平均期望杂合度（H_e）为0.642~0.846, 多态信息含量（PIC）为0.800~0.935。【结论】本研究成功筛选出位点Gm02, Gm06, Gm08, Gm09和Gm10等5个微卫星位点。基于这5个微卫星位点标记的结果显示, 山东和陕西不同梨小食心虫地理种群均具有丰富的遗传多样性。 这5个位点可以适用于我国梨小食心虫种群的进一步遗传分析研究。     

TRAP及SSCP检测草鱼微卫星序列多态性

目的：在草鱼不同种群遗传结构比较中,应用一些来自鲤鱼的微卫星引物扩增草鱼的相关序列缺少多态性,该研究通过应用几种方法提高这些序列在遗传学研究中的价值。方法：运用TRAP随机引物与鲤鱼的微卫星引物组合,扩增出多态性好、重复性强的产物;同时采用SSCP技术对那些没有长度多态的微卫星序列进一步分析,寻找这些序列存在一些核苷酸位点的多态性。结果：TRAP可以检查到多态性好、重复性强的产物;SSCP发现一部分没有长度多态性的微卫星序列存在核苷酸位点多态性并且可以清楚分辨不同的基因型。结论：结果表明TRAP及SSCP在种群遗传学研究有良好的应用前景。     

树鼩微卫星DNA的多态性研究

目的探索并建立一种检测树鼩群体遗传多样性的方法。方法利用聚合酶链反应（PCR）扩增技术对30只树鼩个体的11个微卫星位点进行了遗传检测。结果所选的11个微卫星DNA位点中,有9个具有高度多态性,2个微卫星DNA位点多态性较差。结论所研究的树鼩微卫星位点中,有9个符合遗传标记特点,可用于检测树鼩群体的遗传多样性。     

微卫星跨物种交叉PCR扩增的一个新问题:扩增非同源产物

微卫星已被广泛应用于群体遗传学、生态学和进化生物学研究。然而,一些物种微卫星尚未克隆。为了节省时间和经费,研究人员往往使用一个物种已发表的微卫星引物扩增其近缘物种的微卫星。该研究对属于3个不同科(Clariidae、Heteropneustidae 和Pimelodidae)的7个鲶鱼物种的微卫星跨物种PCR扩增产物进行了序列分析,研究发现扩增非同源（non-orthologous）产物是微卫星跨物种PCR扩增的一个新问题。该研究共采用4对胡子鲶微卫星座位引物对7个鲶鱼物种进行了跨物种PCR扩增。对获得的204个PCR产物的序列分析结果表明,两对微卫星座位引物扩增了所有7个物种的同源特异产物。而其他两个座位的引物扩增了特异但非同源的多态产物,对近缘物种的扩增也获得类似结果。另外,除胡子鲶等位基因大小异源同型(size homoplasy)的特征不明显外,其他物种在3个微卫星座位都具有这一非常明显的特征。这些数据表明,微卫星跨物种间交叉扩增能产生非同源产物;等位基因大小异源同型与微卫星座位本身有关,而与物种间的亲缘关系无明显的相关性。微卫星跨物种扩增产生的非同源产物和等位基因大小异源同型将使系统发育、群体遗传学和进化研究明显复杂化。因此,在应用微卫星跨物种交叉扩增数据以前,最好对跨物种交叉扩增产物进行测序验证。     

大鼠及小鼠微卫星引物在社鼠中的跨种扩增

利用微卫星引物在同一属、科、目不同种之间具有通用性的特点,通过PCR扩增、聚丙烯凝胶电泳和银染技术对社鼠(Niviventer confucianus)近缘物种大鼠(Rattus norvegicus)、小鼠(Mus musculus)中已知的70个微卫星位点引物进行跨种扩增,筛选适合社鼠相关研究的多态微卫星引物.结果发现,40个位点引物出现扩增条带,21个位点引物能够稳定扩增,其中15个位点杂合,13个位点具有多态性;PCR扩增的Mg2+浓度主要集中在1.5及2.0 mmol/L,退火温度在50～60℃之间不等.虽然部分扩增产物有影子带的存在,但并不影响等位基因的判读.总体来看,利用大、小鼠的微卫星引物扩增社鼠的微卫星位点是可行的.     

鲤科鱼蓝黑鲮微卫星位点的种间扩增(英文)

本研究使用105对微卫星引物对7种鲤科鱼类进行跨越种间PCR扩增,共得到14个多态性微卫星位点.其中9个扩增效果较好的位点用于分析来自帕吉勒提河(Bhagirathi, n=20)和戈达瓦里河(Godavari, n=25)的蓝黑鲮(Labeo calbasu)样品的遗传多样性.结果显示,前者在每个位点的平均等位基因数为7.33,而后者为8 1,期望杂合度介于0.795(Bhagirathi)和0.801(Godavari)之间;4个位点MFW11* (Godavari)、R1*(Godavari)、R3* (Bhagirathi) 和 Lr38*(Bhagirathi和Godavari)都表现出明显的杂合子缺失和哈迪温伯格平衡偏离;而任意两位点间都未观测到连锁不平衡现象;位点R3*极可能存在无效等位基因.上述结果表明这些多态性微卫星位点作为共显性标记在蓝黑鲮群体遗传学研究中有着较好的应用前景.     

微卫星遗传标记及其在昆虫种群遗传学中的应用

微卫星是一类短串联重复的寡核苷酸序列,广泛地分散于各类真核生物基因组中,它具有多态性高、检测结果稳定可靠等特点,是目前较为理想的群体遗传研究的分子标记之一。该文阐述了微卫星DNA构成及特点,多态性形成机制、位点获得途径,列举了微卫星遗传标记在昆虫种群遗传学研究中的应用实例,并展望了该技术的应用前景。     

微卫星多态性检测技术及其在保护遗传学中的应用

微卫星是一种新型的分子遗传标记,具有只需极少量样品即可进行PCR扩增等优点,使之极其适合于保护遗传化学研究。阐释了微卫星的结构、微卫星多态检测技术的原理,简要论述了微卫生多态检测技术的优点及其应用,并介绍了一种分离动物微卫星位点的富集方法。     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

Changes in lactate dehydrogenase activity in chicken tissues in hyperthyreosis in ontogenesis

The lactate dehydrogenase activity in reactions of lactate oxidation and synthesis was studied in subfractions of the chicken brain, heart and liver at the embryonal, early postembryonal and adult stages of development after thyroxine administration. It has been shown that during embryogenesis thyroxine predominantly enhanced the rate of lactate oxidation in the mitochondrial tissues. A marked increase in the lactate synthesis was found in cytoplasm of the adult chicken tissues. Specificity of enzyme activity alterations was detected in the chicken brain during ontogenesis after thyroxine administration.     

Scurvy in capybaras bred in captivity in Argentine

In order to determine if the absence of vitamin C in the diet of capybaras (Hydrochoerus hydrochaeris) causes scurvy, a group of seven young individuals were fed food pellets without ascorbic acid, while another group of eight individuals received the same food with 1 g of ascorbic acid per animal per day. Animals in the first group developed signs of scurvy-like gingivitis, breaking of the incisors and death of one animal. Clinical signs appeared between 25 and 104 days from the beginning of the trial in all individuals. Growth rates of individuals deprived of vitamin C was considerably less than those observed in the control group. Deficiency of ascorbic acid had a severe effect on reproduction of another population of captive capybaras. We found that the decrease in ascorbic acid content in the diet affected pregnancy, especially during the first stages. The results obtained suggest that it is necessary to supply a suitable quantity of vitamin C in the diet of this species in captivity.     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.