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11.
云南省作为中国生物多样性最高的省份, 其详实的物种本底资料对我国生物多样性研究和保护具有重要意义。本文在前期研究的基础上, 结合实体标本, 汇总编制了云南省现生、原生爬行动物更新名录。截至2021年12月31日, 云南省记录爬行动物25科82属235种, 其中龟鳖目4科12属16种, 有鳞目蜥蜴亚目6科20属72种, 蛇亚目15科50属147种。较《云南两栖爬行动物》确认新增82种, 存疑收录21种, 移除23种。基于先前云南省爬行动物区划和更新后的物种分布信息, 将云南省爬行动物地理分为6个动物地理区, 即滇西北横断山区、滇西山地区、滇南山地区、滇东南山地区、滇中高原区以及滇东北山地区; 其中滇西北横断山区、滇西山地区、滇中高原区和滇东南山地区的范围与先前研究相比有所调整。结合调整后的爬行动物地理区划, 对物种分布、物种特有性、受威胁状况等给出了统计结果。云南省爬行动物特有物种、国内仅见于云南的非特有物种数量较多, 受威胁等级高。建议今后继续加大分类学研究投入, 对滇西北、滇中特有爬行动物分布集中的区域积极开展栖息地保护工作, 同时在最新调整的《国家重点保护野生动物名录》基础上, 定期组织专家研讨, 对《云南省省级重点保护动物名录》提出更新建议。 相似文献
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The morphology, morphogenesis and molecular phylogeny of Parabistichella dieckmanni (Foissner, 1998) Foissner, 2016, isolated from north China, were investigated. The Chinese population was characterized as having five to seven frontal cirri in corona, four to seven buccal cirri arranged in a row, two to four short frontal rows and two long frontoventral rows, three to seven transverse cirri, four macronuclear nodules, three dorsal kineties following a Gonostomum-pattern, and caudal cirri absent. Morphogenetic research reveals that the main characteristics during binary fission are as follows: (1) the long left frontoventral row is formed by two or three anlagen; (2) the posterior part of the parental adoral zone of membranelles is renewed, and the oral primordium of the opisthe is formed intrakinetally; (3) FVT-anlagen I to VI (or V, VII) produce each a frontal cirrus to form the frontal corona; (4) development of dorsal kineties follows the Gonostomum-pattern. Phylogenetic analyses showed that P. dieckmanni does not group with other Parabistichella species. Therefore, the genus Parabistichella is polyphyletic. Additionally, Parabistichella variabilis n. comb. (basionym: Bistichella variabilis He & Xu, 2011) and Parabistichella cheni n. nom. (basionym: Parabistichella variabilis Jiang et al., 2013) were suggested. 相似文献
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Algae are ubiquitous in the marine environment, and the ways in which they interact with bacteria are of particular interest in the field of marine ecology. The interactions between primary producers and bacteria impact the physiology of both partners, alter the chemistry of their environment, and shape microbial diversity. Although algal-bacterial interactions are well known and studied, information regarding the chemical-ecological role of this relationship remains limited, particularly with respect to quorum sensing (QS), which is a system of stimuli and response correlated to population density. In the microbial biosphere, QS is pivotal in driving community structure and regulating behavioral ecology, including biofilm formation, virulence, antibiotic resistance, swarming motility, and secondary metabolite production. Many marine habitats, such as the phycosphere, harbor diverse populations of microorganisms and various signal languages (such as QS-based autoinducers). QS-mediated interactions widely influence algal-bacterial symbiotic relationships, which in turn determine community organization, population structure, and ecosystem functioning. Understanding infochemicals-mediated ecological processes may shed light on the symbiotic interactions between algae host and associated microbes. In this review, we summarize current achievements about how QS modulates microbial behavior, affects symbiotic relationships, and regulates phytoplankton chemical-ecological processes. Additionally, we present an overview of QS-modulated co-evolutionary relationships between algae and bacterioplankton, and consider the potential applications and future perspectives of QS. 相似文献
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Tao Zhong Jianmei Zhang Xiaoying Han Xiaoxiao Gongye Tianqi Lyu Menghan Jiang Kaiwei Yu Xiaoqian Meng Dong Cheng Hui Lyu Tianliang Zhang Lei Zhang Shuzhen Liu 《Journal of cellular biochemistry》2019,120(9):15337-15346
3,3′,4,4′,5-Polychlorinated biphenyl (PCB126) is a persistent organic environmental pollutant which can affect various biological activities of organisms, such as immunity, neurological function, and reproduction. In our study, we aimed to investigate the effects of PCB126 on granulosa cells (GCs). GCs were collected from ovaries in PMSG-treated mice, after 24 hours culture. GCs were then incubated with 10 pg/mL, 100 pg/mL, and 10 ng/mL of PCB126 for another 24 hours. Following these steps, exposed GCs were collected for further experimentation. Our data showed that the number of GCs in the 10 ng/mL PCB126 decreased. Meanwhile, pyknotic nuclei and condensed chromatin increased, while the apoptotic cells in the 10 ng/mL PCB126 group were significantly increased. Furthermore, the expression of the apoptotic executive protein caspase-3 increased after PCB126 treatment. The expression of Bax, Bcl-2, and Bim related to the mitochondrial apoptosis pathway were also influenced to different degrees. Thus, our data suggested that PCB126 affect the GCs apoptosis, and mitochondrial apoptosis pathway was involved in this process. 相似文献
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Cd2+ provokes inositol trisphosphateproduction and releases stored Ca2+, apparently by binding to a zinc site in the external domain of an orphan receptor. One pM Cd2+ evokes an immediate spike in cytosolic free Ca2+, which is similar to that evoked by bradykinin. Platelet-derived growth factor (PDGF) also increases free Ca2+ in human dermalfibroblasts, but there is a distinct lag before free Ca2+ rises in response to PDGF. Genistein, which selectively inhibits tyrosine kinases, markedly inhibited Ca2+ mobilization evoked by PDGF. Calcium mobilization triggered by cadmium or bradykinin was relatively insensitive to genistein. The PDGF receptor is known to be a tyrosine kinase, whichphosphorylates and thereby activatesphospholipase C, whereas a G protein couples the bradykinin receptor to anotherphospholipase C isoform. These findings support the hypothesis that the orphan receptor triggered by cadmium is coupled to phospholipase C via a G protein.Abbreviations BSA
bovine serum albumin
- BK
bradykinin
- [Ca2+]i
cytosolic free calcium
- DME
Dulbecco's modified Eagle's medium
- FBS
fetal bovine serum
- HEPES
4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid
- IC50
concentration that produces 50% inhibition
- PDGF
platelet-derived growth factor
- PSS
physiological salts solution
- SE
standard error of the mean 相似文献
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Xinlei Li Zhengqi Fan Haobo Guo Ning Ye Tao Lyu Wen Yang Jie Wang Jia-Tong Wang Bin Wu Jiyuan Li Hengfu Yin 《Functional & integrative genomics》2018,18(6):659-671
Yellow-flowering species are unique in the genus Camellia not only for their bright yellow pigments but also the health-improving substances in petals. However, little is known regarding the biosynthesis pathways of pigments and secondary metabolites. Here, we performed comparative genomics studies in two yellow-flowered species of the genus Camellia with distinctive flowering periods. We obtained 112,190 and 89,609 unigenes from Camellia nitidissima and Camellia chuongtsoensis, respectively, and identified 9547 gene family clusters shared with various plant species and 3414 single-copy gene families. Global gene expression analysis revealed six comparisons of differentially expressed gene sets in different developmental stages of floral bud. Through the identification of orthologous pairs, conserved and specific differentially expressed genes (DEGs) between species were compared. Functional enrichment analysis suggested that the gibberellin (GA) biosynthesis pathway might be related to the alteration of flowering responses. Furthermore, the expression patterns of secondary metabolism pathway genes were analyzed between yellow- and red-flowered Camellias. We showed that the key enzymes involved in glycosylation of flavonoids displayed differential expression patterns, indicating that the direct glycosylation of flavonols rather than anthocyanins was pivotal to coloration and health-improving metabolites in the yellow Camellia petals. Finally, the gene family analysis of UDP-glycosyltransferases revealed an expansion of group C members in C. nitidissima. Through comparative genomics analysis, we demonstrate that changes of gene expression and gene family members are critical to the variation of natural traits. This work provides valuable insights into the molecular regulation of trait adaptations of floral pigmentation and flowering timing. 相似文献