Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out cons...Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out conscious migration behavior,adjustment of administrative divisions can be regarded as a quasi-natural experiment.The three cities of Hefei,Wuhu,and Ma'anshan,which are directly related to the adjustment of the administrative division of Chaohu,are taken as the treatment group,and the seven adjacent cities of Lu'an,Huainan,Chuzhou,Bengbu,Anqing,Chizhou,and Tongling are taken as the control group.Differences-in-Differences method and relevant control variables affecting the upgrading of industrial structure are used to test.The test results show that"Partitions of Chaohu"has a significant industrial structure upgrading effect by promoting the optimization of spatial layout,the cross-regional flow of production factors and the effective management of Chaohu Lake Basin.At the same time,the increase of total retail sales of consumer goods,urban fixed assets investment,public utility expenses in science,education,culture and health,and population plays a significant positive role in promoting the upgrading of industrial structure,while foreign direct investment plays a certain inhibition role in the upgrading of industrial structure.In order to meet the ever-developing space demands and enhance the impact on surrounding areas,the Hefei metropolitan area should be driven by technological innovation,strengthen the integration of industrial chains,improve the business environment and transportation network,and continuously promote the upgrading of industrial structure and the formation and development of new productive forces.展开更多
In this work, we present a general theoretical study leading to analytical expression of the seasonal temperature at the near surface that is expected to evaluate any area seasonal temperature of the world using the l...In this work, we present a general theoretical study leading to analytical expression of the seasonal temperature at the near surface that is expected to evaluate any area seasonal temperature of the world using the least square method to fit the hourly data to the theoretical curve of the temperature. It is shown that the temperature is globally the result of two contributions: the contribution of the revolution movement of the terrestrial globe on its elliptical orbit around the sun, the contribution of the spin-orbit coupling for the rotation movement of the terrestrial globe around its polar axis and its revolution movement. The orbital behavior of the temperature is used to find the seasonal divisions of the climate for the local area considered. The whole expression of the temperature is very useful for the meteorological needs. The contribution of the human activities and natural instabilities are the results of discrepancies which increase errors (standard deviations).展开更多
The Belle Corporation is a Chinese domestic shoe maker and seller. It also belongs to an industry that has come to be representative of the ubiquitous "Made in China" label. One of the main reasons the compa...The Belle Corporation is a Chinese domestic shoe maker and seller. It also belongs to an industry that has come to be representative of the ubiquitous "Made in China" label. One of the main reasons the company is favored by global investors is due to its unique business pattern-a pattern that sets manufacturing as its base and is active in exploring industrial chain downstream links and establishing its own individual retail channels. Ever since its first inception in the stock market, Belle has set out to acquire several upstream manufacturing companies, indicating its desire for increasing channel terminals. Using a vertically integrated competition strategy, Belle stands out amongst its rivals as being particularly successful in the non-mainstream manufacturing sector. Consequently, its business practices can be used as a model for other domestic manufacturing companies in their efforts to meet the challenges posed by globalization.展开更多
Angstrom-Prescott equation(AP)is the algorithm recommended by the Food and Agriculture Organization(FAO)of the United Nations for calculating the surface solar radiation(R_(s))to support the estimation of crop evapotr...Angstrom-Prescott equation(AP)is the algorithm recommended by the Food and Agriculture Organization(FAO)of the United Nations for calculating the surface solar radiation(R_(s))to support the estimation of crop evapotranspiration.Thus,the a_(s) and b_(s) coefficients in the AP are vital.This study aims to obtain coefficients a_(s) and b_(s) in the AP,which are optimized for Chinas comprehensive agricultural divisions.The average monthly solar radiation and relative sunshine duration data at 121 stations from 1957-2016 were collected.Using data from 1957 to 2010,we calculated the monthly a_(s) and b_(s) coefficients for each subregion by least-squares regression.Then,taking the observation values of R_(s) from 2011 to 2016 as the true values,we estimated and compared the relative accuracy of R_(s) calculated using the regression values of coefficients a_(s) and b_(s) and that calculated with the FAO recommended coefficients.The monthly coefficients,a_(s) and b_(s),of each subregion are significantly different,both temporally and spatially,from the FAO recommended coefficients.The relative error range(0-54%)of R_(s) calculated via the regression values of the a_(s) and b_(s) coefficients is better than the relative error range(0-77%)of R_(s) calculated using the FAO suggested coefficients.The station-mean relative error was reduced by 1% to 6%.However,the regression values of the a_(s) and b_(s) coefficients performed worse in certain months and agricultural subregions during verification.Therefore,we selected the a_(s) and b_(s) coefficients with the minimum R_(s) estimation error as the final coefficients and constructed a coefficient recommendation table for 36 agricultural production and management subregions in China.These coefficient recommendations enrich the case study of coefficient calibration for the AP in China and can improve the accuracy of calculating R_(s) and crop evapotranspiration based on existing data.展开更多
We say a divisien (S = SA or SB, g) is equal if it divides set S into two subsets SA and SB satisfying f (SA) = f (SB), where f is som attribute function on these sets and SA or SB need not be empty. In the present pa...We say a divisien (S = SA or SB, g) is equal if it divides set S into two subsets SA and SB satisfying f (SA) = f (SB), where f is som attribute function on these sets and SA or SB need not be empty. In the present paper, we have obtained some equal divisions on set of ordered tree with n modes: two equal divisions on tree set; two equal divisions on node set; two divisions on leaf set, one is equal, another one is ''asymptotically'' equal. We conclude that, ordered tree set is on its good behavior in equal dividing.展开更多
Guo Moruo (Kuo Mojo, 1892-1978), specialist in Chinese history, philologist, writer and social activist. His original name was Kuo Kaizhen and his self-styled name was Shangwu. On November 16 1892, he was born in the ...Guo Moruo (Kuo Mojo, 1892-1978), specialist in Chinese history, philologist, writer and social activist. His original name was Kuo Kaizhen and his self-styled name was Shangwu. On November 16 1892, he was born in the town of Shawan in Leshan County, Sichuan Province.From the autumn.of 1907 to the summer of 1913, he was a pupil at the Jiadingfu Middle School and the展开更多
In line with the overall Objectives set out in the"Outline Scheme for the Academic Divisions of theChinese Academy of Sciences (CAS) during theNinth Five-year Plan (1996-2000)," CAS has donea good job of the...In line with the overall Objectives set out in the"Outline Scheme for the Academic Divisions of theChinese Academy of Sciences (CAS) during theNinth Five-year Plan (1996-2000)," CAS has donea good job of the supplementary election of CASmembers and the development of the virtues ofscience and fine style of research. In addihon, con-sultation and appraisal, academic exchanges, andthe popularization of science have progressivelybeen focuses of the academic divisions, and manyaccomplishments have been achieved in these areas.展开更多
The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This pap...The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This paper implements a simple analytical approach in order to generate daily average temperatures which implicitly accounts for surface heating and drivers through a comprehensive representation of station-based temperature records on a universal standard calendar propagated by the earth’s dynamics features. The modeled and observed pattern of daily temperatures exhibits a close agreement with the level of strength agreement exceeding 0.56. The extreme high and low values of the observed temperature patterns are equally well captured although model underestimates the probability of temperatures around the two modal peaks (~25.6℃ and 27.5℃). Additionally, a theoretical thermal-based division led to the identification of six seasons, including two hot and cold periods along with two pairs of mixed hot-cold. The theoretical division proposed here appears to be a good approximation for the understanding of rainfall seasonality in this area.展开更多
The Academic Divisions of the Chinese Academy of Sciences (CAS) are vitally important and integral parts of the academy and were founded in June 1, 1955, six years after the establishment of the CAS. This was an impor...The Academic Divisions of the Chinese Academy of Sciences (CAS) are vitally important and integral parts of the academy and were founded in June 1, 1955, six years after the establishment of the CAS. This was an important event for both the CAS and the Chinese S&T community. The institution, which is composed of the most excellent Chinese scientists, has played an active role in strengthening the academic leadership of China’s S&T undertakings. Over the 40-odd years of ups and downs, the development of Academic Divisions could be characterized by four phases: laying the foundation展开更多
The Resolution on Several Major Issues for Strengthening Socialist Civic Ethics adopted by the Sixth Plenary Session of the Party’s 14th Congress states that "socialist ethics is a major feature of socialist soc...The Resolution on Several Major Issues for Strengthening Socialist Civic Ethics adopted by the Sixth Plenary Session of the Party’s 14th Congress states that "socialist ethics is a major feature of socialist society, a great goal and an important guarantee for the modernization drive.The promotion of socialist morality bears closely on the accomplishment of the grand trans-century plan and the prosperity and development of the socialist cause". To do a good job in enhancing socialist ethics is of great practical importance and profound historical significance to the great cause of building up socialism with its own Chinese characters in the country, to the implementation of the two fundamental changes, and to the enforcement of the development strategy of revitalizing China by science and education and this country’s sustainable develop-展开更多
In January 1984, the Academic Divisions of the CAS,which was established in 1955, held its fifth General Assembly after experiencing 30 years of trials and hardships, marking the beginning of a new period of flourishi...In January 1984, the Academic Divisions of the CAS,which was established in 1955, held its fifth General Assembly after experiencing 30 years of trials and hardships, marking the beginning of a new period of flourishing development.Ten years passed between the fifth assembly and the seventh one,which was held in June 1994.It was in this decade that the Academic Divisions gradually assumed the practice of the international science community according to the domestic situation and international convention by making clear the nature and functions of the Academic Divisions and of their Members, renaming Division Mem-展开更多
On the eve of the 11th General Assembly of the Chinese Academy of Sciences (CAS), the CAS Presidium briefed the press on the important advances achieved by the Academic Divisions (ADs) over the past two years.
The Academic Divisions of the Chinese Academy of Sciences (CAS), the highest advisory body of the State in science and technology, made encouraging progress over the year 2001.
Seismo-tectonic areas of historical strong earthquakes with MS(7 along Xianshuihe-Xiaojiang fault zone are divided, and their individual fault-pattern and tectonic geomorphology are analyzed. Those strong-earthquake a...Seismo-tectonic areas of historical strong earthquakes with MS(7 along Xianshuihe-Xiaojiang fault zone are divided, and their individual fault-pattern and tectonic geomorphology are analyzed. Those strong-earthquake areas are located in some special parts of the fault zone, where the major branch-faults of the fault zone form left stepping, parallel, and fork-like patterns. In the strong-earthquake areas structurally complicated basins are developed, such as pull-apart basins in fork-like area, in double stepping area, and in stepping and fork-like areas.展开更多
The tango of life begins with the very first cell division.New research reveals that to dance their way through development,dividing cells must pass along not just DNA but molecular“memories”that guide their destini...The tango of life begins with the very first cell division.New research reveals that to dance their way through development,dividing cells must pass along not just DNA but molecular“memories”that guide their destinies.When this handoff gets fumbled,the dance falls apart.展开更多
Administrative division is an important means of political power reorganization and management,resource integration and optimal allocation,which profoundly shapes the spatial layout of urban development in China.To cl...Administrative division is an important means of political power reorganization and management,resource integration and optimal allocation,which profoundly shapes the spatial layout of urban development in China.To clarify and compare differences between counties,county-level cities and municipal districts is the primary premise for the study of administrative division and urban development.This paper analyzes the institutional differences between counties and county-level cities,as well as counties,county-level cities and municipal districts,from the aspects of organizational structure,urban construction planning,land management,finance,taxation and public services.The research shows that the establishment of counties,county-level cities and municipal districts adapt to different levels and stages of economic and social development,and the conversion from county to county-level city and the conversion from county(or county-level city)to municipal district are both important transformation ways to change their administrative systems,which has different management system and operation pattern.At the same time,the transformation of county-level administrative region is also a“double-edged sword”,we should think about the administrative system as a whole to decide whether it should be adjusted,and effectively respond to the actual needs of local economic and social development.展开更多
Brassinosteroids are known regulators of meristem activity in Arabidopsis,with low levels being sufficient for normal growth within the proliferating cells of the meristem.Brassinosteroid biosynthesis enzymes are tran...Brassinosteroids are known regulators of meristem activity in Arabidopsis,with low levels being sufficient for normal growth within the proliferating cells of the meristem.Brassinosteroid biosynthesis enzymes are transcriptionally downregulated in response to increased brassinosteroid signaling activity,forming a negative feedback loop to modulate their own expression(Ackerman-Lavert et al.,2021;Vukašinovićet al.,2021).展开更多
R-loops play various roles in many physiological processes,however,their role in meiotic division remains largely unknown.Here we show that R-loops and their regulator RNase H1 are present at centromeres during oocyte...R-loops play various roles in many physiological processes,however,their role in meiotic division remains largely unknown.Here we show that R-loops and their regulator RNase H1 are present at centromeres during oocyte meiotic divisions.Proper centromeric R-loops are essential to ensure chromosome alignment in oocytes during metaphase I(MI).Remarkably,both Rnaseh1 knockout and overexpression in oocytes lead to severe spindle assembly defects and chromosome misalignment due to dysregulation of R-loops at centromeres.Furthermore,we find that replication protein A(RPA)is recruited to centromeric R-loops,facilitating the deposition of ataxia telangiectasia-mutated and Rad3-related(ATR)kinase at centromeres by interacting with the ATR-interaction protein(ATRIP).The ATR kinase deposition triggers the activity of CHK1,stimulating the phosphorylation of Aurora B to finally promote proper spindle assembly and chromosome alignment at the equatorial plate.Most importantly,the application of ATR,CHK1,and Aurora B inhibitors could efficiently rescue the defects in spindle assembly and chromosome alignment due to RNase H1 deficiency in oocytes.Overall,our findings uncover a critical role of R-loops during mouse oocyte meiotic divisions,suggesting that dysregulation of R-loops may be associated with female infertility.Additionally,ATR,CHK1,and Aurora B inhibitors may potentially be used to treat some infertile patients.展开更多
文摘Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out conscious migration behavior,adjustment of administrative divisions can be regarded as a quasi-natural experiment.The three cities of Hefei,Wuhu,and Ma'anshan,which are directly related to the adjustment of the administrative division of Chaohu,are taken as the treatment group,and the seven adjacent cities of Lu'an,Huainan,Chuzhou,Bengbu,Anqing,Chizhou,and Tongling are taken as the control group.Differences-in-Differences method and relevant control variables affecting the upgrading of industrial structure are used to test.The test results show that"Partitions of Chaohu"has a significant industrial structure upgrading effect by promoting the optimization of spatial layout,the cross-regional flow of production factors and the effective management of Chaohu Lake Basin.At the same time,the increase of total retail sales of consumer goods,urban fixed assets investment,public utility expenses in science,education,culture and health,and population plays a significant positive role in promoting the upgrading of industrial structure,while foreign direct investment plays a certain inhibition role in the upgrading of industrial structure.In order to meet the ever-developing space demands and enhance the impact on surrounding areas,the Hefei metropolitan area should be driven by technological innovation,strengthen the integration of industrial chains,improve the business environment and transportation network,and continuously promote the upgrading of industrial structure and the formation and development of new productive forces.
文摘In this work, we present a general theoretical study leading to analytical expression of the seasonal temperature at the near surface that is expected to evaluate any area seasonal temperature of the world using the least square method to fit the hourly data to the theoretical curve of the temperature. It is shown that the temperature is globally the result of two contributions: the contribution of the revolution movement of the terrestrial globe on its elliptical orbit around the sun, the contribution of the spin-orbit coupling for the rotation movement of the terrestrial globe around its polar axis and its revolution movement. The orbital behavior of the temperature is used to find the seasonal divisions of the climate for the local area considered. The whole expression of the temperature is very useful for the meteorological needs. The contribution of the human activities and natural instabilities are the results of discrepancies which increase errors (standard deviations).
文摘The Belle Corporation is a Chinese domestic shoe maker and seller. It also belongs to an industry that has come to be representative of the ubiquitous "Made in China" label. One of the main reasons the company is favored by global investors is due to its unique business pattern-a pattern that sets manufacturing as its base and is active in exploring industrial chain downstream links and establishing its own individual retail channels. Ever since its first inception in the stock market, Belle has set out to acquire several upstream manufacturing companies, indicating its desire for increasing channel terminals. Using a vertically integrated competition strategy, Belle stands out amongst its rivals as being particularly successful in the non-mainstream manufacturing sector. Consequently, its business practices can be used as a model for other domestic manufacturing companies in their efforts to meet the challenges posed by globalization.
基金National High Resolution Earth Observation System(the Civil Part)Technology Projects of ChinaLocal Scientific&Technological Development Projects of Qinghai Guided by Central Government of ChinaDisaster Research Foundation of PICC P&C,No.2017D24-03。
文摘Angstrom-Prescott equation(AP)is the algorithm recommended by the Food and Agriculture Organization(FAO)of the United Nations for calculating the surface solar radiation(R_(s))to support the estimation of crop evapotranspiration.Thus,the a_(s) and b_(s) coefficients in the AP are vital.This study aims to obtain coefficients a_(s) and b_(s) in the AP,which are optimized for Chinas comprehensive agricultural divisions.The average monthly solar radiation and relative sunshine duration data at 121 stations from 1957-2016 were collected.Using data from 1957 to 2010,we calculated the monthly a_(s) and b_(s) coefficients for each subregion by least-squares regression.Then,taking the observation values of R_(s) from 2011 to 2016 as the true values,we estimated and compared the relative accuracy of R_(s) calculated using the regression values of coefficients a_(s) and b_(s) and that calculated with the FAO recommended coefficients.The monthly coefficients,a_(s) and b_(s),of each subregion are significantly different,both temporally and spatially,from the FAO recommended coefficients.The relative error range(0-54%)of R_(s) calculated via the regression values of the a_(s) and b_(s) coefficients is better than the relative error range(0-77%)of R_(s) calculated using the FAO suggested coefficients.The station-mean relative error was reduced by 1% to 6%.However,the regression values of the a_(s) and b_(s) coefficients performed worse in certain months and agricultural subregions during verification.Therefore,we selected the a_(s) and b_(s) coefficients with the minimum R_(s) estimation error as the final coefficients and constructed a coefficient recommendation table for 36 agricultural production and management subregions in China.These coefficient recommendations enrich the case study of coefficient calibration for the AP in China and can improve the accuracy of calculating R_(s) and crop evapotranspiration based on existing data.
基金Supported by China National Natural Science Foundation.
文摘We say a divisien (S = SA or SB, g) is equal if it divides set S into two subsets SA and SB satisfying f (SA) = f (SB), where f is som attribute function on these sets and SA or SB need not be empty. In the present paper, we have obtained some equal divisions on set of ordered tree with n modes: two equal divisions on tree set; two equal divisions on node set; two divisions on leaf set, one is equal, another one is ''asymptotically'' equal. We conclude that, ordered tree set is on its good behavior in equal dividing.
文摘Guo Moruo (Kuo Mojo, 1892-1978), specialist in Chinese history, philologist, writer and social activist. His original name was Kuo Kaizhen and his self-styled name was Shangwu. On November 16 1892, he was born in the town of Shawan in Leshan County, Sichuan Province.From the autumn.of 1907 to the summer of 1913, he was a pupil at the Jiadingfu Middle School and the
文摘In line with the overall Objectives set out in the"Outline Scheme for the Academic Divisions of theChinese Academy of Sciences (CAS) during theNinth Five-year Plan (1996-2000)," CAS has donea good job of the supplementary election of CASmembers and the development of the virtues ofscience and fine style of research. In addihon, con-sultation and appraisal, academic exchanges, andthe popularization of science have progressivelybeen focuses of the academic divisions, and manyaccomplishments have been achieved in these areas.
文摘The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This paper implements a simple analytical approach in order to generate daily average temperatures which implicitly accounts for surface heating and drivers through a comprehensive representation of station-based temperature records on a universal standard calendar propagated by the earth’s dynamics features. The modeled and observed pattern of daily temperatures exhibits a close agreement with the level of strength agreement exceeding 0.56. The extreme high and low values of the observed temperature patterns are equally well captured although model underestimates the probability of temperatures around the two modal peaks (~25.6℃ and 27.5℃). Additionally, a theoretical thermal-based division led to the identification of six seasons, including two hot and cold periods along with two pairs of mixed hot-cold. The theoretical division proposed here appears to be a good approximation for the understanding of rainfall seasonality in this area.
文摘The Academic Divisions of the Chinese Academy of Sciences (CAS) are vitally important and integral parts of the academy and were founded in June 1, 1955, six years after the establishment of the CAS. This was an important event for both the CAS and the Chinese S&T community. The institution, which is composed of the most excellent Chinese scientists, has played an active role in strengthening the academic leadership of China’s S&T undertakings. Over the 40-odd years of ups and downs, the development of Academic Divisions could be characterized by four phases: laying the foundation
文摘The Resolution on Several Major Issues for Strengthening Socialist Civic Ethics adopted by the Sixth Plenary Session of the Party’s 14th Congress states that "socialist ethics is a major feature of socialist society, a great goal and an important guarantee for the modernization drive.The promotion of socialist morality bears closely on the accomplishment of the grand trans-century plan and the prosperity and development of the socialist cause". To do a good job in enhancing socialist ethics is of great practical importance and profound historical significance to the great cause of building up socialism with its own Chinese characters in the country, to the implementation of the two fundamental changes, and to the enforcement of the development strategy of revitalizing China by science and education and this country’s sustainable develop-
文摘In January 1984, the Academic Divisions of the CAS,which was established in 1955, held its fifth General Assembly after experiencing 30 years of trials and hardships, marking the beginning of a new period of flourishing development.Ten years passed between the fifth assembly and the seventh one,which was held in June 1994.It was in this decade that the Academic Divisions gradually assumed the practice of the international science community according to the domestic situation and international convention by making clear the nature and functions of the Academic Divisions and of their Members, renaming Division Mem-
文摘On the eve of the 11th General Assembly of the Chinese Academy of Sciences (CAS), the CAS Presidium briefed the press on the important advances achieved by the Academic Divisions (ADs) over the past two years.
文摘The Academic Divisions of the Chinese Academy of Sciences (CAS), the highest advisory body of the State in science and technology, made encouraging progress over the year 2001.
基金Chinese Joint Seismological Science Foundation (9507424). Contribution No. 2001A003, Institute of Crustal Dynamics, China Seis
文摘Seismo-tectonic areas of historical strong earthquakes with MS(7 along Xianshuihe-Xiaojiang fault zone are divided, and their individual fault-pattern and tectonic geomorphology are analyzed. Those strong-earthquake areas are located in some special parts of the fault zone, where the major branch-faults of the fault zone form left stepping, parallel, and fork-like patterns. In the strong-earthquake areas structurally complicated basins are developed, such as pull-apart basins in fork-like area, in double stepping area, and in stepping and fork-like areas.
文摘The tango of life begins with the very first cell division.New research reveals that to dance their way through development,dividing cells must pass along not just DNA but molecular“memories”that guide their destinies.When this handoff gets fumbled,the dance falls apart.
基金This research was funded by National Natural Science Foundation of China,grant number 41871151.
文摘Administrative division is an important means of political power reorganization and management,resource integration and optimal allocation,which profoundly shapes the spatial layout of urban development in China.To clarify and compare differences between counties,county-level cities and municipal districts is the primary premise for the study of administrative division and urban development.This paper analyzes the institutional differences between counties and county-level cities,as well as counties,county-level cities and municipal districts,from the aspects of organizational structure,urban construction planning,land management,finance,taxation and public services.The research shows that the establishment of counties,county-level cities and municipal districts adapt to different levels and stages of economic and social development,and the conversion from county to county-level city and the conversion from county(or county-level city)to municipal district are both important transformation ways to change their administrative systems,which has different management system and operation pattern.At the same time,the transformation of county-level administrative region is also a“double-edged sword”,we should think about the administrative system as a whole to decide whether it should be adjusted,and effectively respond to the actual needs of local economic and social development.
文摘Brassinosteroids are known regulators of meristem activity in Arabidopsis,with low levels being sufficient for normal growth within the proliferating cells of the meristem.Brassinosteroid biosynthesis enzymes are transcriptionally downregulated in response to increased brassinosteroid signaling activity,forming a negative feedback loop to modulate their own expression(Ackerman-Lavert et al.,2021;Vukašinovićet al.,2021).
基金supported by the National Natural Science Foundation of China(32230029,81925015,32270898,32400709,and 32400714)the National Key Research and Development Program of China(2022YFC2702600)+2 种基金the China Postdoctoral Science Foundation(2024M760638 and 2024M760640)the Science and Technology Project of Guangzhou(2023A03J0886)the plan on enhancing scientific research in GMU.
文摘R-loops play various roles in many physiological processes,however,their role in meiotic division remains largely unknown.Here we show that R-loops and their regulator RNase H1 are present at centromeres during oocyte meiotic divisions.Proper centromeric R-loops are essential to ensure chromosome alignment in oocytes during metaphase I(MI).Remarkably,both Rnaseh1 knockout and overexpression in oocytes lead to severe spindle assembly defects and chromosome misalignment due to dysregulation of R-loops at centromeres.Furthermore,we find that replication protein A(RPA)is recruited to centromeric R-loops,facilitating the deposition of ataxia telangiectasia-mutated and Rad3-related(ATR)kinase at centromeres by interacting with the ATR-interaction protein(ATRIP).The ATR kinase deposition triggers the activity of CHK1,stimulating the phosphorylation of Aurora B to finally promote proper spindle assembly and chromosome alignment at the equatorial plate.Most importantly,the application of ATR,CHK1,and Aurora B inhibitors could efficiently rescue the defects in spindle assembly and chromosome alignment due to RNase H1 deficiency in oocytes.Overall,our findings uncover a critical role of R-loops during mouse oocyte meiotic divisions,suggesting that dysregulation of R-loops may be associated with female infertility.Additionally,ATR,CHK1,and Aurora B inhibitors may potentially be used to treat some infertile patients.
