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Nielsen R Bustamante C Clark AG Glanowski S Sackton TB Hubisz MJ Fledel-Alon A Tanenbaum DM Civello D White TJ J Sninsky J Adams MD Cargill M 《PLoS biology》2005,3(6):e170
Since the divergence of humans and chimpanzees about 5 million years ago, these species have undergone a remarkable evolution with drastic divergence in anatomy and cognitive abilities. At the molecular level, despite the small overall magnitude of DNA sequence divergence, we might expect such evolutionary changes to leave a noticeable signature throughout the genome. We here compare 13,731 annotated genes from humans to their chimpanzee orthologs to identify genes that show evidence of positive selection. Many of the genes that present a signature of positive selection tend to be involved in sensory perception or immune defenses. However, the group of genes that show the strongest evidence for positive selection also includes a surprising number of genes involved in tumor suppression and apoptosis, and of genes involved in spermatogenesis. We hypothesize that positive selection in some of these genes may be driven by genomic conflict due to apoptosis during spermatogenesis. Genes with maximal expression in the brain show little or no evidence for positive selection, while genes with maximal expression in the testis tend to be enriched with positively selected genes. Genes on the X chromosome also tend to show an elevated tendency for positive selection. We also present polymorphism data from 20 Caucasian Americans and 19 African Americans for the 50 annotated genes showing the strongest evidence for positive selection. The polymorphism analysis further supports the presence of positive selection in these genes by showing an excess of high-frequency derived nonsynonymous mutations. 相似文献
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Wisnu Adi Wicaksono Catherine E. Sansom E. Eirian Jones Nigel B. Perry Jana Monk Hayley J. Ridgway 《Symbiosis (Philadelphia, Pa.)》2018,75(1):39-50
Leptospermum scoparium or mānuka is a New Zealand native medicinal plant that produces essential oils with antimicrobial properties. This study investigated the arbuscular mycorrhizal fungi (AMF) community in mānuka by culture dependent (trap culture) and independent (denaturing gradient gel electrophoresis) approaches. Furthermore, to assess whether mycorrhizal inoculation could alter growth and essential oil composition of mānuka, plants of a single regional chemotype were grown in unsterilized soil and inoculated with five AMF isolates. Leaf essential oil compositions and yields were determined by microscale solvent extraction and gas chromatography-mass spectrometry (GC-MS) analysis. AMF inoculation significantly increased growth compared to uninoculated plants. Qualitative i.e. different relative proportions of compounds, which are distinctive in chemotypes and quantitative (i.e. absolute concentrations of compounds, expressed as mg/g of dry leaf or equivalent) effects of AMF inoculation on mānuka essential oil composition depended on the isolate. AMF inoculation modified the Gammaproteobacterial community on roots and this may have contributed to changes in essential oil composition. Overall, these results demonstrated that AMF can improve the growth of mānuka and affect plant secondary metabolites in leaves, which would be valuable in commercial essential oil production from plantation-grown mānuka. 相似文献
225.
Alina Kurolap Anja Armbruster Tova Hershkovitz Katharina Hauf Adi Mory Tamar Paperna Ewald Hannappel Galit Tal Yusif Nijem Ella Sella Muhammad Mahajnah Anat Ilivitzki Dov Hershkovitz Nina Ekhilevitch Hanna Mandel Volker Eulenburg Hagit N. Baris 《American journal of human genetics》2016,99(5):1172-1180
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Adi Hendler Eyal Akiva Mahakaran Sandhu Dana Goldberg Eyal Arbely Colin J Jackson Amir Aharoni 《Molecular biology and evolution》2021,38(2):545
Many enzymes that catalyze protein post-translational modifications can specifically modify multiple target proteins. However, little is known regarding the molecular basis and evolution of multispecificity in these enzymes. Here, we used a combined bioinformatics and experimental approaches to investigate the evolution of multispecificity in the sirtuin-1 (SIRT1) deacetylase. Guided by bioinformatics analysis of SIRT1 orthologs and substrates, we identified and examined important amino acid substitutions that have occurred during the evolution of sirtuins in Metazoa and Fungi. We found that mutation of human SIRT1 at these positions, based on sirtuin orthologs from Fungi, could alter its substrate specificity. These substitutions lead to reduced activity toward K382 acetylated p53 protein, which is only present in Metazoa, without affecting the high activity toward the conserved histone substrates. Results from ancestral sequence reconstruction are consistent with a model in which ancestral sirtuin proteins exhibited multispecificity, suggesting that the multispecificity of some metazoan sirtuins, such as hSIRT1, could be a relatively ancient trait. 相似文献
228.
Uri Hanania Noa Furman-Matarasso Mily Ron Adi Avni 《The Plant journal : for cell and molecular biology》1999,19(5):533-541
Challenging tomato or tobacco varieties with ethylene-inducing xylanase (EIX) from the fungus Trichoderma viride causes rapid induction of plant defence responses leading to programmed cell death. Using the yeast two-hybrid system, we isolated a novel protein, tomato small ubiquitin-related modifier protein (T-SUMO), which specifically interacts with EIX. T-SUMO, a cytoplasmic protein, is a member of the ubiquitin-like protein family. It shows homology to human protein sentrin/SUMO1, which suppresses tumour necrosis factor-induced cell death. Transgenic plants that express T-SUMO in the sense orientation suppress EIX induction of ethylene biosynthesis and cell death, while in the antisense orientation they enhance EIX-induced ethylene biosynthesis. These results indicate that T-SUMO is involved in mediating the signal generated by EIX that leads to induction of plant defence responses. 相似文献
229.
Hystrix javanica is endemic species in Indonesia. Study about fetal development of Hystrix javanica are very rare because of sample limitation. This study was carried out to describe the morphometrics and x-ray analysis of three fetuses in different stage to give basic information about fetal development of Hystrix javanica. Three fetus samples fixed in Bouin’s solution was used in this study. Observation was carried out to identify the characteristic of three fetus samples. This included the pattern of hair, body measurements, body volume, and body weight. X-ray analysis was carried out to know the ossification process in the fetal development. Statistical analysis was carried out using Microsoft 365® Excel program software. Three fetus samples had different specific hair pattern, that was hairless, smooth hairs, and smooth hairs with dense-non dense pattern. Body volume of 1st, 2nd, and 3rd fetus were 23mL, 90mL, and 170mL, respectively. Body weight of 1st, 2nd, and 3rd fetus were 19.5g, 79.22g, and 153.18g, respectively. Pearson’s correlation analysis shown strong relationship between total body length, front body length, back body length, horizontal body diameter, vertical body diameter, head length, and head diameter against body volume and body weight of three fetuses. Significant positive correlation was shown between horizontal body diameter, vertical body diameter, and head diameter against body volume and body length with P value < 0.05. Faint radiopaque images showed in the 2nd fetus sample and strong radiopaque images showed in the 3rd fetus sample. Radiopaque images were identified in the teeth, cranium, vertebrae, and extremities bones. In this study we concluded that there was a specific hair pattern in different fetal stage. All body measurements have positive correlation with body volume and body weight and x-ray analysis shown that the ossification of the bone was started to happen while the smooth hair was growth. 相似文献
230.
F. C. Adi 《BMJ (Clinical research ed.)》1974,1(5900):183-185
This report concerns nine cases of diabetes mellitus associated with infectious hepatitis, an epidemic of which swept through eastern Nigeria between 1970 and 1972. All the patients showed the classical symptoms and signs of diabetes. They quickly responded to treatment, and after a few months the diabetes completely disappeared. Corticosteroid-glucose tolerance tests in four patients 12 to 30 months after the remission of their diabetes were normal. Contact with the remaining five patients had been lost a few months after clinical remission of their diabetes. The infectious hepatitis virus may have damaged pancreatic islet cells to cause an acute remittant form of diabetes mellitus. 相似文献