Endangered Species

濒危物种
  • 文章类型: Journal Article
    西藏东南部的墨脱是各种各样的野生动物的家园。然而,研究这些哺乳动物的物种目录,分布,保护状况仍然不足,尽管它们在维持生态平衡方面发挥了关键作用。这项研究进行了一项相机诱捕调查,以评估哺乳动物的生物多样性以及在格当的自然栖息地中保护哺乳动物的重要性,墨狗还讨论了藏东南山区野生动物保护研究的未来方向和应用前景。调查,从2023年4月到2024年5月,有19,754个相机陷阱天,揭示了5个目14科的25种哺乳动物。其中,四个被列为濒危物种,五个是脆弱的,两个被IUCN红色名录威胁到了,有9人在中国脊椎动物红色名录上被列为极度濒危或濒危,七种是中国国家一级重点保护野生动物。食肉目表现出最高的多样性,包括12种。此外,这项研究填补了有关IUCN中贡山muntjacMuntiacusgongshanensis代表性不足的知识空白,并首次为雅鲁藏布江沿岸的喜马拉雅红熊猫Ailurusfulgens和中国红熊猫Ailurusstyani的共存记录提供了新的见解,并记录了四个大中型物种的新海拔上限。关于相机陷阱捕获的相对丰度指数(RAI),确定的最普遍的物种是白颊猕猴,其次是贡山蒙太奇和喜马拉雅山塞罗·卡比尼斯塔尔。监测还捕获了一些家犬和牲畜,以及人类的干扰。这些发现强调了保护这些哺乳动物的重要性,并强调了保护其栖息地和减少威胁其生存的人类活动的必要性。从而维持该地区的生态平衡。此外,这项研究强调了Gedang\对全球哺乳动物多样性保护工作的重要性,为有效的野生动物保护策略提供必要的数据。
    The Medog in southeastern Tibet is home to a diverse range of wild animals. However, research on these mammals\' species directories, distribution, and conservation status remains insufficient, despite their crucial role in maintaining ecological balance. The study carried out a camera-trapping survey to assess mammal biodiversity and the significance of mammal protection in their natural habitats in Gedang, Medog. Future directions and application prospects of the study for wildlife conservation in the southeastern Tibetan mountains were also discussed. The survey, spanning from April 2023 to May 2024, with 19,754 camera trap days, revealed 25 mammalian species across five orders and 14 families. Among these, four classified as Endangered, five as Vulnerable, two as Near Threatened on the IUCN Red List, nine were categorized as Critically Endangered or Endangered on the Red List of China\'s Vertebrates, and seven were China\'s national first-class key protected wildlife. The order Carnivora exhibited the highest diversity, comprising 12 species. Furthermore, the study filled the knowledge gap regarding the underrepresentation of Gongshan muntjac Muntiacus gongshanensis in IUCN and provided new insights into the recorded coexistence of the Himalayan red panda Ailurus fulgens and Chinese red panda Ailurus styani along the Yarlung Zangbo River for the first time, and also documented new upper elevation limits for four large to medium-sized species. Regarding the relative abundance indices (RAI) captured by camera traps, the most prevalent species identified was the White-cheeked macaque Macaca leucogenys, followed by the Gongshan muntjac and Himalayan serow Capricornis thar. The monitoring also captured a number of domestic dogs and livestock, as well as human disturbances. These findings underscore the importance of conserving these mammals and emphasize the need for conservation efforts to protect their habitats and reduce human activities that threaten their survival, thereby maintaining the ecological balance of the region. Additionally, the research highlighted Gedang\'s significance to global conservation efforts for mammalian diversity, providing essential data for effective wildlife conservation strategies.
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  • 文章类型: Journal Article
    背景:贝母是一种濒危药用植物,以其显着的治疗特性而闻名。不幸的是,由于森林栖息地的破坏,其人口急剧下降。因此,有效地保护乌苏里氏菌免于灭绝是一个重大挑战。对其遗传基础的深刻理解至关重要。迄今为止,关于乌苏里的完整线粒体基因组的研究尚未见报道。
    结果:通过整合PacBio和Illumina测序技术,对乌苏里氏菌的完整线粒体基因组进行了测序和组装,显示13条环状染色体,总计737,569bp,平均GC含量为45.41%。共有55个基因被注释在这个有丝分裂基因组中,包括2个rRNA基因,12个tRNA基因,和41个PCGs。乌苏里氏菌的线粒体基因组包含192个SSR和4,027个分散重复序列。在ussuriensis的PCGs中,超过1的RSCU值的90.00%表现出对A末端或U末端密码子的偏好。此外,在这些PCG中预测了505个RNA编辑位点。选择性压力分析表明,对大多数PCGs进行负选择以保持线粒体功能,作为基因nad3的显着例外,显示阳性选择。乌苏里氏菌线粒体和叶绿体基因组之间的比较揭示了20个同源片段,总计8,954bp。核苷酸多样性分析揭示了基因之间的变异,基因atp9最为显著。尽管保留了GC含量,有丝分裂体大小在六个密切相关的物种中差异显著,共线性分析证实了它们的基因组结构缺乏保守性。系统发育分析表明,乌苏里百合与百合有密切关系。
    结论:在这项研究中,我们测序并注释了乌苏里氏菌的有丝分裂基因组,并将其与其他密切相关物种的有丝分裂基因组进行了比较。除了基因组特征和进化位置,本研究也为进一步了解和利用该药用植物提供了宝贵的基因组资源。
    BACKGROUND: Fritillaria ussuriensis is an endangered medicinal plant known for its notable therapeutic properties. Unfortunately, its population has drastically declined due to the destruction of forest habitats. Thus, effectively protecting F. ussuriensis from extinction poses a significant challenge. A profound understanding of its genetic foundation is crucial. To date, research on the complete mitochondrial genome of F. ussuriensis has not yet been reported.
    RESULTS: The complete mitochondrial genome of F. ussuriensis was sequenced and assembled by integrating PacBio and Illumina sequencing technologies, revealing 13 circular chromosomes totaling 737,569 bp with an average GC content of 45.41%. A total of 55 genes were annotated in this mitogenome, including 2 rRNA genes, 12 tRNA genes, and 41 PCGs. The mitochondrial genome of F. ussuriensis contained 192 SSRs and 4,027 dispersed repeats. In the PCGs of F. ussuriensis mitogenome, 90.00% of the RSCU values exceeding 1 exhibited a preference for A-ended or U-ended codons. In addition, 505 RNA editing sites were predicted across these PCGs. Selective pressure analysis suggested negative selection on most PCGs to preserve mitochondrial functionality, as the notable exception of the gene nad3 showed positive selection. Comparison between the mitochondrial and chloroplast genomes of F. ussuriensis revealed 20 homologous fragments totaling 8,954 bp. Nucleotide diversity analysis revealed the variation among genes, and gene atp9 was the most notable. Despite the conservation of GC content, mitogenome sizes varied significantly among six closely related species, and colinear analysis confirmed the lack of conservation in their genomic structures. Phylogenetic analysis indicated a close relationship between F. ussuriensis and Lilium tsingtauense.
    CONCLUSIONS: In this study, we sequenced and annotated the mitogenome of F. ussuriensis and compared it with the mitogenomes of other closely related species. In addition to genomic features and evolutionary position, this study also provides valuable genomic resources to further understand and utilize this medicinal plant.
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  • 文章类型: Journal Article
    铁皮石斛是一种珍贵的中药,具有很高的药用和观赏价值。然而,其线粒体基因组的鉴定仍在等待中.这里,我们组装了D.loddigesii完整的线粒体基因组,并发现其基因组具有复杂的多染色体结构。洛迪吉的有丝分裂基因组由17个环状亚基因组组成,大小从16,323bp到56,781bp不等。有丝分裂体的总长度为513,356bp,GC含量为43.41%。有丝分裂基因组包含70个基因,包含36个蛋白质编码基因(PCGs),31个tRNA基因,和3个rRNA基因。此外,我们在所有PCGs中检测到403个重复序列,并鉴定出482个RNA编辑位点和8154个密码子.在序列相似性分析之后,发现了27个与有丝分裂基因组和叶绿体基因组均具有同源性的片段,占洛迪奇有丝分裂基因组的9.86%。基因合成分析揭示了洛迪吉氏杆菌和相关物种的有丝分裂基因组中的许多序列重排。系统发育分析强烈支持D.loddigesii和D.Amplum形成了具有100%引导支持的单个进化枝。结果将显著增加兰花线粒体基因组数据库,为铁皮石斛复杂的线粒体基因组结构提供了深刻的见解。
    Dendrobium loddigesii is a precious traditional Chinese medicine with high medicinal and ornamental value. However, the characterization of its mitochondrial genome is still pending. Here, we assembled the complete mitochondrial genome of D. loddigesii and discovered that its genome possessed a complex multi-chromosome structure. The mitogenome of D. loddigesii consisted of 17 circular subgenomes, ranging in size from 16,323 bp to 56,781 bp. The total length of the mitogenome was 513,356 bp, with a GC content of 43.41%. The mitogenome contained 70 genes, comprising 36 protein-coding genes (PCGs), 31 tRNA genes, and 3 rRNA genes. Furthermore, we detected 403 repeat sequences as well as identified 482 RNA-editing sites and 8154 codons across all PCGs. Following the sequence similarity analysis, 27 fragments exhibiting homology to both the mitogenome and chloroplast genome were discovered, accounting for 9.86% mitogenome of D. loddigesii. Synteny analysis revealed numerous sequence rearrangements in D. loddigesii and the mitogenomes of related species. Phylogenetic analysis strongly supported that D. loddigesii and D. Amplum formed a single clade with 100% bootstrap support. The outcomes will significantly augment the orchid mitochondrial genome database, offering profound insights into Dendrobium\'s intricate mitochondrial genome architecture.
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  • 文章类型: Journal Article
    最近对雌性双翅目昆虫(Brachycera)的研究正在为这种非常多样化的全代谢昆虫进化历史提供全面而细致的了解。Oestroidea,其中包括强大的害虫,如各种苍蝇,botfly,肉蝇感染牲畜,宠物和人类,主要由有益物种组成,它们在各种害虫上充当清道夫或寄生虫。在我们的研究中,我们使用基因组方法来阐明NesodexiacorsicanaVilleneuve的系统发育位置,1911年(双翅目:Calliphoridae),科西嘉岛特有的一种神秘的类人猿物种,其特征是独特的形态特征,多年来一直困扰着分类学家。与最初的假设相反,我们的结果是NesodexiaVilleneuve,1911年在Calliphoridae亚科中,陆地等足类寄生虫的一小部分谱系。通过对成年男女和卵的详细形态分析,我们发现了与我们的系统基因组重建一致的重要见解。该物种独特的形态特征,再加上其受限制和支离破碎的栖息地,强调其潜在的保护重要性。我们划定了N.corsicana的占用区域,并使用特定的IUCN红色名录标准评估了其“受威胁”类别。此外,我们绘制了其范围内的可用栖息地,并确定了由N.corsicana触发的潜在关键生物多样性区域(KBA)。科西嘉地区公园仅部分覆盖了新的潜在KBA。最后,我们绘制了岛上栖息地的分布图,以评估该物种超出其当前已知地理范围的潜在分布。
    Recent studies on oestroidean Diptera (Brachycera) are providing a comprehensive and nuanced understanding of the evolutionary history of this remarkably diverse clade of holometabolous insects. The Oestroidea, which includes formidable pests such as various blowflies, botflies, and flesh flies that infest livestock, pets and humans, are mostly composed of beneficial species that act as scavengers or parasitoids on various pest insects. In our research, we used genomic methods to elucidate the phylogenetic position of Nesodexia corsicana Villeneuve, 1911 (Diptera: Calliphoridae), a mysterious oestroid species endemic to Corsica and characterized by distinctive morphological features that have puzzled taxonomists for years. Contrary to initial hypotheses, our results place Nesodexia Villeneuve, 1911 within the Calliphoridae subfamily Rhinophorinae, a small lineage of terrestrial isopod parasitoids. Through detailed morphological analysis of adults of both sexes and eggs, we uncovered significant insights consistent with our phylogenomic reconstruction. The unique morphological features of the species, coupled with its restricted and fragmented habitat, highlight its potential conservation importance. We delineated the area of occupancy for N. corsicana and assessed its \"threatened\" category using specific IUCN Red List criteria. In addition, we mapped the available habitat within its range and determined potential key biodiversity areas (KBA) triggered by N. corsicana. New potential KBAs are only partially covered by the Corsican Regional Park. Finally, we mapped the distribution of habitats on the island to assess the potential distribution of the species beyond its currently known geographic range.
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  • 文章类型: Dataset
    云南沉香是一种濒临灭绝的沉香树,目前已被列入IUCN濒危物种红色名录。其生产的沉香具有重要的药用和经济价值,但是由于人类的破坏和栖息地的减少,其人口急剧下降。因此,获得云南A的基因组信息有利于其保护工作。我们使用BGI短读数组装了云南A的染色体水平参考基因组,PacBioHiFi长读到,再加上Hi-C技术。云南A.的最终基因组组装为847.04Mb,N50大小为99.68Mb,其中805.49Mb的碱基锚定在八个假染色体上。在组装中检测到两个无间隙假染色体。总共注释了27,955个蛋白质编码基因以及74.65%的重复元件。这些发现可能为保护提供宝贵的资源,功能基因组学,和云南A的分子育种,以及沉香的分子系统发育和进化模式。
    Aquilaria yunnanensis is an endangered agarwood-producing tree currently listed on the IUCN Red List of Threatened Species. The agarwood it produces has important medicinal and economic value, but its population has sharply declined due to human destruction and habitat reduction. Therefore, obtaining genomic information on A. yunnanensis is beneficial for its protection work. We assembled a chromosome-level reference genome of A. yunnanensis by using BGI short reads, PacBio HiFi long reads, coupled with Hi-C technology. The final genome assembly of A. yunnanensis is 847.04 Mb, with N50 size of 99.68 Mb, in which 805.49 Mb of the bases were anchored on eight pseudo-chromosomes. Two gapless pseudo-chromosomes were detected in the assembly. A total of 27,955 protein-coding genes as well as 74.65% repetitive elements were annotated. These findings may provide valuable resources in conservation, functional genomics, and molecular breeding of A. yunnanensis, as well as the molecular phylogenetics and evolutionary patterns in Aquilaria.
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  • 文章类型: Dataset
    Kmeriaseptentrionalis是广西特有的濒危树种,中国,并被列入国际自然保护联盟的红色名录。缺乏遗传信息和高质量的基因组数据阻碍了对该物种的保护工作和研究。在这项研究中,我们提出了K.septentrionalis的染色体水平基因组组装。基因组最初组装为2.57Gb,重叠群N50为11.93Mb。Hi-C指导的基因组组装使我们能够将初始重叠群总长度的98.83%锚定到19个假染色体上,导致支架N50为135.08Mb。最终的染色体水平基因组,跨越2.54Gb,BUSCO的完整性达到98.9%,包含1.67Gb重复元件和35,927个编码基因。这种高质量的基因组组装为了解这种濒危树种的保护相关性状和生物学特性的遗传基础提供了宝贵的资源。此外,它为木兰科的进化研究奠定了重要的基础。
    Kmeria septentrionalis is a critically endangered tree endemic to Guangxi, China, and is listed on the International Union for Conservation of Nature\'s Red List. The lack of genetic information and high-quality genome data has hindered conservation efforts and studies on this species. In this study, we present a chromosome-level genome assembly of K. septentrionalis. The genome was initially assembled to be 2.57 Gb, with a contig N50 of 11.93 Mb. Hi-C guided genome assembly allowed us to anchor 98.83% of the total length of the initial contigs onto 19 pseudochromosomes, resulting in a scaffold N50 of 135.08 Mb. The final chromosome-level genome, spaning 2.54 Gb, achieved a BUSCO completeness of 98.9% and contained 1.67 Gb repetitive elements and 35,927 coding genes. This high-quality genome assembly provides a valuable resource for understanding the genetic basis of conservation-related traits and biological properties of this endangered tree species. Furthermore, it lays a critical foundation for evolutionary studies within the Magnoliaceae family.
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  • 文章类型: Journal Article
    对来自“脆弱的”中国特有针叶树Tsugaforrestii(福雷斯特铁杉)的树枝和针叶的90%MeOH提取物的EtOAc可溶部分进行了广泛的植物化学研究,导致了50种结构多样的二萜化合物的分离和表征,包括15个未报告的C-18羧化的(tsugaforresticidsA-O,1-15,分别。).其中,化合物1-7是松香-18-酸,化合物8是一种abieten-18-琥珀酸盐,化合物10-12是podocarpen-18-oic酸,而化合物13-15是匹马环型,异imarane型,和totarane型二萜酸,分别。它们的结构和绝对构型是通过光谱方法的组合确定的,GIAONMR计算和DP4+概率分析,电子圆二色性(ECD)数据,和单晶X射线衍射分析。评估所有分离株对ATP-柠檬酸裂解酶(ACL)的抑制活性,细胞代谢的关键酶.发现TsugaforrestiacidsE(5)和H(8)对ACL有显著的抑制作用,IC50值为5.3和6.2μM,分别。通过分子对接研究检查生物活性分子与ACL酶的相互作用。分离的二萜化合物还提供了化学分类学证据,以支持Tsuga与其最亲密的姐妹组(Nothotsuga)的划界。上述发现强调了保护具有独特和多样化次生代谢产物的植物物种的重要性。这可能是治疗ACL相关疾病的新治疗剂的潜在来源。
    An extensive phytochemical investigation on the EtOAc-soluble fraction of the 90% MeOH extract from the twigs and needles of the \'vulnerable\' Chinese endemic conifer Tsuga forrestii (Forrest\'s hemlock) led to the isolation and characterization of 50 structurally diverse diterpenoids, including 15 unreported C-18 carboxylated ones (tsugaforrestiacids A-O, 1-15, resp.). Among them, compounds 1-7 are abieten-18-oic acids, compound 8 is an abieten-18-succinate, and compounds 10-12 are podocarpen-18-oic acids, whereas compounds 13-15 are pimarane-type, isopimarane-type, and totarane-type diterpenoid acids, respectively. Their structures and absolute configurations were determined by a combination of spectroscopic methods, GIAO NMR calculations and DP4+ probability analyses, electronic circular dichroism (ECD) data, and single crystal X-ray diffraction analyses. All the isolates were evaluated for their inhibitory activities against the ATP-citrate lyase (ACL), a key enzyme in cellular metabolism. Tsugaforrestiacids E (5) and H (8) were found to have significant inhibitory effects against ACL, with IC50 values of 5.3 and 6.2 μM, respectively. The interactions of the bioactive molecules with the ACL enzyme were examined by molecular docking studies. The isolated diterpenoids also provide chemotaxonomic evidence to support the delimitation of Tsuga from its closest sister group (Nothotsuga). The above findings highlight the importance of protecting plant species with unique and diverse secondary metabolites, which may be potential sources of new therapeutic agents for the treating ACL-associated diseases.
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  • 文章类型: Journal Article
    许多濒危物种生活在分散和孤立的种群中,遗传变异性低,近亲繁殖的迹象,和小的有效种群规模-所有特征都提高了它们的灭绝风险。平头泥ach(Oreonectesplatyhealus),一条小鱼,遍布中国南方,但只在山坡的源头;结果,它们在空间上与特定种群隔离。我们调查了香港16个白头鱼种群的单核苷酸多态性,以确定来自不同溪流的泥炭种群是否在基因上相互分离,表现出低水平的遗传多样性,近亲繁殖的迹象,当代有效人口规模较小。平均观测杂合度的估计(HO=0.0473),平均加权核苷酸多样性(πw=0.0546)和当代有效种群规模(Ne=10.2~129.8)非常低,根据亲缘关系估计,几个种群显示出明显的近亲繁殖迹象。群体间的遗传分化程度很高(平均FST=0.668),即使在很短的地理距离(<1.5公里),有清晰的距离隔离模式。这些结果表明,香港O.platycalus种群经历了强烈的遗传漂移和遗传变异性丧失,因为最后一次冰川期后海平面上升降低了古排水沟之间的连通性,隔离源头人口。所有这一切,此外,白头翁种群的遗传多样性水平和当代有效种群规模低于大多数其他淡水鱼,表明它们面临很高的局部灭绝风险,并且未来的适应能力有限。
    Many endangered species live in fragmented and isolated populations with low genetic variability, signs of inbreeding, and small effective population sizes - all features elevating their extinction risk. The flat-headed loach (Oreonectes platycephalus), a small noemacheilid fish, is widely across southern China, but only in the headwaters of hillstreams; as a result, they are spatially isolated from conspecific populations. We surveyed single nucleotide polymorphisms in 16 Hong Kong populations of O. platycephalus to determine whether loach populations from different streams were genetically isolated from each other, showed low levels of genetic diversity, signs of inbreeding, and had small contemporary effective population sizes. Estimates of average observed heterozygosity (HO = 0.0473), average weighted nucleotide diversity (πw = 0.0546) and contemporary effective population sizes (Ne = 10.2 ~ 129.8) were very low, and several populations showed clear signs of inbreeding as judged from relatedness estimates. The degree of genetic differentiation among populations was very high (average FST = 0.668), even over short geographic distances (<1.5 km), with clear patterns of isolation by distance. These results suggest that Hong Kong populations of O. platycephalus have experienced strong genetic drift and loss of genetic variability because sea-level rise after the last glaciation reduced connectedness among paleodrainages, isolating populations in headwaters. All this, together with the fact that the levels of genetic diversity and contemporary effective population sizes within O. platycephalus populations are lower than most other freshwater fishes, suggests that they face high local extinction risk and have limited capacity for future adaptation.
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  • 文章类型: Journal Article
    四种未描述的聚酮化合物,beshanzoneA(1)和B(2)以及beshanhexanolsA(3)和B(4),从与极度濒危的中国特有针叶树冷杉相关的两种内生真菌的水稻发酵中分离出三种已知的(5-7)。γ-丁内酯衍生物1、2和5分离自Phomopsissp。BSZ-AZ-2,一种有趣的菌株,这次引起了我们的注意。在对青霉菌BSZ-P-4-1的后续研究中获得了环己醇衍生物3、4、6和7。化合物1-4的化学结构包括绝对构型通过光谱法测定,Mo2(OAc)4诱导电子圆二色性(IECD),GIAONMR计算和DP4+概率分析。特别是,化合物2包含一个新的5/5双环系统,其可以通过水解随后进行Aldol反应从已知化合物5生物源衍生。评估所有分离株对一小组细菌和真菌病原体的抗微生物活性。化合物6和7对白色念珠菌表现出中等抑制活性,MIC值为16和32μg/mL,分别。
    Four undescribed polyketides, beshanzones A (1) and B (2) as well as beshanhexanols A (3) and B (4), along with three known ones (5-7) were isolated from the rice fermentation of two endophytic fungi associated with the critically endangered Chinese endemic conifer Abies beshanzuensis. γ-Butyrolactone derivatives 1, 2, and 5 were isolated from Phomopsis sp. BSZ-AZ-2, an interesting strain that drawn our attention this time. The cyclohexanol derivatives 3, 4, 6, and 7 were obtained during a follow-up investigation on Penicillium commune BSZ-P-4-1. The chemical structures including absolute configurations of compounds 1-4 were determined by spectroscopic methods, Mo2(OAc)4 induced electronic circular dichroism (IECD), GIAO NMR calculations and DP4+ probability analyses. In particular, compound 2 contains a novel 5/5 bicyclic ring system, which might be biogenetically derived from the known compound 5 through hydrolysis followed by an Aldol reaction. All isolates were evaluated for their antimicrobial activities against a small panel of bacterial and fungal pathogens. Compounds 6 and 7 showed moderate inhibitory activities against Candida albicans, with MIC values of 16 and 32 μg/mL, respectively.
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  • 文章类型: Journal Article
    广玉兰是我国极为濒危的特有树种。为了阐明洛龙根的遗传基础,我们使用整合植物树皮的样本进行了全面的转录组分析,叶子,和鲜花。从头转录组组装产生177,046个转录物和42,518个编码序列。值得注意的是,我们鉴定了796个物种特异性基因,富含细胞器基因调控和防御反应。密码子使用偏倚分析显示,突变偏倚似乎是塑造物种遗传结构的选择的主要驱动因素。基于同源和直系同源基因对的dN/dS值的进化分析表明,纯化选择占主导地位,表明对大多数基因的强烈进化约束。与木兰的比较转录组学分析鉴定了大约1000个超保守基因,富含必需的细胞过程,如转录调控,蛋白质合成,和基因组稳定性。有趣的是,与sinica和厚朴相比,仅检测到有限数量的511个快速进化的基因。这些基因富集在与适应特定环境相关的代谢过程中,潜在地限制了物种扩大其范围的能力。我们的发现有助于理解M.lotungensis的遗传结构,并表明适应性基因数量不足导致其濒危状态。
    Magnolia lotungensis is an extremely endangered endemic tree in China. To elucidate the genetic basis of M. lotungensis, we performed a comprehensive transcriptome analysis using a sample integrating the plant\'s bark, leaves, and flowers. De novo transcriptome assembly yielded 177,046 transcripts and 42,518 coding sequences. Notably, we identified 796 species-specific genes enriched in organelle gene regulation and defense responses. A codon usage bias analysis revealed that mutation bias appears to be the primary driver of selection in shaping the species\' genetic architecture. An evolutionary analysis based on dN/dS values of paralogous and orthologous gene pairs indicated a predominance of purifying selection, suggesting strong evolutionary constraints on most genes. A comparative transcriptomic analysis with Magnolia sinica identified approximately 1000 ultra-conserved genes, enriched in essential cellular processes such as transcriptional regulation, protein synthesis, and genome stability. Interestingly, only a limited number of 511 rapidly evolving genes under positive selection were detected compared to M. sinica and Magnolia kuangsiensis. These genes were enriched in metabolic processes associated with adaptation to specific environments, potentially limiting the species\' ability to expand its range. Our findings contribute to understanding the genetic architecture of M. lotungensis and suggest that an insufficient number of adaptive genes contribute to its endangered status.
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