| 1 | Transgenic rhesus monkeys carrying the human MCPH1 gene copies show human-like neoteny of brain development显示文摘Brain size and cognitive skills are the most dramatically changed traits in humans during evolution and yet the genetic mechanisms underlying these human-specific changes remain elusive.Here,we successfully generated 11 transgenic rhesus monkeys(8 first-generation and 3 second-generation)carrying human copies of MCPH1,an important gene for brain development and brain evolution.Brain-image and tissue-section analyses indicated an altered pattern of neural-cell differentiation,resulting in a delayed neuronal maturation and neural-fiber myelination of the transgenic monkeys,similar to the known evolutionary change of developmental delay(neoteny)in humans.Further brain-transcriptome and tissue-section analyses of major developmental stages showed a marked human-like expression delay of neuron differentiation and synaptic-signaling genes,providing a molecular explanation for the observed brain-developmental delay of the transgenic monkeys.More importantly,the transgenic monkeys exhibited better short-term memory and shorter reaction time compared with the wild-type controls in the delayed-matching-to-sample task.The presented data represent the first attempt to experimentally interrogate the genetic basis of human brain origin using a transgenic monkey model and it values the use of non-human primates in understanding unique human traits. | Lei Shi Xin Luo Jin Jiang Yongchang chen Cirong Liu Ting Hu Min Li Qiang Lin Yanjiao Li Jun Huang Hong Wang Yuyu Niu Yundi Shi Martin Styner Jianhong Wang Yi Lu Xuejin Sun Hualin Yu Weizhi Ji Bing Su | 2019 | National Science Review2019，6，3： | 12 |
| 2 | Influence of the biological carbon pump effect on the sources and deposition of organic matter in Fuxian Lake, a deep oligotrophic lake in southwest China显示文摘Biological carbon pumping(BCP)is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matter(AOC).However,the mechanisms underlying BCP and the amount of generated AOC deposited effectively,are still poorly understood.Therefore,we conducted a systematic study combining modern hydrochemical monitoring and a sediment trap experiment in Fuxian Lake(Yunnan,SW China),the second-deepest plateau,oligotrophic freshwater lake in China.Temperature,pH,EC(electrical conductivity),DO(dissolved O2),[HCO3^-],[Ca^2+],SIc,partial CO2(pCO2)pressure,and carbon isotopic compositions of HCO3^-(δ^13CDIc)in water from Fuxian Lake all displayed distinct seasonal and vertical variations.This was especially apparent in an inverse correlation between pCO2 and DO,indicating that variations of hydrochemistry in the lake water were mainly controlled by the metabolism of the aquatic phototrophs.Furthermore,the lowest C/N ratios and highestδ^13Corg were recorded in the trap sediments.Analyses of the C/N ratio demonstrated that the proportions of AOC ranged from 30%to 100%of all OC,indicating that AOC was an important contributor to sedimentary organic matter(OC).It was calculated that the AOC flux in Fuxian Lake was 20.43 t C km^-2 in 2017.Therefore,AOC produced by carbonate weathering and aquatic photosynthesis could potentially be a significant carbon sink and may have an important contribution to solving the lack of carbon sinks in the global carbon cycle. | Haibo He Zaihua Liu Chongying Chen Yu Wei Qian Bao Hailong Sun Yundi Hu Hao Yan | 2019 | Acta Geochimica2019，38，5： | 2 |
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