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81.
mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
相似文献
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84.
乌云伞的解剖学及花粉形态学研究 总被引:3,自引:0,他引:3
八角莲属(Dysosma)是小檗科(Berberidaceae)一个重要属,全国共有7个种,大约分布于北纬23—32°,东经94—122°之间。湖北八角莲属有4个种,其中乌云伞(Dysosma lichuanensis Z. Cheng, sp. nev., ined.)为内定种,是多年生草本,它的形态特征与八角莲(Dysosma 相似文献
85.
86.
Xiaofen Tan Yifan Wen Zhijun Han Xuyang Su Jing Peng Feng Chen Yadong Wang Tianming Wang Changzhong Wang Kelong Ma 《化学与生物多样性》2023,20(2):e202200089
87.
Xue-Yang Wang Zi-Qin Zhao Cheng-Xian Song Zhi-Hao Su Mu-Wang Li Yang-Chun Wu Byung Rae Jin Ming-Jie Deng 《Insect Science》2023,30(3):789-802
The silkworm Bombyx mori L. is a model organism of the order Lepidoptera. Understanding the mechanism of pesticide resistance in silkworms is valuable for Lepidopteran pest control. In this study, comparative metabolomics was used to analyze the metabolites of 2 silkworm strains with different pesticide resistance levels at 6, 12, and 24 h after feeding with fenpropathrin. Twenty-six of 27 metabolites showed significant differences after fenpropathrin treatment and were classified into 6 metabolic pathways: glycerophospholipid metabolism, sulfur metabolism, glycolysis, amino acid metabolism, the urea cycle, and the tricarboxylic acid (TCA) cycle. After analyzing the percentage changes in the metabolic pathways at the 3 time points, sulfur metabolism, glycolysis, and the TCA cycle showed significant responses to fenpropathrin. Confirmatory experiments were performed by feeding silkworms with key metabolites of the 3 pathways. The combination of iron(II) fumarate + folic acid (IF-FA) enhanced fenpropathrin resistance in silkworms 6.38 fold, indicating that the TCA cycle is the core pathway associated with resistance. Furthermore, the disruption of several energy-related metabolic pathways caused by fenpropathrin was shown to be recovered by IF-FA in vitro. Therefore, IF-FA may have a role in boosting silkworm pesticide resistance by modulating the equilibrium between the TCA cycle and its related metabolic pathways. 相似文献
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Frankia菌种保藏 总被引:5,自引:0,他引:5
对用4种方法保藏的Frankia菌,进行了培养物存活、形态及其固氮活性的检测.发现在无氮液体培养基中保藏6年的Frankia.菌丝断裂,孢囊不完整.同期经有氮液体保藏的Frankia菌孢囊较完整.冷冻干燥保藏3.5年和砂管保藏8年,孢囊和菌丝均较完整.上述方法保藏的菌种,经活化后均能生长,且具有典型的Frankia菌形态特征和固氮活性.4种方法比较,无氮液体保藏法的菌体细胞生长速度快,固氮活性强,有侵染结瘤能力. 相似文献