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Directional selection reduces developmental canalization against genetic and environmental perturbations in Drosophila wings 下载免费PDF全文
Benjamin R. Groth Yuheng Huang Matthew J. Monette John E. Pool 《Evolution; international journal of organic evolution》2018,72(8):1708-1715
Natural selection may enhance or weaken the robustness of phenotypes against genetic or environmental perturbations. However, important aspects of the relationship between adaptive evolution and canalization remain unclear. Recent work showed that the evolution of larger wing size in a high altitude natural population of Drosophila melanogaster was accompanied by decanalized wing development–‐specifically a loss of robustness to genetic perturbation. But this study did not address environmental robustness, and it compared populations that may have numerous biological differences. Here, we perform artificial selection on this same trait in D. melanogaster (larger wing length) and directly test whether this directional selection resulted in decanalization. We find that in general, size‐selected replicates show greater frequencies of wing defects than control replicates both after mutagenesis (genetic perturbation) and when subjected to high temperature stress (environmental perturbation), although the increase in defect frequency varies importantly among replicates. These results support the hypothesis that directional selection may result in the loss of both genetic and environmental robustness–offering a rare window into the relationship between adaptation and canalization. 相似文献
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Shiping Bai Lirong Huang Yuheng Luo Leilei Wang Xuemei Ding Jianping Wang Qiufeng Zeng Keying Zhang 《Biological trace element research》2014,160(3):352-360
To investigate the effects of dietary manganese (Mn) supplementation on iron (Fe) metabolism, a total of 480 50-week-old hens were fed the basal diet (control, 24.35 mg Mn/kg) without Mn supplementation for 6 weeks to reduce Mn storage in the body. Hens were then randomly assigned to one of three treatments, which included the control and control added with 60 or 300 mg Mn/kg diet (M-Mn or H-Mn). Duodenum, heart, liver, and tibia were collected in hens after 12-week feeding period. No significant differences were observed in egg production, feed/egg ratio, shell breaking strength, and shell thickness among different treatments. Compared with control or M-Mn, H-Mn decreased (P?0.05) serum Fe concentration, while increased (P?0.05) total Fe-binding capacity (TIBC). The Fe concentration decreased (P?0.05) in duodenum, and tended to reduce (P?0.10) in liver from control to M-Mn and to H-Mn; whereas, dietary Mn supplementation did not influence (P?>?0.10) Fe concentration in the heart and tibia. In conjunction with reduced Fe retention, DMT1 mRNA expression decreased (P?0.05) with dietary Mn concentration increasing in the duodenum and liver. Duodenal FPN1 mRNA level was higher (P?0.05) in H-Mn group than that in control or M-Mn group, while hepatic FPN1 mRNA expression was lower (P?0.05) in M-Mn or H-Mn group when compared with control. The results demonstrated that dietary Mn supplementation decreased Fe concentration in duodenum and liver of hens, which may be related to the alteration of DMT1 and FPN1 expression in these tissues. 相似文献
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Jin Cheng Sun Yangyang Shi Yuheng Zhang Yuanyuan Chen Kai Li Yuan Liu Guige Yao Fang Cheng Deng Li Jie Zhou Junjie Qu Lianghuan Liu Xianqing Luo Jie 《中国科学:生命科学英文版》2019,62(8):1107-1110
<正>Dear Editor,Branched-chain amino acids (BCAAs) are essential amino acids that must be obtained from the diet for humans and animals. Branched-chain amino acid transaminases (BCATs)catalyze a key step in the BCAA synthesis pathway, however, little is known about their biological roles in planta. In this study, we functionally characterized two BCATs, OsBCAT4 and OsBCAT5, in rice and showed that they regulate 相似文献
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Role of Rhizomys pruinosus as a natural animal host of Penicillium marneffei in Guangdong,China 下载免费PDF全文
Penicillium marneffei, a dimorphic fungus that can cause penicilliosis marneffei, is endemic in Southeast Asia. The only known hosts of P. marneffei are humans and bamboo rats. The aim of our study was to explore the distribution of P. marneffei in bamboo rats, their associated environment and non‐rat‐associated environments. Totally, 270 samples were collected in Guangdong province of China in 2012; the prevalence of P. marneffei was much higher in samples collected from surrounding areas of burrows (8.2%) than in the samples obtained from non‐rat‐associated sites (2%) or artificial farms of bamboo rats (0%). There was no difference in P. marneffei isolated rate from different areas of Guangdong province. The infection is prevalent in all rats, and this fungus could be frequently seen in the rats' lungs. This study confirms that bamboo rat is the ecological niche of P. marneffei and hypothesizes that bamboo rats become infected by inhaling aerosolized conidia originating from environmental sources, rather than by the fecal–oral route or transplacental crossing. According to the result of no detection of P. marneffei in the artificial farm, the activity of bamboo rats might be more relevant to the distribution and dissemination of P. marneffei in natural environment. 相似文献
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乳链菌肽(nisin)抗性机制的研究进展 总被引:5,自引:0,他引:5
乳链菌肽(nisin)是某些乳酸乳球菌产生的一种羊毛硫细菌素。其对包括食品腐败菌和致病菌在内的许多革兰氏阳性菌具有强烈的抑制作用,是目前世界上唯一被允许用作食品添加剂的细菌素。nisin的广泛使用虽未引发大范围的抗性,但在自然界或实验室的选择压力下,某些非nisin产生菌也获得了抵御nisin攻击的抗性机制。nisin抗性机制通常涉及两种方式,即非特异性的生理适应机制和特异性蛋白酶介导的主动防御机制。本文综述了近年来nisin抗性机制的研究进展。 相似文献
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Kehinde Olajide Erinle Zhao Jiang Mengyuan Li Guangxia Su Bingbing Ma Yuheng Ma 《International journal of phytoremediation》2016,18(12):1187-1194
This research presented here, for the first time, elucidates the responses of several antioxidants in Pennisetum leaves exposed to varying concentrations of atrazine (0–200 mgkg?1). Pennisetum has been reported to be resistant to atrazine; however, its physiological response to high concentrations (≥50 mgkg?1) of atrazine is not well documented. The contents of reduced (AsA) and oxidized (DHA) ascorbate increased significantly with increase in atrazine concentration and exposure time; but the increase was more evident under higher (50 and 100 mgkg?1) atrazine concentrations. Increase in atrazine concentration to 200 mgkg?1 significantly decreased AsA, but increased DHA content, throughout the experiment. Seedlings treated with 200 mgkg?1 atrazine showed significantly lowest reduced glutathione (GSH) content, while oxidized glutathione (GSSG) was not significantly affected, after 68 d. Seedlings treated with 100 mgkg?1 atrazine showed increased glutathione-S-transferase (GST) activity after 48 d and 68 d, while treatment with 200 mgkg?1 atrazine significantly increased glutathione reductase (GR) after 58 d. This result suggests that Pennisetum may tolerate lower atrazine concentrations. However, higher concentrations (≥50 mg kg?1), which could have longer residency period in the soil, could induce more physiological damage to the plant. 相似文献
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Ss‐Rhs1, a secretory Rhs repeat‐containing protein,is required for the virulence of Sclerotinia sclerotiorum 下载免费PDF全文
Yang Yu Jifen Xiao Wenjun Zhu Yuheng Yang Jiaqin Mei Chaowei Bi Wei Qian Ling Qing Wanzhong Tan 《Molecular Plant Pathology》2017,18(8):1052-1061
Sclerotinia sclerotiorum is a devastating necrotrophic plant pathogen with a worldwide distribution. Cell wall‐degrading enzymes and oxalic acid are important to the virulence of this pathogen. Here, we report a novel secretory protein, Ss‐Rhs1, which is essential for the virulence of S. sclerotiorum. Ss‐Rhs1 is believed to contain a typical signal peptide at the N‐terminal and eight rearrangement hotspot (Rhs) repeats. Ss‐Rhs1 exhibited a high level of expression at the initial stage of sclerotial development, as well as during the hyphal infection process. Targeted silencing of Ss‐Rhs1 resulted in abnormal colony morphology and reduced virulence on host plants. Microscopic observations indicated that Ss‐Rhs1‐silenced strains exhibited reduced efficiency in compound appressoria formation. 相似文献