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Dual roles of the Arabidopsis peat complex in histone H2A deubiquitination and H4K5 acetylation

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Molecular Plant 2023年第11期16卷 1847-1865页

作者： Si-Yao Zheng Bin-Bin Guan Dan-Yang Yuan Qiang-Qiang Zhao Weiran Ge Lian-Mei Tan Shan-Shan Chen Lin Li She Chen Rui-Ming Xu Xin-Jian He College of Life Sciences Beijing Normal UniversityBeijingChina National Institute of Biological Sciences BejingChina National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijingChina School of Life Sciences University of Chinese Academy of SciencesBeijingChina Tsinghua Institute of Multidisciplinary Biomedical Research Tsinghua UniversityBeilingChina

Histone H2A monoubiquitination is associated with transcriptional repression and needs to be removed by deubiquitinases to facilitate gene transcription in eukaryotes.However,the deubiquitinase responsible for genome-wide H2A deubiquitination in plants has yet to be identified.In this study,we found that the previously identified PWWP-EPCR-ARID-TRB(peat)complex components interact with both the ubiquitin-specific protease UBP5 and the redundant histone acetyltransferases HAM1 and HAM2(HAM1/2)to form a larger version of peat complex in Arabidopsis thaliana.UBP5 functions as an H2A deubiquitinase in a nucleosome substrate-dependent manner in vitro and mediates H2A deubiquitination at the whole-genome level in vivo.HAM1/2 are shared subunits of the peat complex and the conserved NuA4 histone acetyltransferase com-plex,and are responsible for histone H4K5 acetylation.Within the peat complex,the PWWP components(PWWP1,PWWP2,and PWWP3)directly interact with UBP5 and are necessary for UBP5-mediated H2A deu-biquitination,while the EPCR components(EPCR1 and EPCR2)directly interact with HAM1/2 and are required for HAM1/2-mediated H4K5acetylation.Collectively,our study not onlyidentifies dual roles of thepeat com-plex in H2A deubiquitination and H4K5 acetylation but also illustrates how these processes collaborate at the whole-genome level to regulate the transcription and development in plants.

关键词： histone H2A deubiquitination H4K5 acetylation UBP5 HAM1 NuA4 peat

Influence of organic amendments on the sorption of pentachlorophenol on soils

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Journal of Environmental Sciences 2009年第4期21卷 474-480页

作者： LI Ruijuan, WEN Bei, ZHANG Shuzhen, PEI Zhiguo, SHAN Xiaoquan State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences,Beijing 100085, China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The influence of pH on the sorption of pentachlorophenol （PCP） onto three organic amendments, char, humic acid （HA） and peat, and the effect of organic amendments on PCP sorption to three kinds of soils were evaluated. The sorption of PCP on these sorbents fitted the Freundlich model well, suggesting that PCP sorption isotherms were nonlinear with exponential coefficient （N） value lower than 1. The PCP sorption capacity on three organic amendments and the N values increased with decreasing pH. The sorption capacities were in the order： char 〉 HA 〉 peat. Organic amendments resulted in an enhancement of sorption capacities of soils. The N values of PCP sorption on soils were decreased by char amendment and increased by HA and peat amendments. This study demonstrated that application of traditional organic amendments led to the enhancement of PCP sorption by soils. This information may aid both in predicting environmental fates of hydrophobic ionizable organic compounds and in developing remediation strategies for them.

关键词： sorption pentachlorophenol char peat humic acid pH

peat humification-and δ^(13)C_(cellulose)-recorded warm-season moisture variations during the past 500 years in the southern Altai Mountains within northern Xinjiang of China

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山地科学学报（英文） 2017年第11期14卷 2200-2211页

作者： ZHANG Dong-liang YANG Yun-peng LAN Bo Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences School of Environmental and Chemical Engineering Chongqing Three Gorges University

To predict future spatio-temporal patterns of climate change, we should fully understand the spatio-temporal patterns of climate change during the past millennium. But, we are not yet able to delineate the patterns because the qualities of the retrieved proxy records and the spatial coverage of those records are not adequate. Northern Xinjiang of China is one of such areas where the records are not adequate. Here, we present a 500-yr land-surface moisture sequence from Heiyangpo peat(48.34°N, 87.18°E, 1353 m a.s.l) in the southern Altai Mountains within northern Xinjiang. Specifically, peat carbon isotope value of cellulose(δ^(13)C_(cellulose)) was used to estimate the warm-season moisture variations and the degree of humification was used to constrain the δ^(13)C_(cellulose)-based hydrological interpretation. The climatic attributions of the interpreted hydrological variations were based on the warm-season temperature reconstructed from Belukha ice core and the warm-season precipitation inferred from the reconstructed Atlantic Multidecadal Oscillations(AMO). The results show that humification decreased and the δ^(13)C_(celluose)-suggested moisture decreased from ~1510 to ~1775 AD, implying that a constant dryingcondition may have inhibited peat decay. Our comparison with reconstructed climatic parameters suggests that the moisture-level decline was most likely resulted from a constant decline of precipitation. The results also show that humification kept a stable level and the δ^(13)C_(celluose)-suggested moisture also decreased from ~1775 to ~2013 AD, implying that peat decay in the acrotelm primarily did not depend on the water availability or an aerobic environment. Again, our comparison with reconstructed climatic parameters suggests that the land-surface moisturelevel decline was most likely resulted from a steady warming of growing-season temperature.

关键词： peat Carbon isotope of cellulose Humifieation Warm-season moisture Southern AltaiMountains

Temperature evolution from the δ ^(18)O record of Hani peat, Northeast China, in the last 14000 years

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Science China Earth Sciences 2009年第5期52卷 952-964页

作者： Shibata YASUYUKI Environmental Chemistry Division National Institute for Environmental Studies Tsukuba

From the last deglaciation to the Holocene, the Greenland Ice Core (GISP2) δ 18O records as well as the records of ice-rafted debris on the surface of the North Atlantic have revealed a succession of sudden cooling events on the centennial to millennial scales. However, the temperature proxy records are rarely studied systematically and directly to ensure that this air temperature cooling pattern simultaneously existed in the East Asian Region, in addition to the repeated pattern occurring in the Greater Atlantic Region. A peat cellulose δ 18O temperature proxy record proximately existing for 14000 years was picked up from the Hani peat in Jilin Province, China. It suggests by comparison that the sudden cooling events, such as the Older Dryas, Inter-Allerφd, Younger Dryas, and nine ice-rafted debris events of the North Atlantic, are almost entirely reiterated in the temperature signals of Hani peat cellulose δ 18O. These cooling events show that the repeatedly occurring temperature cooling pattern not only appeared in the North Atlantic Region in the high latitudes, but also in the Northwest Pacific Region in the middle latitudes. The climate change events marking the start of the Holocene Epoch, the Holocene Megathermal, the "8.2 kyr" event, the "4.2 kyr" event, the Medieval Warm Period, and the Little Ice Age are further discussed. The sensitivity response of Hani peat cellulose δ 18O to the land surface temperature and the reason for the age accuracy of peat cellulose 14C are also discussed based on the characteristics of the peat bog environment.

关键词： Holocene abrupt climate change peat Holocene Megathermal 8.2 kyr event 4.2 kyr event Medieval Warm Period Little Ice Age

peat record reflecting Holo-cene climatic change in the Zoige Plateau and AMS radiocarbon dating

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Chinese Science Bulletin 2002年第1期47卷 66-70页

作者： ZHOU Weijian LU Xuefeng WU Zhengkun DENG Lin A.J.T.Jull D.Donahue W.Beck State Key Lab of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710054China NNSF-AMS Facility University of Arizona

Through the use of reliable AMS dating of high resolution (15-30 years) peat and the establishment of monsoon climate proxies sequence, we have been able to recognize several cold, dry events in the Tibetan Plateau during the Holocene. The more obvious ones occurred around 12800, 11300, 10200, 9580, 8900, 6400, 4400, 3700, 2800 and 1500 cal. aBP. These events correlate well with both ice rafting events recorded in high latitude North Atlantic Ocean sediment cores and cooling events in the low latitude SST. Spectral analysis indicates high frequency climate variation on centennial-millennial time scale during the Holocene. This further reflects Holocene climate instability and the existence of centennial-millenium scale rhythm in mid latitude areas as well.

关键词： Zoige Holocene high-resolution record peat AMS dating climate instability.

Light-induced variation in environmentally persistent free radicals and the generation of reactive radical species in humic substances

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 171-180页

作者： Yafang Shi Yunchao Dai Ziwen Liu Xiaofeng Nie Song Zhao Chi Zhang Hanzhong Jia College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of AgricultureYangling 712100China

Environmentally persistent free radicals(EPFRs)in humic substances play an essential role in soil geochemical processes.Light is known to induce EPFRs formation for dissolved organic matter in aquatic environments;however,the impacts of light irradiation on the variation of EPFRs in soil humic substances remain unclear.In this study,humic acid,fulvic acid,and humin were extracted from peat soil and then in situ irradiated using simulated sunlight.Electron paramagnetic resonance spectroscopy results showed that with the increasing irradiation time,the spin densities and g-factors of humic substances rapidly increased during the initial 20 min and then gradually reached a plateau.After irradiation for 2h,the maximum spin density levels were up to 1.63×10^17,2.06×10^17,and 1.77×10^×10^17 spins/g for the humic acid,fulvic acid,and humin,respectively.And the superoxide radicals increased to 1.05×10^l4-1.46×10^14spins/g while the alkyl radicals increased to 0.47×10^14-1.76×10^14 spins/g.The light-induced EPFRs were relatively unstable and readily returned back to their original state under dark and oxic conditions.Significant positive correlations were observed between the concentrations of EPFRs and reactive radical species(R2=0.65-0.98,/?<0.05),which suggested that the newly produced EPFRs contributed to the formation of reactive radical species.Our findings indicate that under the irradiation humic substances are likely to be more toxic and reactive in soil due to the formation of EPFRs.

关键词： peat Humic substances Environmentally persistent free radicals Light irradiation Reactive radical species

Evolution of vegetation and climate since the last glacial maximum recorded at Dahu peat site, South China

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Science China Earth Sciences 2007年第8期50卷 1209-1217页

作者： XIAO JiaYi Lü HaiBo ZHOU WeiJian ZHAO ZhiJun HAO RuiHui Department of Geographical Science Nanjing Normal UniversityNanjing 210046China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710075China Department of History and Civilization Weinan Normal UniversityWeinan 714000China

Sporopollen analysis on a 346 cm peat record at Dahu, Jiangxi, chronologically constrained by 16 AMS 14C datings, provides an opportunity to reconstruct the vegetation evolution stages responding to cli-mate change in South China since the last glacial maximum. The result shows that during 18330-15630 cal a B.P., broad-leaved forest dominated the area, corresponding to mild, cool and fairly humid climate. At the interval of 15630-11600 cal a B.P., several evergreen broad-leaved species appeared within the broad-leaved forest, indicating moderate and humid condition. During early Holocene, broad-leaved evergreen forest community was constructed as Castanopsis/Lithorcarpus principally developed, suggesting a warm and humid scenario until 6000 cal a B. P. Since 6000 cal a B. P., abrupt forest deterioration happened with an contemporary increase of fern and herb communities, repre-senting a turnover to relatively cool and dry condition and as well, possible impact from human activi-ties. Meanwhile, several relatively cool and dry events can be identified in the sporopollen record, they can be correlated to the North Atlantic Heinrich event, YD and Holocene millennial-scale oscillations, implying that the low latitude climate was coupled with high latitude influences. Moreover, the varia-tions of temperature and humidity since LGM at Dahu were much smaller when compared with the re-cords in north monsoonal China.

关键词： peat site sporopollen analysis paleovegetation paleoenvironment

peat molecular fossils recording paleoclimatic change and organism replacement

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Chinese Science Bulletin 2001年第20期46卷 1749-1752页

作者： XIE Shucheng & R. P. Evershed1. Faculty of Earth Science, China University of Geosciences, Wuhan 430074, China 2. School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK Correspondence should be addressed to Xie Shucheng (e-mail: scxie@ ***) Faculty of Earth Science China University of Geosciences Wuhan China School of Chemistry University of Bristol Bristol

The occurrence of the dominant C23 n-alkane derived from bryophyte was demonstrated to be related to the cold climate, based on the GC and GC/MS analyses on a 40-cm long peat core, in which this compound exponentially varies in abundance with the depth corresponding to the well-known second Little Ice Age. Both the variation of the chemical components of modern bryophyte resulted from climatic change and the ecological data about the biological growth influenced by climate shed light on the point that the variation of this compound in the peat was related to the cold climate. This was also evidenced by the previously-reported lacustrine data. In addition, the variations of the ratios of ketones/esters and C24 n-alkene/n-alkane (C24:1/024:0) display the trend identical with that of organisms, implicating the replacement between bryophyte and monocotyledon occurring in the peat core.

关键词： bryophyte molecular fossil n-alkane paleoclimate Little Ice Age peat lacustrine.

Climate changes in East China since the Late-glacial inferred from high-resolution mountain peat humification records

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Science China Earth Sciences 2009年第1期52卷 118-131页

作者： MA ChunMei ZHU Cheng ZHENG ChaoGui YIN Qian ZHAO ZhiPing School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093China Department of Land Information Engineering Chuzhou CollegeChuzhou 239012China Nanjing Institute of Geography&Limnology Chinese Academy of SciencesNanjing 210008China

High-resolution peat humification records were obtained from Dajiuhu of the Shennongjia Mountains and Qianmutian of the Tianmu Mountains to study climate changes in East China.The analyses of pollen,organic matters,TOC,and Rb/Sr indicate a high degree of peat humification and thus strong decomposition of organic matter when climate was dry.Conversely,when climate was humid,the degree of humification is low because peat was preserved in a waterlogged condition.peat humification from Dajiuhu occurred not only during the Younger Dryas(about 11.4-12.6 cal ka BP),the Blling-Allerd Warm Period(12.6-15.2 cal ka BP),and the Oldest Dryas(about 15.2-16.0 cal ka BP),but also during the early Holocene(about 11.4-9.4 cal ka BP),the 8.2 cal ka BP cold event,and the Holocene Optimum(about 7.0-4.2 cal ka BP).Both peat humification records since nearly 5 ka BP are consistent,showing that mountain peatland has synchronous responses to the East Asia monsoon-induced precipitation.The LOI data confirm the above observation.The monsoon precipitation since nearly 5 ka BP recorded in these two peat profiles can be divided into three phases.During 4.9-3.5 ka BP,precipitation amount was high but fluctuated greatly.During 3.5-0.9 ka BP,precipitation amount was low.During 0.9-0 ka BP,degree of humification reduced gradually,indicating the increase of monsoon precipitation.Contrast to other high-resolution records from East China monsoon region shows that the monsoon precipitation records of the two peat profiles since nearly 16 ka BP are controlled by a common forcing mechanism of summer solar radicalization in the Northern Hemisphere.

关键词： mountain peat the Late-glacial the Holocene degree of humificatiom Dajiuhu of Shennongjia Mountains Qianmutian of Tianmu Mountains climate changes