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The novel male meiosis Recombination regulator coordinates the progression of meiosis prophase Ⅰ

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Journal of Genetics and Genomics 2020年第8期47卷 449-464页

作者： Miao Li Haiwei Feng Zexiong Lin Jiahuan Zheng Dongteng Liu Rui Guo Junshi Li Raymond H.W.Li Ernest H.Y.Ng Michael S.Y.Huen P.Jeremy Wang William S.B.Yeung Kui Liu Shenzhen Key Laboratory of Fertility Regulation Center of Assisted Reproduction and EmbryologyThe University of Hong Kong-Shenzhen HospitalShenzhen518000China Department of Obstetrics and Gynecology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong999077China Department of Biomedical Sciences University of Pennsylvania School of Veterinary MedicinePhiladelphiaPA19104USA School of Biomedical Sciences Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong999077China

Meiosis is a specialized cell division for producing haploid gametes in sexually reproducing organisms.In this study,we have independently identified a novel meiosis protein male meiosis Recombination regulator(MAMERR)/4930432 K21 Rik and showed that it is indispensable for meiosis prophase I progression in male mice.Using super-resolution structured illumination microscopy,we found that MAMERR functions at the same double-strand breaks as the replication protein A and meiosis-specific with OB domains/spermatogenesis associated 22 complex.We generated a Mamerr-deficient mouse model by deleting exons 3 e6 and found that most of Mamerrà/àspermatocytes were arrested at pachynema and failed to progress to diplonema,although they exhibited almost intact synapsis and progression to the pachytene stage along with XY body formation.Further mechanistic studies revealed that the recruitment of DMC1/RAD51 and heat shock factor 2 ebinding protein in Mamerrà/àspermatocytes was only mildly impaired with a partial reduction in double-strand break repair,whereas a substantial reduction in ubiquitination on the autosomal axes and on the XY body appeared as a major phenotype in Mamerrà/àspermatocytes.We propose that MAMERR may participate in meiotic prophase I progression by regulating the ubiquitination of key meiotic proteins on autosomes and XY chromosomes,and in the absence of MAMERR,the repressed ubiquitination of key meiotic proteins leads to pachytene arrest and cell death.

关键词： Meiosis 4930432K21Rik Recombination Ubiquitination

Dependence of limited radiative Recombination rate of InGaN-based light-emitting diode on lattice temperature with high injection

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Chinese Physics B 2020年第4期29卷 488-493页

作者：高江东张建立全知觉刘军林江风益 National Institute of LED on Silicon Substrate Nanchang UniversityNanchang 330096China

It is observed that the radiative Recombination rate in InGaN-based light-emitting diode decreases with lattice temperature increasing.The effect of lattice temperature on the radiative Recombination rate tends to be stable at high injection.Thus,there should be an upper limit for the radiative Recombination rate in the quantum well with the carrier concentration increasing,even under the same lattice temperature.A modified and easily used ABC-model is proposed.It describes that the slope of the radiative Recombination rate gradually decreases to zero,and further reaches a negative value in a small range of lattice temperature increasing.These provide a new insight into understanding the dependence of the radiative Recombination rate on lattice temperature and carrier concentration in InGaN-based light-emitting diode.

关键词： InGaN-based light-emitting diode carrier Recombination ABC-model lattice temperature

Recombination and identification of human alpha B-crystallin

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International Journal of Ophthalmology(English edition) 2018年第12期11卷 1916-1921页

作者： Rui Wang Ze-Hua Chen Yi Wang Hou-Bin Huang Si-Jun Fan Lan-Lan Chen Department of Ophthalmology Hainan Branch of PLA General HospitalSanya 572000Hainan ProvinceChina Chongqing Aier General Hospital Aier School of OphthalmologyCentral South UniversityChongqing 400020 China PLA Rocket Force General Hospital Beijing 100088China

AIM: To recombine the human alpha B-crystallin(αBcrystallin) using gene cloning technology and prokaryotic expression vector and confirm the biological activity of recombinant human αB-crystallin. METHODS: Cloning the human αB-crystallin cDNA according to the nucleotide sequence of the human αBcrystallin, constructing the pET-28/CRYAB prokaryotic expression plasmid by restriction enzyme digestion method, and stably expressing transformed into the Escherichia coli(E. coli) DH5 alpha. The recombinant human αB-crystallin was purified by Q sepharose. By enzyme digestion analysis, Western blotting and sequencing, the recombinant human αB-crystallin was identified and the activity of its molecular protein was detected.RESULTS: Compared with the gene bank(GeneBank), the cloned human sequence of human αB-crystallin cDNA has the same open reading frame. Identification and sequencing of the cloned human αB-crystallin cDNA in prokaryotic expression vector confirmed the full length sequence, and the vector was constructed successfully. The E. coli containing plasmid pET-28/CRYAB induced by isopropyl-β-D-thiogalactoside successfully expressed the human αB-crystallin. Insulin confirmed that the recombinant human αB-crystallin has a molecular chaperone activity. CONCLUSION: The prokaryotic expression vector pET-28/CRYAB of recombinant human αB-crystallin issuccessfully constructed, and the recombinant human αBcrystallin with molecular chaperone activity is obtained, which lay a foundation for the research and application of the recombinant human αB-crystallin and its chaperone activity.

关键词： human alpha B-crystallin gene vector construction identification Recombination

Caseinolytic mitochondrial matrix peptidase X is essential for homologous chromosome synapsis and Recombination during meiosis of male mouse germ cells

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Asian Journal of Andrology 2024年第2期26卷 165-174页

作者： Hai-Wei Feng Yu Zhao Yan-Ling Gao Dong-Teng Liu Li-Jun Huo Key Laboratory of Agricultural Animal Genetics Breeding and ReproductionEducation Ministry of ChinaCollege of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China Shenzhen Key Laboratory of Fertility Regulation Reproductive Medicine CenterThe University of Hong Kong-Shenzhen HospitalShenzhen 518053China Maternal-Fetal Medicine Institute Department of Obstetrics and GynaecologyShenzhen Baoan Women's and Children's HospitalJinan UniversityShenzhen 518100China Department of Obstetrics and Gynaecology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SARChina

Meiosis is the process of producing haploid gametes through a series of complex chromosomal events and the coordinated action of various proteins.The mitochondrial protease complex(ClpXP),which consists of caseinolytic mitochondrial matrix peptidase X(ClpX)and caseinolytic protease P(ClpP)and mediates the degradation of misfolded,damaged,and oxidized proteins,is essential for maintaining mitochondrial homeostasis.ClpXP has been implicated in meiosis regulation,but its precise role is currently unknown.In this study,we engineered an inducible male germ cell-specific knockout caseinolytic mitochondrial matrix peptidase X(Clpx^(cKO))mouse model to investigate the function of ClpX in meiosis.We found that disrupting Clpx in male mice induced germ cell apoptosis and led to an absence of sperm in the epididymis.Specifically,it caused asynapsis of homologous chromosomes and impaired meiotic Recombination,resulting in meiotic arrest in the zygotene-to-pachytene transition phase.The loss of ClpX compromised the double-strand break(DSB)repair machinery by markedly reducing the recruitment of DNA repair protein RAD51 homolog 1(RAD51)to DSB sites.This dysfunction may be due to an insufficient supply of energy from the aberrant mitochondria in Clpx^(cKO) spermatocytes,as discerned by electron microscopy.Furthermore,ubiquitination signals on chromosomes and the expression of oxidative phosphorylation subunits were both significantly attenuated in Clpx^(cKO) spermatocytes.Taken together,we propose that ClpX is essential for maintaining mitochondrial protein homeostasis and ensuring homologous chromosome pairing,synapsis,and Recombination in spermatocytes during meiotic prophase I.

关键词： ClpX homologous chromosome meiosis mitochondrial Recombination synapsis

Inhibition of KU70 and KU80 by CRISPR interference,not NgAgo interference,increases the efficiency of homologous Recombination in pig fetal fibroblasts

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Journal of Integrative Agriculture 2019年第2期18卷 438-448页

作者： LI Guo-ling QUAN Rong WANG Hao-qiang RUAN Xiao-fang MO Jian-xin ZHONG Cui-li YANG Huaqiang LI Zi-cong GU Ting LIU De-wu WU Zhen-fang CAI Geng-yuan ZHANG Xian-wei National Engineering Research Center for Breeding Swine Industry College of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642P.R.China Wens Foodstuff Group Co. Ltd.Yunfu 527400P.R.China

Non-homologous end-joining(NHEJ) is a predominant pathway for the repair of DNA double-strand breaks(DSB). It inhibits the efficiency of homologous Recombination(HR) by competing for DSB targets. To improve the efficiency of HR, multiple CRISPR interference(CRISPRi) and Natronobacterium gregoryi Argonaute(NgAgo) interference(NgAgoi) systems have been designed for the knockdown of NHEJ key molecules, KU70, KU80, polynucleotide kinase/phosphatase(PNKP), DNA ligase IV(LIG4), and NHEJ1. Suppression of KU70 and KU80 by CRISPRi dramatically promoted(P0.05) HR efficiency. Interestingly, although the NgAgoi system significantly suppressed(P0.05) HR efficiency in primary fetal fibroblasts. Our result showed that both NgAgo and catalytically inactive Cas9(dCas9) could interfere with the expression of target genes, but the downstream factors appear to be more active following CRISPR-mediated interference than that of NgAgo.

关键词： homologous Recombination non-homologous end-joining CRISPRi NgAgoi KU70 KU80

Aqueous-processed insulating polymer/nanocrystal solar cells with effective suppression of the leakage current and carrier Recombination

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Chinese Chemical Letters 2020年第6期31卷 1593-1597页

作者： Henan Sun Nannan Chen Yaohua Wang Gan Jin Wei Yuan Haizhu Sun Bai Yang College of Chemistry National Local United Engineering Laboratory for Power Batteries.Northeast Normal UniversityChangchun 130024China College of Material and Chemical Engineering Chuzhou UniversityChuzhou 239000China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

As one of the most environmentally friendly photovoltaic(PV)conversion equipments,aqueousprocessed CdTe nanocrystal solar cells(NC SCs)have attracted great interest in recent years because of their excellent properties such as high charge-carrier mobility and broad absorption.However,two issues including interfacial Recombination and leakage current seriously restrict their performance.In this paper,insulating polymer poly(vinyl pyrrolidone)(PVP)is introduced into CdTe NC SCs to solve the problems.The experimental results of transmission electron microscopy(TEM),atomic force micro scopy(AFM)and dark current measurements,etc.,demonstrate the leakage current is effectively suppressed by introducing PVP.Through further designing device structure,the reduction of interfacial Recombination after introducing PVP is confirmed.By strategically taking the advantages of PVP properties(e.g.,water solubility and thermostability),the power conversion efficiency of the devices with PVP is enhanced by almost 37%compared to pure CdTe devices.This work demonstrates an effective and low-cost method to fabricate NC SCs via aqueous route.Moreover,it also proves that appropriate content of insulating polymer is of beneficial in promoting the PV performance.

关键词： Aqueous-processed Polymer Nanocrystal Recombination Leakage current

Tracking SARS-CoV-2 Omicron diverse spike gene mutations identifies multiple inter-variant Recombination events

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Signal Transduction and Targeted Therapy 2022年第5期7卷 1808-1816页

作者： Junxian Ou Wendong Lan Xiaowei Wu Tie Zhao Biyan Duan Peipei Yang Yi Ren Lulu Quan Wei Zhao Donald Seto James Chodosh Zhen Luo Jianguo Wu Qiwei Zhang Guangdong Provincial Key Laboratory of Virology Institute of Medical MicrobiologyJinan University510632 GuangzhouChina BSL-3 Laboratory(Guangdong) Guangdong Provincial Key Laboratory of Tropical Disease ResearchSchool of Public HealthSouthern Medical University510515 GuangzhouChina Bioinformatics and Computational Biology Program School of Systems BiologyGeorge Mason UniversityManassasVA 20110USA Department of Ophthalmology Howe Laboratory Massachusetts Eye and EarHarvard Medical SchoolBostonMA 02114USA Foshan Institute of Medical Microbiology 528315 FoshanChina

The current pandemic of COVID-19 is fueled by more infectious emergent Omicron variants.Ongoing concerns of emergent variants include possible recombinants,as genome Recombination is an important evolutionary mechanism for the emergence and re-emergence of human viral pathogens.In this study,we identified diverse Recombination events between two Omicron major subvariants(BA.1 and BA.2)and other variants of concern(VOCs)and variants of interest(VOIs),suggesting that co-infection and subsequent genome Recombination play important roles in the ongoing evolution of SARS-CoV-2.Through scanning high-quality completed Omicron spike gene sequences.

关键词： subsequent diverse Recombination

Topological model for Recombination of DNA and RNA

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International Journal of Biomathematics 2018年第8期11卷 35-49页

作者： M. M. El-Sharkasy Department of Mathematics Faculty of Science Tanta University Tanta Egypt sharkasy 78 @yahoo. com

The aim of this paper is to use topological concepts in the construction of flexible mathematical models in the field of biological mathematics. Also, we will build new topographic types to study Recombination of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Finally, we study the topographical properties of constructed operators and the associated topological spaces of DNA and RNA.

关键词： Recombination DNA RNA topology closure limit point and connectedspace

Gate-modulated generation–Recombination current in n-type metal–oxide–semiconductor field-effect transistor

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Chinese Physics B 2014年第12期23卷 550-554页

作者：陈海峰 School of Electronic Engineering Xi'an University of Posts and Telecommunications

Gate-modulated generation–Recombination（GMGR） current IGMGRinduced by the interface traps in an n-type metal–oxide–semiconductor field-effect transistor（n MOSFET） is investigated. The generation current is found to expand rightwards with increasing the reversed drain PN junction bias, and the Recombination current is enhanced as the forward drain bias increases. The variations of IGMGRcurves are ascribed to the changes of the electron density and hole density at the interface, NSand PS, under the different drain bias voltages. Based on an analysis of the physical mechanism, the IGMGR model is set up by introducing two coefficients（m and t）. The coefficients m and t can modulate the curves widths and peak values. The simulated results under reverse mode and forward mode are obviously in agreement with the experimental results. This proves that this model can be applicable for generation current and Recombination current and that the theory behind the model is reasonable. The details of the relevant mechanism are given in the paper.

关键词： generation Recombination interface trap n MOSFET