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1.
Ye Yu Xiao-Jing Liu Xiao Ma Zhong-Jie Zhang Tai-Chu Wang Fan Sun Cheng-Xiang Hou Mu-Wang Li 《Insect Science》2020,27(1):2-13
The silkworm Bombyx mori is an important lepidopteran model insect in which many kinds of natural mutants have been identified.However,molecular mechanisms of most of these mutants remain to be explored.Here we report the identification of a gene Bm-app is responsible for the silkworm minute wing(mw)mutation which exhibits exceedingly small wings during pupal and adult stages.Compared with the wild type silkworm,relative messenger RNA expression of Bm-app is significantly decreased in the ul 1 mutant strain which shows mw phenotype.A 10 bp insertion in the putative promoter region of the Bm-app gene in mw mutant strain was identified and the dual luciferase assay revealed that this insertion decreased Bm-app promoter activity.Furthermore,clustered regularly interspaced short palindromic repeats/RNA-guided Cas9 nucleases-mediated depletion of the Bm-app induced similar wing defects which appeared in the mw mutant,demonstrating that Bm-app controls wing development in B.mori.Bm-app encodes a palmitoyltransferase and is responsible for the palmitoylation of selected cytoplasmic proteins,indicating that it is required for cell mitosis and growth during wing development.We also discuss the possibility that Bm-app regulates wing development through the Hippo signaling pathway in B.mori. 相似文献
2.
Lei Wang Xiao-Wei Zhang Lin-Lin Pan Wan-Fei Liu Da-Peng Wang Guang-Yu Zhang Yu-Xin Yin An Yin Shan-Gang Jia Xiao-Guang Yu Gao-Yuan Sun Song-Nian Hu Ibrahim S. AI-Mssallem Jun Yu 《Entomologia Sinica》2013,(6):689-702
The red palm weevil (RPW; Rhynchophorusferrugineus) is a devastating pest of palms, prevalent in the Middle East as well as many other regions of the world. Here, we report a large-scale de novo complementary DNA (cDNA) sequencing effort that acquired ~5 million reads and assembled them into 26 765 contigs from 12 libraries made from samples of different RPW developmental stages based on the Roche/454 GS FLX platform. We annotated these contigs based on the publically available known insect genes and the Tribolium castaneum genome assembly. We find that over 80% of coding sequences (CDS) from the RPW contigs have high-identity homologs to known proteins with complete CDS. Gene expression analysis shows that the pupa and larval stages have the highest and lowest expression levels, respectively. In addition, we also identified more than 60 000 single nucleotide polymorphisms and 1 200 simple sequence repeat markers. This study provides the first large-scale eDNA dataset for RPW, a much-needed resource for future molecular studies. 相似文献
3.
4.
PJ Cai X Xiao YR He WW Li GL Zang GP Sheng M Hon-Wah Lam L Yu HQ Yu 《Biosensors & bioelectronics》2013,39(1):306-310
The enhanced electricity generation in a biocathode bio-electrochemical system (BES) with Microcystis aeruginosa IPP as the cathodic microorganism under illumination is investigated. The results show that this cyanobacterium is able to act as a potential cathodic microorganism under illumination. In addition, M. aeruginosa IPP is found to produce reactive oxygen species (ROS) in its growth in the BES. ROS, as more competitive electron acceptors than oxygen, are utilized prior to oxygen. The BES current is substantially reduced when the ROS production is inhibited by mannitol, indicating that the ROS secreted by the cyanobacterium play an important role in the electricity generation of such a biocathode BES. This work demonstrates that the ROS released by cyanobacteria benefit for an enhanced electricity generation of BES. 相似文献
5.
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
6.
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
7.
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
8.
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
9.
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
10.
Liangliang Yu Leqi Huang Shuang Zeng Guirong Tang Sunjun Wang Ningning Li Junhui Yan Li Luo 《Acta biochimica et biophysica Sinica》2019,(4):448-451
ROS include superoxide anion radical (O2^-), hydrogen peroxide (H2O2), singlet oxygen (0-0), hydroxyl radical (OH ), and hydroxyl anion (OH-). O2^-, the radical with the highest oxidation compacity to produce H2O2, OH and OH^-, is a byproduct of aerobic respiration in organisms. Rhizobia and their legume hosts are aerobic organisms, and nitrogen-fixing nodules formed on legume roots are developed from their symbiotic in teractions. Therefore, ROS are generated in legume nodules through aerobic respiration by both symbiotic partners. 相似文献