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21.
The complete nucleotide sequence of the mitochondrial genome of the cabbage butterfly,Artogeia melete (Lepidoptera: Pieridae) 总被引:3,自引:0,他引:3
Guiyun Hong ;Shaotong Jiang ;Miao Yu ;Ying Yang ;Feng Li ;Fangsen Xue ;Zhaojun Wei 《Acta biochimica et biophysica Sinica》2009,(6):446-455
The complete mitochondrial genome (mitogenome) of Artogeia melete was determined as being composed of 15,140 bp, including 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and one control region. The gene order of A. melete mitogenome is typical of Lepidoptera and differs from the insect ancestral type in the location of trnM. The A. melete mitogenome has a total of 119 bp of intergenic spacer sequences spread over 10 regions, ranging in sizes between 1 and 48 bp. The nucleotide composition of the A. melete mitogenome is also biased toward A + T nucleotides (79.77%), which is higher than that of Ochrogaster lunifer (77.84%), but lower than nine other lepidopterans sequenced. The PCGs have typical mitochondrial start codons, except for coxl, which contains the unusual CGA. The coxl, cox2, nad2, and nad5 genes of the A. melete mitogenome have incomplete stop codons (T). The A. melete A + T-rich region contains some conserved structures that are similar to those found in other lepidopteran mitogenomes, including a structure combining the motif ‘ATAGA', a 19-bp poly(T) stretch, a microsatellite (AT)n element, and a 9-bp poly(A) upstream trnM. The A. melete mitogenome contains a duplicated 36-bp repeat element, which consists of a 26- bp core sequence flanked by 10-bp perfectly inverted repeats. 相似文献
22.
Drought stress has long been a major constraint in maintaining yield stability of soybean (Glycine max (L.) Merr.) in rainfed ecosystems. The identification of consistent quantitative trait loci (QTL) involving seed yield per plant (YP) and drought susceptibility index (DSI) in a population across different environments would therefore be important in molecular marker-assisted breeding of soybean cultivars suitable for rainfed regions. The YP of a recombinant line population of 184 F2:7:11 lines from a cross of Kefengl and Nannong1138-2 was studied under water-stressed (WS) and well-watered (WW) conditions in field (F) and greenhouse (G) trials, and DSI for yield was calculated in two trials. Nineteen QTLs associated with YP-WS and YP-WW, and 10 QTLs associated with DSI, were identi- fied. Comparison of these QTL locations with previous findings showed that the majority of these regions control one or more traits re- lated to yield and other agronomic traits. One QTL on molecular linkage group (MLG) K for YP-F, and two QTLs on MLG C2 for YP-G, remained constant across different water regimes. The regions on MLG C2 for YP-WW-F and MLG H for YP-WS-F had a pleiotropic effect on DSI-F, and MLG A1 for YP-WS-G had a pleiotropic effect on DSI-G. The identification of consistent QTLs for YP and DSI across different environments will significantly improve the efficiency of selecting for drought tolerance in soybean. 相似文献
23.
MYS2多态位点在中国26个人群中分布的研究 总被引:2,自引:0,他引:2
对中国26个人群中Y染色体小卫星分位点MYS2的分布进行了研究,结果显示:MYS2*4是常见的等位基因类型,MYS2*3在中国不同人群中分布差异很大(0-32.4%);并对该位点在不同人群中分布的频率进行了AMOVA分析,结果为:不分组、南方人群和北方人群的遗传学差异分别为7.76%、8.11%和1.42%。南北方人群间、东北和西北人群间的差异分别为4.34%和1.57%。结论:MYS2是研究中国人群遗传结构有价值的多态位点,中国不同人群之间存在一定的遗传学差异,中国南方人群间的遗传学差异较大,再次证实了中国人群的南北差异。 相似文献
24.
HENG CHUAN XIA FENG LI ZHEN LI Zu CHUAN ZHANG~* Key Laboratory of Proteomics Institute of Biochemistry Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China. 《Cell research》2003,(5)
A novel ribosome-inactivating protein designated Moschatin from the mature seeds of pumpkin (Cucurbita moschata) has been successively purified to homogeneity, using ammonium sulfate precipitation, CM-cellulose 52 column chromatography, Blue Sepharose CL-6B Affinity column chromatography and FPLC size-exclusion column chromatography. Moschatin is a type 1 RIP with a pI of 9.4 and molecular weight of~29 kD. It is a rRNA N-glycosidase and potently blocked the protein synthesis in the rabbit reticulocyte lysate with a IC_(50) of 0.26 nM. Using the anti-human melanoma McAb Ng76, a novel immunotoxin Moschatin-Ng76 was prepared successfully and it efficiently inhibited the growth of targeted melanoma cells M_(21) with a IC_(50) of 0.04 nM, 1500 times lower than that of free Moschatin. The results implied that Moschatin could be used as a new potential anticancer agent. 相似文献
25.
Qing-Shan Chang Rong-Hua Zhou Xiu-Ying Kong Zeng-Liang Yu Ji-Zeng Jia 《植物学报(英文版)》2006,48(11):1348-1354
Talgu Genlc Male Sterile Wheat (TGMSW; Trltlcum aestlvum L.), a dominant genic male sterile germplasm, is of considerable value in the genetic Improvement of wheat because of Its stable Inherence, complete male abortion, and high cross-fertilization rate. To Identify specially transcribed genes In sterile anther, a suppression subtractlve hybridization (aSH) library was constructed with sterile anther as the tester and fertile anther as the driver. A total of 2 304 SSH Inserts amplified by polymerase chain reaction were arrayed using robotic printing. The cDNA arrays were hybridized with 32P-labeled probes prepared from the RNA of forward- and reverse-subtracted anthers. Ninety-six clones were scored as upregulated in sterile anthers compared with the corresponding fertile anthers and some clones were selected for sequencing and analysis In GenBank. Based on their putative functions, 87 non-redundant clones were classified Into the following groups: (i) eight genes Involved In metabolic processes; (11) four material transportation genes; (iii) three signal transductlon-assoclated genes; (iv) four stress response and senescence-associated protein genes; (v) seven other functional protein genes; (vi) five genes with no known function; and (vii) another 56 genes with no match to the databases. To test the hybridization efficiency, eight genes were selected and analyzed by Northern blot. The results of the present study provide a comprehensive overview of the genes and gene products Involved In anther abortion In TGMSW. 相似文献
26.
Screening for High-Temperature Tolerant Cotton Cultivars by Testing In Vitro Pollen Germination, Pollen Tube Growth and Boll Retention 总被引:5,自引:0,他引:5
Zhi Liu You-Lu Yuan Shao-Qing Liu Xiao-Nan Yu Li-Qun Rao 《植物学报(英文版)》2006,48(6):706-714
With radical global climate change and global warming, high temperature stress has become one of major factors exerting a major influence on crop production. In the cotton (Gossypium hirsutum L.)-growing areas of China, especially in the Yangtze River valley, unexpected periodic episodes of extreme heat stress usually occur in July and August, the peak time of cotton flowering and boll loading, resulting in lower boll set and lint yield. Breeding programs for screening high temperature-tolerant cotton germplasm and cultivars are urgent in order to stabilize yield in the current and future warmer weather conditions. In the present study, 14 cotton cultivars were quantified for in vitro pollen germination and pollen tube growth in response to temperatures ranging from 10 to 50 ℃ at 5 ℃ intervals. Different cotton genotypes varied in their in vitro pollen germination and pollen tube length responses to the different temperatures. Maximum pollen germination and pollen tube length ranged from 25.2% to 56.2% and from 414 to 682 μm, respectively.The average cardinal temperatures (Tmin, Topt, and Tmax) also varied among the 14 cultivars and were 11.8,27.3, and 42.7 ℃ for pollen germination and 11.8, 27.8, and 44.1 ℃ for maximum pollen tube length. Variations in boll retention and boll numbers per plant in field experiments were found for the 14 cotton cultivars and the boll retention and boll retained per plant on 20 August varied considerably in different years according to weather conditions. Boll retention on 20 August was highly correlated with maximum pollen germination (R2=0.84) and pollen tube length (R2=0.64). A screening method based on principle component analysis of the combination of pollen characteristics in an in vitro experiment and boll retention testing in the field environment was used in the present study and, as a result, the 14 cotton cultivars could be classified as tolerant, moderately tolerant, moderately susceptible and susceptible to high temperature. 相似文献
27.
The current situation of the animal species biodiversity of macrobenthic fauna in the Jiaozhou Bay (South Shandong Peninsula, Yellow Sea) is reported in the present paper, based on the data from 15 investigation cruises carried out from February 1998 to November 2001. In analyzing the data, the Shannon-Wiener index, and species evenness and richness indices were used to study the trends of variation of the community structure, the species assemblages in the macrobenthic community, the dominant species, and the abundance of macrobenthic fauna in Jiaozhou Bay. A total of 322 species of macrobenthic animals were found in the bay, of which 133 species belong to 44 families of Polychaeta, while 92 species belong to 42 families of Crustacea. The average number of species per sample station ranged from 8 to 26. The Shannon-Wiener indices were very different among the samples, with the highest being recorded from Station 8 in November 2001, and the lowest from Station 9 in August 2001. The number of species, the Shannon-Wiener indices, and the species richness indices from Stations 7 and 9 were generally lower than those from other stations. This is because both the stations are situated at areas with a strong current and where the sediment is coarse sand. Although the richness index of species and the Shannon-Wiener index were high in Station 3, the Pielou evenness index was the lowest of all the sampling stations. This is because the station is located near the culture area of Ruditapes philippinarum, where a high abundance of clams caused low evenness. The results also revealed that the number of species and abundance greatly affected the biodiversity, and some environmental factors such as temperature, salinity, and primary productivity were also closely interrelated with biodiversity. Pollution and overexploitation caused by human activities were very important factors affecting macrobenthic biodiversity. In order to find the best way to enhance and protect living marine resources, the relationship between human activities and the biodiversity of macrobenthos in the Jiaozhou Bay should be studied further. 相似文献
28.
保护性耕作条件下旱地农田麦-豆双序列轮作体系的水分动态及产量效应 总被引:38,自引:2,他引:36
保护性耕作(conservationtillage)能够减少水土流失、提高耕地产量,是一类具有生态保护意义的持续性农业耕作形式。2002年至2004年在定西旱地农业地区进行了保护性耕作条件下旱地农田春小麦豌豆双序列轮作土壤水分动态及产量效应的试验研究,结果表明:保护性耕作能够显著改善0~200cm土层土壤贮水量及含水量,随着降水量的增多土壤对降水的保蓄能力增强。在降水较少年份免耕秸秆覆盖的这种作用表现突出,而在降水充沛的年份免耕地膜覆盖则更具优势。耕层土壤水分因受降水等因素的影响而变化剧烈,耕层以下土壤水分变幅相对较小。播种期、五叶期及收获期土壤具有较高含水量,而开花期土壤含水量则较低。在两种轮作体系中,播种期春小麦和豌豆免耕秸秆覆盖处理0~50cm土层含水量分别较常规耕作增加28%、26%和11%、23%,降水生产效率较常规耕作提高了17.79%~26.81%。在春小麦豌豆轮作体系中免耕秸秆覆盖处理的作物产量(春小麦 豌豆)及水分利用效率分别为3420kghm2和8.11kg(hm2·mm),较常规耕作分别提高26.81%和25.39%。 相似文献
29.
The current situation of the animal species biodiversity of macrobenthic fauna in the Jiaozhou Bay (South Shandong Peninsula, Yellow Sea) is reported in the present paper, based on the data from 15 investigation cruises carried out from February 1998 to November 2001. In analyzing the data, the Shannon-Wiener index, and species evenness and richness indices were used to study the trends of variation of the community structure, the species assemblages in the macrobenthic community, the dominant species, and the abundance of macrobenthic fauna in Jiaozhou Bay. A total of 322 species of macrobenthic animals were found in the bay, of which 133 species belong to 44 families of Polychaeta, while 92 species belong to 42 families of Crustacea. The average number of species per sample station ranged from 8 to 26. The Shannon-Wiener indices were very different among the samples, with the highest being recorded from Station 8 in November 2001, and the lowest from Station 9 in August 2001. The number of species, the Shannon-Wiener indices, and the species richness indices from Stations 7 and 9 were generally lower than those from other stations. This is because both the stations are situated at areas with a strong current and where the sediment is coarse sand. Although the richness index of species and the Shannon-Wiener index were high in Station 3, the Pielou evenness index was the lowest of all the sampling stations. This is because the station is located near the culture area of Ruditapes philippinarum, where a high abundance of clams caused low evenness. The results also revealed that the number of species and abundance greatly affected the biodiversity, and some environmental factors such as temperature, salinity, and primary productivity were also closely interrelated with biodiversity. Pollution and overexploitation caused by human activities were very important factors affecting macrobenthic biodiversity. In order to find the best way to enhance and protect living marine resources, the relationship between human activities and the biodiversity of macrobenthos in the Jiaozhou Bay should be studied further. 相似文献
30.
In this article, RAPD was employed to detect the DNA polymorphism of Carchesium polypinum in three lakes: Nanhu Lake (N), Shahu Lake (S) and Donghu Lake (D). The results were used to deduce the definition of the populations: (1) The 20 primers produced 172 clear bands with an average of 8.6 fragments ranging from 100bp to 1600bp. The other 11 primers produced 59 legible bands with an average of 5.4 fragments ranging from 100bp to 1 500bp; (2) SPSS 12.0 and RAPDistance 1.04 that had similar trees were composed of two parallel main branches. Samples from Shijizhong (Z) of D, Shuiguohu (H) of D and N clustered into a branch and another sample from D — Fengguangcun (F) — gathered with S or made another main branch itself. The result that the three samples from D were separated by the samples from other lakes suggested that the individuals of C. polypinum in D belong to several populations. This discovery will promote micro-hydrobiont population ecology research. In addition, it will help in the study of the essence of the transitional zone and its dispersal and vicariance behavior. We believe that this study will contribute to the study of population differentiation and the mechanism of speciation. 相似文献