检索结果-南通市图书馆

Unveiling an ancient whole-genome duplication event in Stentor,the model unicellular eukaryotes

Science China Life Sciences 2025年

作者： Weibo Zheng Chao Li Zhaorui Zhou Xiao Chen Michael Lynch Ying Yan School of Life Sciences Ludong University Key Laboratory of Evolution & Marine biodiversity (Ministry of Education) and Institute of Evolution & Marine Biodiversity Ocean University of China Biodesign Center for Mechanisms of Evolution Arizona State University Marine College Shandong University

Whole-genome duplication(WGD) events are widespread across eukaryotes and have played a significant role in moulding the genetic architectures of diverse organisms. In the present study, the newly sequenced genome of a giant ciliated protist, Stentor roeselii, provides an opportunity for the analysis of the collinearity and retention of reciprocal best-hit genes between two Stentor species. As a main result, we have unveiled a previously undetected ancient WGD event shaping the genome of its congener, Stentor coeruleus, a model protist used in cytological and evolutionary studies. Genomes of two congeners, S. coeruleus and S. roeselii, are compared and analyzed, revealing that:(i)the former exhibits a much higher retention rate of colinear-gene pairs(28%) than does S. roeselii, and in S. coeruleus, 75% of genes that have a RBH hit in S. roeselii, have paralogs with high amino-acid identity, consistent with a WGD event in the lineage leading to S. coeruleus;(ii) the S. roeselii genome possesses extremely short intergenic regions, implying that the lengths of intergenic regions are under strong selection;(iii) the unique characteristics of introns may have been shaped in the common ancestor of heterotrichs;(iv) gene families that play a role in activities of multiple protein kinases and voltage-gated ion channels expanded rapidly in the ancestor of both taxa, possibly relating to the remarkable regenerative ability in Stentor. This study offers new insights into the evolutionary dynamics of ciliate genomes,with implications for understanding of the processes underlying the evolution of genomic complexity.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Genes and proteins expressed at different life cycle stages in the model protist Euplotes vannus revealed by both transcriptomic and proteomic approaches

引用

Science China Life Sciences 2025年第1期 232-248页

作者： Yaohan Jiang Xiao Chen Chundi Wang Liping Lyu Saleh A.Al-Farraj Naomi A.Stover Feng Gao Key Laboratory of Evolution & Marine biodiversity (Ministry of Education) and Institute of Evolution & Marine biodiversity Ocean University of China Marine College Shandong University Zoology Department College of ScienceKing Saud University Department of Biology Bradley University Laboratory for Marine Biology and Biotechnology Qingdao Marine Science and Technology Center

Sexual reproduction first appeared in unicellular protists and has continued to be an essential biological process in almost all *** protists, which contain both germline and somatic genomes within a single cell, have evolved a special form of sexual reproduction called conjugation that involves mitosis, meiosis, fertilization, nuclear differentiation, genome rearrangement, and the development of unique cellular structures. The molecular basis and mechanisms of conjugation vary dramatically among ciliates, and many details of the process and its regulation are still largely unknown. In order to better comprehend these processes and mechanisms from an evolutionary perspective, this study provides the first comprehensive overview of the transcriptome and proteome profiles during the entire life cycle of the newly-established marine model ciliate Euplotes vannus. Transcriptome analyses from 14 life cycle stages(three vegetative stages and 11 sexual stages) revealed over 26,000 genes that are specifically expressed at different stages, many of which are related to DNA replication,transcription, translation, mitosis, meiosis, nuclear differentiation, and/or genome rearrangement. Quantitative proteomic analyses identified 338 proteins with homologs associated with conjugation and/or somatic nuclear development in other ciliates, including dicer-like proteins, Hsp90 proteins, RNA polymerase Ⅱ and transcription elongation factors, ribosomal-associated proteins, and ubiquitin-related proteins. Four of these homologs belong to the PIWI family, each with different expression patterns identified and confirmed by RT-qPCR,which may function in small RNA-mediated genome rearrangement. Proteins involved in the nonhomologous end-joining pathway are induced early during meiosis and accumulate in the developing new somatic nucleus, where more than 80% of the germline sequences are eliminated from the somatic genome. A number of new candidate genes and proteins likely t

关键词：

来源：

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of patch size, disturbances on diversity and structural traits of tropical semi-evergreen forest in the lowland Indo Burma hotspot: implication on conservation of the threatened tree species

引用

Journal of Mountain Science 2016年第8期13卷 1397-1410页

作者： Koushik MAJUMDAR Badal Kumar DATTA Plant Taxonomy and biodiversity Laboratory Department of Botany Tripura University

Information on geographic distribution, population and threat status of most globally red listed species in the Indo Burma zone are inadequate. Given the increase in the prevalence of isolated forest patches in the part of this hotspot, evaluation is necessary on how size of the remnant forest patches and on-going disturbances affects structure and diversity of remaining habitats including the population of some globally threatened tree species. Quantitative vegetation inventory by 500 m long and lO m wide （0.5 ha） line transects were randomly set in nine fragmented tropical semi-evergreen forest patches in Tripura, Northeast India. The studied forests patches grouped into small, medium and large based on their respected sizes. Spatial variability was analysed in woody species diversity and structure along the patch size gradients and their response to both patch size and anthropogenic disturbances. Out of 167 species, 13 identified as red-listed species by IUCN under the present inventory. Most of the diversity and structural parameters showed statistically significant positive response with the forest patch size, except for stand dominance, disturbance, sapling density and number of aggregated distribution pattern decreased when patch size increased. In addition, most of the diversity and structural attributes showed negative response with disturbances. Present baseline data would serve as an effective tool for management and protection of this important forest type. Future habitat restoration programme and strategies for relocation of additional population and re-introduction of those globally threatened trees are recommended.

关键词： Forest diversity Semi-evergreen forest Threatened species Population composition IndoBurma zone

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Changes of woody species diversity, horizontal and vertical distribution of stems across interior to outside within a primate rich habitat of Northeast India

引用

Journal of Forestry Research 2016年第4期27卷 787-798页

作者： Koushik Majumdar Bal Krishan Choudhary Badal Kumar Datta Plant Taxonomy and biodiversity Lab. Department of Botany Tripura University

The interior forest of protected area（PA）recover quickly in terms of greater diversity and structural complexity than peripheral and outsides, which may be due to high plant-frugivore interactions in the interior forest than the disturbed outsides. To describe the structural and functional differences in tree communities from interior to outside forests with in small PA, we quantitatively analyzed the vegetation of Trishna Wildlife Sanctuary, a rich primate habitat of Northeast India. Vegetation was sampled at C10 cm girth at breast height by 10 m 9 500 m sized20 line transects（10 ha） laid in the interior（N = 7）,peripheral（N = 7） and outside（N = 6） zones of this sanctuary. All transects were ordinated by Principal Component Analysis based on correlation between diversity and existing disturbance indices. We found significant differences（P ／ 0.05） in taxonomic richness and diversity indices between the habitat. Van diagram confirmed greater unique species richness in the interior zone（64） than peripheral（28） and outside（6） zones. Overall density（ha-1） did not differed across the zones, but basal area（m2ha-1） was significantly（P ／ 0.01） high in peripheral zone. Vertical distribution of stem density was linearly declined across zones（r2adj[ 0.70; P ／ 0.01） with increase in the canopy height. Horizontal distribution of adult stems showed significant inverse quadratic relationship（r2adj[ 0.80; P ／ 0.001）, which suggests very low density of canopy forming voluminous trees in the interior *** protection, restoration and management of interior regions are required to preserve local plant genetic diversity and also to maintain suitable habitat for threatened wildlife.

关键词： interior outside habitat restoration Northeast disturbance quickly inverse preserve quadratic

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ethno-medicinal plants used by Bengali communities in Tripura, northeast India

引用

Journal of Forestry Research 2014年第3期25卷 713-716页

作者： Joydeb Majumder Partha P. Bhattacharjee Badal K. Datta Basant K. Agarwala Ecology & biodiversity Laboratories Department of Zoology Tripura University Plant Taxonomy & biodiversity Laboratory Department of Botany Tripura University

Northeastern India has high medicinal plant diversity due to variance in topography and physiognomy. We documented the uses of various medicinal plants by the Bengali people of West district and South district of Tripura state for their own health care as well as for domesti-cated animals. Based on semi structured interviews, group discussions and information from local informants, a total of 93 species of medicinal plants of 52 families and 83 genera were documented. These plants were used to treat more than 55 different human diseases and 6 diseases of livestock. Sixty-eight plant species were used singly and the rest were used in combination with other species for therapeutic formulations of various diseases. Leaves of plants were most often used for most of the ethnobotanical preparations. Maximum consensus value of 96% was recorded for Chromolaena odorata （L.） King ＆amp;H. Rob., and the mini-mum was 15%for Bambusa balcooa Robx. Of the 93 plant species, 75 species showed pharmacological properties. Prospects for augmenting existing knowledge and enhancing the use of traditional medicinal plants are discussed.

关键词： ethnobotanical survey Bengali community traditionalknowledge Tripura state Northeast India

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A new model of speciation

引用

National Science Review 2019年第2期6卷 289-290页

作者： Loren H.Rieseberg Department of botany and biodiversity Research Centre University of British Columbia NSR

In the first paragraph of ‘On the origin of species’, Darwin [1]refers to speciation as that ‘mystery of mysteries’. Although the means by which new species arise is no longer mysterious, some puzzles remain. One such puzzle, which is addressed in a recent paper from Chung-I Wu’s group on mangrove speciation [2],concerns the popular allopatric speciation model. In this model,

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Effect of shifting cultivation and fallow on soil quality index in Mokokchung district,Nagaland,India

引用

Ecological Processes 2022年第1期11卷 561-576页

作者： Wati Temjen Maibam Romeo Singh Tali Ajungla Department of botany Nagaland University798627 LumamiIndia Centre for biodiversity Department of BotanyNagaland University798627 LumamiIndia

Background:Shifting cultivation is a major agriculture practice in the Nagaland state of *** study examines the effect of shifting cultivation and the length of the fallow period on soil quality index(SQI).Four sites were selected for the study,viz.,a shifting cultivation site(SCS),a 3-year-old fallow land(FL-3),a 7-year-old fallow land(FL-7),and a 12-year-old fallow land(FL-12).Soil parameters were recorded seasonally and SQI was calculated from the minimum data ***:With the increase in the fallow period,the values of conductivity,soil organic carbon,available nitrogen,available phosphorus,exchangeable potassium,moisture,clay,and cation exchange capacity of soil ***,soil pH and bulk density decreased with fallow *** additive SQI_(a)values were in the order SCS

关键词： Shifting cultivation Jhum Soil quality index Soil health Seasonal variation Nagaland India

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Park size and prey density limit occurrence of Eurasian Sparrowhawks in urban parks during winter

引用

Avian Research 2018年第3期9卷 206-213页

作者： Claudia Schütz Christian H.Schulze Department of botany and biodiversity Research University of ViennaRennweg 141030 ViennaAustria

Background: Eurasian Sparrowhawks(Accipiter nisus) increasingly represent successful city-dwellers. Thereby, a rich food supply indicated by high numbers of small birds is believed to be the key driver for this bird-eating raptor species to settle in urban environments. However, as small passerine birds show particularly strong antipredator responses, sparrowhawks may not simply focus on patches of highest prey densities, but rather respond strategically to prey behavior, raising the importance of other parameters in determining the occurrence within urban ***: To deepen our knowledge on habitat requirements of urban sparrowhawks, bird surveys were carried out during winter between December 2005 and January 2017 in 36 city parks in Vienna, Austria. Besides food supply also park size, canopy heterogeneity and the connectivity with other green spaces were ***: Occurrence of sparrowhawks was positively affected by increasing park size, prey density and the interaction between both. Bird feeder density and park connectivity with other green spaces were of minor importance in explaining the presence of this species. Canopy heterogeneity didn't affect city park occupancy by Eurasian ***: Our results suggest that large city parks, particularly when characterized by high prey densities, substantially contribute to protect and preserve ecologically important bird species such as raptors within the urban environment—a landscape already struggling with biodiversity losses and functional homogenization.

关键词： Birds of prey Bird feeders Prey abundance Habitat connectivity Tree cover Urban ecology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Benefitting from Geoinformatics: Estimating Floristic Diversity of Warwan Valley in Northwestern Himalaya,India

引用

Journal of Mountain Science 2015年第4期12卷 854-863页

作者： Akhtar Hussain MALIK Irfan RASHID Aijaz Hassan GANIE Anzar Ahmad KHUROO Ghulam Hassan DAR Centre for biodiversity and Taxonomy Department of Botany University of Kashmir Department of Earth Sciences University of Kashmir Department of botany University of Kashmir Mahatma Gandhi Chair on Ecology and Environment Centre for Biodiversity Studies Baba Ghulam Shah Badshah University

The Himalaya harbor rich floristic diversity which is of immense scientific interest and socio-economic *** this study, floristic diversity of a remote alpine valley has been studied based on information extracted from remotely sensed satellite data along with field surveys undertaken during *** of vegetation information from satellite data revealed that ~75% of the area is covered with natural vegetation which comprises lush green coniferous forests, alpine pastures and alpine scrub *** inputs from vegetation information extracted from satellite data, comprehensive field surveys were planned to document the floristic diversity of the *** of species composition showed a total of 285 plant species,belonging to 191 genera in 60 *** these, 250 species are herbs, 14 shrubs, 2 sub-shrubs and 19 *** dicotyledons are represented by 240 species, monocotyledons 30, gymnosperms 04, andpteriodophytes 11 *** is the largest family with 35 *** the present study, 5species（Corydalis cashmeriana, Hippophae rhamnoides, Primula minutissima, Saussurea sacra and Inula orientalis） have been recorded for the first time from this Himalayan *** study demonstrates the benefits of geo-informatics in floristic studies, particularly the robustness of remotely sensed data in identifying areas with potentially high species richness, which would be otherwise difficult in a complex mountainous terrain using traditional floristic surveys *** present study is expected to provide baseline scientific data for cutting edge studies relating to long term ecological research, bioprospecting, possible impacts of changing climate on vegetation and sustainable use of plant resources in this Himalayan region.

关键词： Floristic diversity Northwestern Himalaya Remote sensing GIS Vegetation sampling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evolution of the platycodonoid group with particular references to biogeography and character evolution

引用

Journal of Integrative Plant Biology 2014年第10期56卷 995-1008页

作者： Qiang Wang Xiao-Quan Wang Hang Sun Yan Yu Xing-Jin He De-Yuan Hong State Key Laboratory of Systematic and Evolutionary botany Institute of Botany the Chinese Academy of Sciences Key Laboratory of biodiversity and Biogeography Kunming Institute of Botany the Chinese Academy of Sciences College of Life Sciences Sichuan University

The Qinghai‐Tibet Plateau（QTP）is an important center of origin and diversification for many northern temperate *** hypothesis＂out‐of‐QTP＂suggests that the majority of northern temperate plants have originated and dispersed from the QTP and adjacent *** interesting question is whether the biogeographic history of the platycodonoids（Campanulaceae）,a group mainly distributed in the QTP and adjacent regions,coincides with the hypothesis＂out‐of‐QTP＂？Furthermore,how have the diagnostic characters of the platycodonoids evolved？In the present study,all 10genera of the platycodonoids were sampled for molecular phylogeny and dating analyses,and ancestral states of distribution and characters were *** results do not support the platycodonoids as an＂out‐of‐QTP＂group,but instead they might have descended from Tethyan *** dispersal and diversification of the platycodonoids in Asia might have been driven by the uplift of the *** present study highlights the importance of the Tethyan Tertiary flora for the origin of the Sino‐Himalayan flora and the influence of the uplift of QTP on diversification of northern temperate *** addition,character state reconstruction reveals that the inferior ovary,capsule,long‐colpate pollen,and chromosome number 2n=14 are probably ancestral states.

关键词： Biogeography Campanulaceae character evolution platycodonoids Qinghai‐Tibet Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：