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Computer-aided protein-coding gene prediction in uncharacterized genomic DNA sequences is one of the most important issues of biological signal processing.A modified filter method based on a statistically optimal null filter(SONF) theory is proposed for recognizing protein-coding regions.The square deviation gain(SDG) between the input and output of the model is used to identify the coding regions.The effective SDG amplification model with Class I and Class II enhancement is designed to suppress the non-coding regions.Also,an evaluation algorithm has been used to compare the modified model with most gene prediction methods currently available in terms of sensitivity,specificity and precision.The performance for identification of protein-coding regions has been evaluated at the nucleotide level using benchmark datasets and 91.4%,96%,93.7% were obtained for sensitivity,specificity and precision,respectively.These results suggest that the proposed model is potentially useful in gene finding field,which can help recognize protein-coding regions with higher precision and speed than present algorithms.  相似文献   

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The binding of nuclear proteins prepared from mouse erythroid tissue in different developmental stages to the 5'-flanking regulatory elements of human globin gene, two negative control regions(NCR1, -610 to -490 bp; NCR2,-338 to -233bp), was identified. Two stage specific protein factors corresponding to embryonic and fetal stages were found to be capable of binding to NCR2. These data provided evidence that the cis acting elements of the 5'-flanking region might be involved in the developmental control of globin gene and NCR2 might be responsible in part for the silence of globin gene in the embryonic and fetal stages.  相似文献   

4.
Myostatin is a negative regulator of skeletal muscle mass. The present study cloned the 5′ regulatory region of porcine myostatin gene, screened its polymorphisms and analyzed their associations with early growth traits in Yorkshire pigs. The results indicated that a fragment length polymorphism and a polymorphism concerning two nucleotide changes exist in the 5′ regulatory region of porcine my-ostatin gene. At sites 435 and 447, allele A and allele B have the haplotypes of A-G and G-A, respec-tively. The allelic frequency of B is 0.475 in Yorkshire pigs. No homozygous BB genotype was detected in 9 Laiwu Black pigs. Allele B was found to have positive effect on body weight on day 21 (BW21) (P<0.01), body weight on day 28 (BW28) (P<0.05), body weight on day 70 (BW70) (P<0.05), average daily gain from birth to 21 d (ADG1) (P<0.01), average daily gain from birth to 28 d (ADG2) (P<0.05) and av-erage daily gain from 21 d to 70 d (ADG3) (P<0.01), respectively. The additive effect of allele B on BW21, BW28, BW70, ADG1, ADG2 and ADG3 was 0.596±0.205 kg (P=0.0041), 0.498±0.200 kg (P=0.0136), 1.409±0.551 kg (P=0.0112), 28.39±9.74 g P=0.0041), 17.78±7.15 g (P=0.0136) and 37.00±16.92 g (P=0.0304), respectively, whereas its effect on average daily gain from 28 d to 70 d (ADG4) was not significant (P>0.1), although BB individuals are superior in average daily gain to AA and AB.  相似文献   

5.
A DNA fragment containing consensus sequence of matrix attachment region (MAR) has been isolated from pea genome. Compared with original DNA sequence, one 115 bp-long repeat sequence is deleted in the obtained DNA sequence. DNA fragments located upstream and downstream of repeat DNA sequence respectively share 84% and 93% homology to the corresponding original sequence, and contain A-box or T-box and TATAA sequence, which is characteristics short sequence of MARs. To test the function of the DNA sequence, the plant expression vectors in which β-glucuronidase gene (GUS, uidA) was used as reporter gene were constructed and transferred into tobaccos via Agrobacterium-mediated transformation procedure. Quantitative GUS assay showed that the average level of uidA expression was increased twofold for the presence of MAR, and the highest level of GUS activity of transgenic plants could be increased six times. The results cited above suggest that the isolated DNA sequence contains consensus sequence of MARs and  相似文献   

6.
《菌物学报》2015,(6):1111-1117
采用RAPD-SCAR分子标记技术,从300条RAPD随机引物中筛选到了对条形柄锈菌Puccinia striiformis f.sp.tritici33号生理小种特异的2条引物,将特异性片段回收、克隆和测序后(Gen Bank注册号为AB914691和AB914692),依据其序列设计出了2对引物S261F33/S261R33和S300F33/S300R33,能够特异性地从33号生理小种基因组DNA及发病小麦叶片总DNA中分别扩增出247bp和763bp的片段,其结果与采用常规的鉴别寄主法鉴定的结果一致。因此,这2对引物都可用于条形柄锈菌33号生理小种的快速鉴定与监测。  相似文献   

7.
Number and order of HindⅢ exon-containing fragments (Hd) at 3' region of DMD gene were studied systematically using 16 partly-overlapping cDNA subprobes which were produced from dystrophin cDNA 9- 14 with each of 9 restriction endonudeases. There are 25 Hd fragments corresponding to cDNA 9 -14 in DMD gene. Since then, the exact length and the new order of Hd fragments are established. A new 2.1 kb fragment (Hd 55) is revealed, a 5.2 kb fragment (formely designated as Hd 59) is excluded and the existence of a controversial 3.2 kb fragment (Hd 64) is confirmed. Besides, three new exons were revealed by comparing the PvuⅡ and the XbaⅠ hybridization patterns with the Hindlll hybridization patterns for these cDNA subprobes. It is concluded that there are at least 66 Hd fragments, or 79 exons in DMD gene basing on the discovery of three additional exons. The corresponding relationship between the 66 Hd fragments and the SfiⅠ large scale physical map has been studied, and at least 17 Hd fragments or 19 exo  相似文献   

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赣北冀手类区系调查   总被引:3,自引:1,他引:2  
作者用了7年时间对江西省北部地区进行翼手类调查。共采到20种蝙蝠,全部为江西省的新记录。加上文献记载的1种,这些蝙蝠分隶9属3科。其中菊头蝠科7种,(虫帝)蝠科2种,蝙蝠科12种。本文还报道了对这一地区蝙蝠的区划研究。  相似文献   

10.
Bohaidina(沟鞭藻)古口之新见   总被引:1,自引:0,他引:1  
孙学坤 《古生物学报》1991,30(4):505-510
在光学显微镜及扫描电镜下对采自辽河断陷西部拗陷的61块岩芯样品中的沟鞭藻Bohaidlna进行了观察,在相当数量的化石囊孢上发现了保存较完好的古口。大量标本的仔细观察和比较研究表明,虽然多数Bohaidina的囊孢上不见古口构造,但确有一定数量的囊孢具前间式古口,2a或3I型。对古口的新认识将有可能导致Bohaidina这类囊孢的重新分类。  相似文献   

11.
豌豆肌动蛋白异型体的表达与系统发生分析   总被引:1,自引:0,他引:1  
豌豆(Pisum sativum Linn.)肌动蛋白基因至少可以分为3类异型体: PEAcⅠ、PEAcⅡ和PEAcⅢ,它们的编码区序列相似性很高,而非编码区序列存在显著的差异.RT-PCR和以3′端非翻译区作探针的Southern杂交结果显示豌豆肌动蛋白异型体基因在根、茎、叶、卷须、花粉和幼嫩果实中均表达,但表达强度存在明显差异.利用连续稀释电泳对PEAcⅠ的转录本水平进行分析后发现它倾向于在幼嫩的器官中表达,且在7 d的茎中表达最强;在一个月内的叶片中表达也较强,此后明显下降;卷须中表达变化不显著,在花粉中表达很弱,在幼嫩荚果中的表达亦较多.PEAcⅡ表达特点与PEAcⅠ具有某些相似性.根据肌动蛋白序列重建的系统发生树表明豌豆肌动蛋白3类异型体间的分歧明显,但起源于单、双子叶植物分化前的共同基因祖先.推测豌豆肌动蛋白异型体基因在转录调控和细胞功能上存在差异.  相似文献   

12.
The Mt. Kitanglad Range is one of the country’s important key biodiversity sites;however, information about anuran diversity in this protected area remains depauperate. Herein we provided accounts of anuran species from high-elevation forests, in three sites of the western slope of Mt. Kitanglad range. The combined belt-transect sampling and microha bitat searches accounted for 13 species representing five families. The most represented family was Rhacophoridae with five representative species of the genus Philautus. Twelve out of the 13 species documented in the current survey are endemic. Four previously unaccounted species(Pelophr yne brevipes, Pulchrana grandocula, Sanguirana mearnsi, and Philautus surrufus) were added and brought the total anurans known from Mt. Kitanglad to 26 species. Most of the species were also recorded in forested sites, suggestive of their lesser affinity to non-forested ecosystems. The additional species detected during our survey may also imply that full understanding of anuran diversity of Mt. Kitanglad remains far from complete.  相似文献   

13.
中国人α珠蛋白基因3’HVR多态分布的研究   总被引:2,自引:0,他引:2  
本文以3’HVR为探针,对来自全国17省市的51名无血缘关系的健康人进行P vuⅡ限制性片段长度的多态分析,发现3’HVR在片段大小的变异范围及基因频率的分布均有中国人的特点。结果表明,纯合子占15.7%,杂合子占84 .3%,102个等位基因共有34个长度不同的等位片段,大小从2.0-7.0kb之间呈连续分布, 主要分布在2.0-2.5kb及4.0-6.0kb,频率分别为0.43和0.34。并与刘国仰、余裕炉等的资料进行综合比较,初步揭示了中国人群中3’HVR的多态特点。 Abstract: 51 unrelated Chinese individuals from 17 different provinces and cities were typed for PvuII restiction fragment length polymorphism with the probe 3’HVR.The frequencies of homozygotes and heterozygotes were estimated as 15.7% and 84.3%,34 distinguishable allele sizes showed a continue distribution from 2.0-7.0kb.The main alleles of 2.0-2.5kb and 4.0-6.0kb gave the gene frequencies of 0.43 and 0.34 respectively.The preliminary characteristics of 3’HVR locus in Chinese population were revealed.  相似文献   

14.
宋晓东  江洪    余树全  周国模  常杰  江子山  江波 《生态学报》2008,28(5):1959-1959~1963
叶绿素在植物的生理生态过程中非常重要.利用高光谱数据,揭示光谱反射率上特征光谱与叶绿素含量间的关系将有助于理解叶绿素光谱反射特征的规律.选取了6种亚热带常绿阔叶树种,抽取一定数量的叶片样品,分别测量了叶片的光谱反射率及其叶绿素含量,并建立了光谱反射率曲线上的红边位置附近的光谱反射率和叶绿素总量间的回归模型.结果显示:对所研究的树种而言,红边位置处一窄波长范围内的平均光谱反射率与叶绿素总量间的相关性普遍较高,回归效果显著.从高光谱遥感的角度结合植物的生理生态特点分析了其机理.建立的有关红边位置处的光谱反射率与叶绿素总量间的回归模型普遍具有较高的拟合度,其应用前景较好.  相似文献   

15.
阜平山区草莓错季栽培的生物表现及适宜区域   总被引:1,自引:0,他引:1  
通过田间试验和平行观测气象资料,利用地理信息技术和气候要素计算模型,研究了阜平山区种植草莓的生物表现及适宜种植区域.结果表明:在阜平山区种植草莓能够安全越冬、开花、结果,草莓发育期滞后于河北平原,从而达到错季生产的目的;其草莓品质优良,果实中可溶性固形物和维生素C含量均高于河北平原对应的草莓品种;阜平山区错季草莓的适宜发展区域为海拔900~1 200 m的地区.  相似文献   

16.
太湖河网地区农村非点源氮负荷——以宜兴市大浦镇为例   总被引:1,自引:0,他引:1  
采用野外试验与实地调查相结合,利用泥沙流失方程和GIS平台,定量估算了江苏宜兴市大浦镇农村非点源氮排放负荷.结果表明:大浦镇农村非点源氮排放负荷为207.0 t·a-1,其中农田、生活污水、养殖、垃圾和非农田泥沙流失的排放负荷分别为80.6、61.1、49.3、10.5和5.4 t·a-1,分别占39.0%、29.5%、23.8%、5.1%和2.6%;5种排放源中,农田、生活污水和养殖为优先控制因子;方钱、大浦、浦北和浦南4村平均氮排放负荷为80.4、73.0、60.4和52.3kg·hm-2·a-1,远高于其他区域,为优先控制区.  相似文献   

17.
天山北坡生态经济的脆弱性   总被引:2,自引:0,他引:2  
根据脆弱性的理论内涵,以土地利用变化引起的生态系统服务功能变化为影响力;从资源、经济与社会发展水平三方面选取了14个指标,利用层次分析法、模糊综合评价法确定了社会经济系统的适应能力.在此基础上,应用GIS等手段评价了天山北坡15个市、县生态经济的脆弱性.按级数越大,区域越具有脆弱性的原则,将研究区的生态经济脆弱性划分为5级:一级区为乌苏市和昌吉市;二级区包括呼图壁县、米泉县、阜康市、吉木萨尔县、奇台县和木垒县;三级区为克拉玛依市和乌鲁木齐市:四级区为奎屯市和沙湾县;五级区包括精河县、石河子市和玛纳斯县.生态经济系统脆弱性是区域生态环境变化与社会经济发展的综合反映,脆弱性评估是深化可持续发展理论研究的重要途径.各区域应以降低区域脆弱性为目标,从自身脆弱性影响因素入手制定生态经济协调发展策略,以促进区域的可持续发展.  相似文献   

18.
利用田间试验,研究了桂牧一号杂交象草对不同氮肥水平的响应.结果表明:3个追施氮肥处理株高、分蘖数、干草产量、粗蛋白含量和可溶性糖含量均高于对照处理;高氮追肥处理株高显著高于对照处理,中氮追肥处理分蘖数和干草产量显著高于对照处理,3个追施氮肥处理粗蛋白和可溶性糖年产量显著高于对照处理;追施氮肥有利于促进桂牧一号杂交象草的生长和营养物质的积累;高氮追肥处理的年净收入低于对照处理;中氮追肥处理为最佳经济施肥量,其年净收入显著高于对照处理.  相似文献   

19.
1954—2005年中国北方针叶林分布区的气候变化特征   总被引:3,自引:0,他引:3  
基于中国北方针叶林(兴安落叶松林)分布区8个气象观测站的气象资料,分析了1954—2005年气温和降水的变化特征.结果表明:研究期间,中国北方针叶林分布区的气温以0.38 ℃·(10 a)-1的速度上升,远大于全球近50年来0.13 ℃·(10 a)-1的平均增温速率.尽管夏、秋季的气温呈上升趋势,但不显著;而冬、春季的增温显著(P<0.01);最高年平均气温(0.37 ℃·(10 a)-1)与最低年平均气温(0.54 ℃·(10 a)-1)均呈极显著的增加趋势(P<0.01).降水量年际间波动较大,但没有明显的变化趋势;各季节降水量也没有明显的变化规律,其中春、秋、冬季的降水日数有增加趋势,但没有达到显著水平,而夏季的降水日数呈显著减少趋势(P<0.05);各季降水强度均呈增加趋势,其中夏季(P<0.05)和冬季(P<0.01)的变化达到了显著水平.  相似文献   

20.
内蒙古中部地区土壤金龟子群落特征   总被引:3,自引:2,他引:1  
刘新民 《生态学杂志》2008,27(7):1161-1166
2003-2004年,采用土壤样方法和粪诱捕法调查了内蒙古中部地区7个不同生境中的土壤金龟子群落特征,并以群落系数、欧氏距离、百分率相似系数和因子分析等方法对不同土壤金龟子群落之间的相似性进行了分析.共计捕获土壤金龟子101 788头,分属于7科22属59种.其中,植食性种类3科12属18种,主要为鳃金龟科和丽金龟科的种类;粪食腐食性种类4科10属41种,主要为金龟科、蜉金龟科和粪金龟科的种类.对几种群落相似性聚类分析方法所得结果的对比表明,因子分析方法所得的结果是较为合理的,因子分析排序的结果将7个土壤金龟子群落分为2类:一类为典型草原、草甸草原、荒漠草原和沙地;另一类为农田、退耕地和人工林地.  相似文献   

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