Genetic behavior of Triticum aestivum–Dasypyrum villosum translocation chromosomes T6V#4S·6DL and T6V#2S·6AL carrying powdery mildew resistance

T6V#2S·6AL and T6V#4S·6DL translocation chromosomes developed from the cross of wheat and different Dasypyrum villosum accessions have good powdery mildew （PM） resistance, but their pairing and pyramiding behavior remains unclear. Results in this study indicated that the pairing frequency rate of the two differently originated 6VS chromosomes in their F1 hybrid was 18.9% according to genomic in situ hybridization （GISH）; the PM resistance plants in the F2 generation from the cross between T6V#4S·6DL translocation line Pm97033 and its PM susceptible wheat variety Wan7107 was fewer than expected. However, the ratio of the resistant vs. the susceptible plants of 15：1 in the F2 generation derived from the cross between the two translocation lines of T6V#2S·6AL and T6V#4S·6DL fitted well. Plants segregation ratio （homozygous：heterozygous：lacking） revealed by molecular marker for T6V#4S·6DL or T6V#2S·6AL in their F2 populations fitted the expected values of 1：2：1 well, inferring that the pairing of the two alien chromosome arms facilitates the transmission of T6V#4S·6DL from the F1 to the F2 generation. A quadrivalent was also observed in 21% of pollen mother cells （PMCs） of homozygote plants containing the two pairs of translocated chromosomes. The chromosome pairing between 6V#2S and 6V#4S indicates that it will be possible to obtain recombinants and clarify if the PM resistance determinant on one alien chromosome arm is different from that on the other.

Genetic Analysis and Molecular Mapping of an All-Stage Stripe Rust Resistance Gene in Triticum aestivum-Haynaldia villosa Translocation Line V3

Triticum aestivum-Hayaldia villosa translocation line V3 has shown effective all-stage resistance to the seven dominant pathotypes of Puccinia striiforms f.sp.tritici prevalent in China.To elucidate the genetic basis of the resistance,the segregating populations were developed from the cross between V3 and susceptible genotype Mingxian 169,seedlings of the parents and F 2 progeny were tested with six prevalent pathotypes,including CYR29,CYR31,CYR32-6,CYR33,Sun11-4,and Sun11-11,F 1 plants and F 3 lines were also inoculated with Sun11-11 to confirm the result further.The genetic studied results showed that the resistance of V3 against CYR29 was conferred by two dominant genes,independently,one dominant gene and one recessive gene conferring independently or a single dominant gene to confer resistance to CYR31,two complementary dominant genes conferring resistance to both CYR32-6 and Sun11-4,two independently dominant genes or three dominant genes（two of the genes show cumulative effect） conferring resistance to CYR33,a single dominant gene for resistance to Sun11-11.Resistance gene analog polymorphism（RGAP） and simple-sequence repeat（SSR） techniques were used to identify molecular markers linked to the single dominant gene（temporarily designated as YrV3） for resistance to Sun11-11.A linkage map of 2 RGAP and 7 SSR markers was constructed for the dominant gene using data from 221 F 2 plants and their derived F 2：3 lines tested with Sun11-11 in the greenhouse.Amplification of the complete set of nulli-tetrasomic lines of Chinese Spring with a RGAP marker RG1 mapped the gene on the chromosome 1B,and then the linked 7 SSR markers located this gene on the long arm of chromosome 1B.The linkage map spanned a genetic distance of 25.0 cM,the SSR markers Xgwm124 and Xcfa2147 closely linked to YrV3 with genetic distances of 3.0 and 3.8 cM,respectively.Based on the linkage map,it concluded that the resistance gene YrV3 was located on chromosome arm 1BL.Given chromosomal location,the reaction patterns and pedigree analysis,YrV3 should be a novel gene for resistance to stripe rust in wheat.These closely linked markers should be useful in stacking genes from different sources for wheat breeding and diversification of resistance genes against stripe rust.

Optimized silicon fertilization regime weakens cadmium translocation and increases its biotransformation in rice tissues

In acidic paddy fields of South China,rice(Oryza sativa L.)faces the dual challenges of cadmium(Cd)toxicity and silicon(Si)deficiency.Although previous studies have highlighted the functions of Si application timing and strategies in mitigating Cd-stressed rice,the precise mechanisms underlying the health restoration of Cd-toxic rice and the assurance of grain safety remain elusive.This study explored Cd translocation and detoxification in the shoots of rice regulated by various Si fertilization regimes:Si(T)(all Si added before transplanting),Si(J)(all Si added at jointing),and Si(TJ)(half Si added both before transplanting and at jointing).The findings revealed that the regime of Si(TJ)was more beneficial to rice health and grain safety than Si(T)and Si(J).The osmotic regulators such as proline,soluble sugars,and soluble proteins were significantly boosted by Si(TJ)compared to other Si treatments,and which enhanced membrane integrity,balanced intracellular pH,and increased Cd tolerance of rice.Furthermore,Si(TJ)was more effective than Si(T)and Si(J)on the Cd sequestration in the cell wall,Cd bio-passivation,and the down-regulated expression of the Cd transport genes.The concentrations of Cd in the xylem and phloem treated with Si(TJ)were reduced significantly.Additionally,Si(TJ)facilitated much more Cd bound with the outer layer proteins of grains,and promoted Cd chelation and complexation by phytic acid,phenolics,and flavonoids.Overall,Si(TJ)outperformed Si(T)and Si(J)in harmonizing the phycological processes,inhibiting Cd translocation,and enhancing Cd detoxification in rice plant.Thereby the split Si application strategy offers potential for reducing Cd toxicity in rice grain.

An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica

Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species.

Effects of Slow-release Nitrogen on Dry Matter Accumulation,Translocation and Yield of Summer Maize

[Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six different treatment were set up:blank control(CK1),slow-release urea 75 kg/hm^(2)(C1),slow-release urea 150 kg/hm^(2)(C2),slow-release urea 225 kg/hm^(2)(C3),slow-release urea 300 kg/hm^(2)(C4)and ordinary urea 300 kg/hm^(2)(CK2),to study the change law of dry matter accumulation and translocation in summer maize.[Results]Treatment slow-release urea 225 kg/hm^(2)(C4)showed summer maize yield,dry matter translocation between organs,grain contribution rate and proportion of grain dry matter in the full ripe stage higher than other treatments.Considering the weight loss and cost factors,slow-release urea 225 kg/hm^(2)(C3)could be recommended as the fertilizing amount for summer maize.[Conclusions]This study provides theoretical reference for rational selection of fertilizers for reducing fertilizer application and increasing fertilizer efficiency,and for production of summer maize in Shajiang black soil region.

Molecular cytogenetic analyses of two new wheat-rye 6RL translocation lines with resistance to wheat powdery mildew

Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye derivatives,designated JS016 and JS110,were produced by crossing common wheat cultivar Yangmai 23 with Pakistani rye accession W2A.Using sequential genomic in situ hybridization(GISH)and multicolor fluorescence in situ hybridization(mc-FISH),JS016 and JS110 were identified as a T6BS.6RL translocation line and a T6BS.6BL6RL translocation line,respectively.Ten newly 6RL chromosome arm-specific markers were developed and used to confirm the 6RL translocation.The wheat 55K single-nucleotide polymorphism(SNP)array further verified the molecular cytogenetic identification results above and clarified their breakpoints at 430.9 and 523.0 Mb of chromosome 6B in JS016 and JS110,respectively.Resistance spectrum and allelism test demonstrated that JS016 and JS110 possessed novel powdery mildew resistance gene(s)that was derived from the 6RL translocation but differed from Pm20.Moreover,JS016 and JS110 had better agronomic traits than the previously reported 6RL translocation line carrying Pm20.To efficiently transfer and detect the 6RL translocation from JS016 and JS110,one 6RL-specific Kompetitive allele specific PCR(KASP)marker was developed and validated in high throughput marker-assisted selection(MAS).

Interaction between diet and genetics in patients with inflammatory bowel disease

In this editorial,we comment on the article by Marangoni et al,published in the recent issue of the World Journal of Gastroenterology 2023;29:5618-5629,about“Diet as an epigenetic factor in inflammatory bowel disease”.The authors emphasized the role of diet,especially the interaction with genetics,in promoting the inflam-matory process in inflammatory bowel disease(IBD)patients,focusing on DNA methylation,histone modifications,and the influence of microRNAs.In this editorial,we explore the interaction between genetics,gut microbiota,and diet,in an only way.Furthermore,we provided dietary recommendations for patients with IBD.The Western diet,characterized by a low fiber content and deficiency the micronutrients,impacts short-chain fatty acids production and may be related to the pathogenesis of IBD.On the other hand,the consumption of the Mediter-ranean diet and dietary fibers are associated with reduced risk of IBD flares,particularly in Crohn’s disease(CD)patients.According to the dietary guidance from the International Organization for the Study of Inflammatory Bowel Diseases(IOIBD),the regular consumption of fruits and vegetables while reducing the consumption of saturated,trans,dairy fat,additives,processed foods rich in maltodextrins,and artificial sweeteners containing sucralose or saccharine is recommended to CD patients.For patients with ulcerative colitis,the IOIBD recommends the increased intake of natural sources of omega-3 fatty acids and follows the same restrictive recommendations aimed at CD patients,with the possible inclusion of red meats.In conclusion,IBD is a complex and hetero-geneous disease,and future studies are needed to elucidate the influence of epigenetics on diet and microbiota in IBD patients.

A Theory of Bio-Quantum Genetics

The physical mechanism of heredity or inheritance of genes is a quantum mechanical and/or quantum computational process. A theory of bio-quantum genetics is established in this paper. Principle of Bio-quantum Genetics is suggested. I propose and define the soft-genes of genetics controlling the processes of heredity or inheritance of genes. This research deals with the quantum mechanisms of Mendel plant heredity and family inheritance as examples of bio-quantum genetics, deepening our understanding of heredity or inheritance. I believe that more contributions will be made to promote researches of bio-quantum genetics or quantum biology at large.

CGH-based microarray detection of cryptic and novel copy number alterations and balanced translocations in cytogenetically abnormal cases of b-cell all

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children, with the majority of cases being of precursor B-cell phenoltype. Conventional cytogenetic analysis plays an important role in the diagnosis of B-cell ALL, identifying characteristic chromosomal abnormalities associated with a given prognosis therein facilitating optimized treatment. The more recent introduction of microarray technology to the analysis of B-cell ALL has afforded both higher resolution for the detection of known abnormalities and an ability to identify novel copy number abnormalities (CNAs) with potential clinical relevance. In the current study, microarray analysis was performed on 20 cytogenetically abnormal B-cell ALL cases (10 pediatric and 10 adult), while a novel microarray-based balanced-translocation detection methodology (translocation CGH or tCGH) was applied to that subset of cases with a known or suspected recurrent balanced translocation. Standard microarray analysis identified that CNAs was not detected by previous conventional cytogenetics in 75% (15/20) cases. tCGH identified 9/9 (100%) balanced translocations defining BCR/ABL1 (x4), ETV6/RUNX1 (x3), and MLL/AFF1 (x2) breakpoints with high resolution. The results illustrate the improved molecular detail afforded by these technologies and a comparison of translocation breakpoints, CNAs and patient age offers new insights into tumor biology with potential prognostic significance.

Genetic effects of Agropyron cristatum 2P chromosome translocation fragments in a wheat background

Agropyron cristatum(2n=4x=28,PPPP)is a wild relative of common wheat which contains a large number of desirable genes that can be exploited for wheat improvement.Wheat–A.cristatum 2P alien translocation lines exhibit many desirable traits,such as small flag leaves,a high spikelet number and density,and a compact plant type.An agronomic trait evaluation and a genetic analysis were carried out on translocation lines and backcross populations of these lines carrying different translocation fragments.The results showed that a translocation fragment from 2PT-3(2PL)reduced the length of the flag leaves,while translocation fragments from 2PT-3(2PL)and 2PT-5(2PL(0.60–1.00))reduced the width of the flag leaves.A translocation fragment from 2PT-13(2PS(0.18–0.36))increased the length and area of the flag leaves.Translocation fragments from 2PT-3(2PL)and 2PT-8(2PL(0.86–1.00))increased the density of spikelets.Translocation fragments from 2PT-7(2PL(0.00–0.09)),2PT-8(2PL(0.86–1.00)),2PT-10(2PS),and 2PT-13(2PS(0.18–0.36))reduced plant height.This study provides a scientific basis for the effective utilization of wheat–A.cristatum translocation lines.

The Practice and Exploration of Applying EBM to Bilingual Teaching of Medical Genetics at OSBCM

In the process of teaching medical genetics of undergraduate clinical medicine, the practice and exploration of applying EBM to the bilingual teaching of OSBCM medical genetics are carried out. Using CBL and PBL as the carrier can make up for the shortcomings of a single teaching mode, synthesize the advantages of multiple teaching modes. It starts from integrating the basic theoretical knowledge of medicine and clinical practice knowledge, improving students’ bilingual level of medical genetics, cultivating students’ literature retrieval ability, and promoting early clinical, multi-clinical and repeated clinical consciousness for medical students. Therefore, it is more conducive to cultivate students’ ability to learn independently, accurately analyze and solve problems, improve medical students’ clinical thinking ability and scientific research awareness, improve medical students’ ability of international communication, and lay a solid foundation for improving medical students’ future post competence, innovative spirit and lifelong learning ability.

Trisomy 21 with t(5; 11) Chromosomal Translocation as New Unfavorable Cytogenetic Abnormalities in Pediatric Acute Myeloid Leukemia Type M2: One Case Report of Nine-year Follow-up and Literature Review

We report one case of pediatric acute myeloid leukemia type 2（AML-M2） who presented with karyotypic aberration of trisomy 21 with the t（5;11） chromosomal translocation. The patient achieved complete remission after two cycles of chemotherapy of daunorubicin, cytarabine and etoposide. Then, follow-up cytogenetic analysis from bone marrow cell cultures demonstrated a normal karyotype of 46, XY. After 9 years, the patient relapsed and the karyotypic abnormalities of trisomy 21 with t（5;11） reappeared. It was concluded that trisomy 21 with t（5; 11） is a new unfavorable cytogenetic aberration in AML-M2.

Identification of Triticum aestivum-Haynaldia villosa Translocation Line T6BS·6BL-2VS

[Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum aestivum)-Haynaldia villosa disomic substitution line and common wheat Nonglin26-3C chromosome of Aegilops triuncialis disomic addition line,the analysis methods such as chromosome C-banding,genomic in situ hybridization and molecular marker technique were comprehensively applied and combined characters investigation.[Result] The wheat-Haynaldia villosa translocation line(T6BS·6BL-2VS)was selected from hybrid progenies to conduct characters investigation,which found some bristles on glume ridge of T6BS·6BL-2VS.[Conclusion] The translocation line induced by gametocidal chromosome was a small segment translocation line and the gene of bristle on glume ridge of Haynaldia villosa was located between the middle and the terminal of 2VS.

Fruit Photosynthesis and Assimilate Translocation and Partitioning: Their Characteristics and Role in Sugar Accumulation in Developing Citrus unshiu Fruit

Dynamics of dry- or fresh-weight of fruit, peel photosynthetic rate and chlorophyll content, and the characteristics of translocation and distribution of radiolabelled assimilates from leaf or fruit were examined in developing satsuma mandarin (Citrus unshiu Marc. cv. Miyagawa wase) fruit from primary stage of fruit enlargement up to fruit full ripe. Change in fruit photosynthetic rate was some what related to the change in the chlorophyll content of peel. Fruit photosynthetic rate markedly declined as chlorophyll degradation occurred in the peel. Before full ripe stage of the fruit, photosynthates produced by a 14C-fed leaf were mainly distributed to juice sacs even during periods when dry matter accumulation in peel was more rapid than that in juice sacs. At the full ripe stage, peel photosynthetic rate approached zero and peel became the major sink of leaf photosynthates. Most of the peel assimilates, however, remained in situ for up to 48 h after feeding 14CO 2 to the fruit, only a small portion being transported to other parts of fruit. The percentage of fruit photosynthates exported decreased with fruit development and ripening, but the peak rate of export to juice sacs amount to as high as 12%. The sugar content and dry weights of peel and juice sacs in shaded fruit were lower than that in the control fruit. These results show that peel assimilate was mainly consumed in peel respiration and growth and thus the dependence on leaf photosynthates decreased. Part of this assimiate was used in sugar accumulation in juice sacs of fruit.

Translocation and Distribution of Imidacloprid in Tobacco with Two Application Methods

[Objective] To compare the translocation and distribution of imidacloprid in tobacco with spray and root irrigation application methods. [Methods] Pot experiment in the greenhouse was carried out, and LC-MSMS was used to determine the con- tent of imidacloprid in different parts of tobacco plants （roots, stems, the upper, middle and lower leaves） at different time. [Results] The imidacloprid could be absorbed by root and could be transported to all parts of the tobacco plant after irrigating root, but the original deposition amount was larger and the transport efficiency was lower after spraying. [Conclusion] The translocation and distribution of imidacloprid by spraying was more uniform and the holding efficiency was better, but imidacloprid with root irrigation could act on leaf directly, and had better readily availability.

A Preliminary Study on Conservation Genetics of Three Endangered Orchid Species

采用随机扩增多态DNA(RAPD)分析研究了中国 3种珍稀濒危兰科植物硬叶兜兰 (PaphiopedilummicranthumTangetWang)、麻栗坡兜兰 (P .malipoenseS .C .ChenetTsi)和独花兰 (ChangnieniaamoenaChien)的遗传多样性与群体遗传结构。 12个RAPD引物在 2种兜兰中共扩增出 131条带。对 4个硬叶兜兰群体的检测表明其物种水平的多态条带百分率 (PPB)为 71.6 % ,Nei的基因多样度 (h)为 0 .2 171,Shannon多样性指数 (I)为 0 .330 1;4个群体的平均多样性水平为PPB =45 .2 % ,h =0 .145 7,I =0 .2 2 0 4,低于远交兰花的平均水平。在总遗传变异中 ,群体间遗传变异占 2 0 .31% ,略高于远交物种的平均水平。在物种水平上 ,麻栗坡兜兰的PPB为 49.5 % ,h为 0 .1174,I为0 .176 4,均大大低于硬叶兜兰。对 11个独花兰群体采用 16个RAPD引物共扩增出 119条带。物种水平PPB =76 .5 % ,h =0 .1941,I=0 .30 5 8;在群体水平上 ,上述 3个指标的平均值则分别为 37.2 %、0 .1197和 0 .1810 ,均低于远交兰花的平均水平。群体间的遗传变异占 45 .2 7% ,遗传分化明显高于远交物种的平均水平。导致 3个物种遗传多样性偏低而群体间遗传分化较高的主要原因在于人为的过度采挖和生境的片断化。

Polymorphisms of CMYA3 Gene in 13/17 Robertsonian Translocation Pigs

[Objective] The aim was to study the polymorphism of CMYA3 gene in the 148 pigs of hybrid offspring of 13/17 Robertsonian translocation pigs [2n = 37,rob （13;17）] intercrossing.[Method] PCR-RFLP method was adopted.[Result] A 507 bp fragment of CMYA3 gene was obtained by PCR amplification,and then amplification product by using restriction nuclease Bsh1236Ⅰ was detected by agarose gel electrophoresis.As a result,both alleles （A and B） of the loci were found in the population.The frequencies of allele A and B were 0.699 and 0.301.The genotype frequencies of AA,AB and BB were 0.615,0.169 and 0.216.The frequencies of allele A and genotype AA were significantly higher than allele B and genotype BB in populations.[Conclusion] The study will provide theoretical basis for molecular breeding and marker-assisted selection of 13/17 Robertsonian translocation pigs.

A Preliminary Study on Conservation Genetics of Endangered Vatica guangxiensis (Dipterocarpaceae)

运用 2 0个 10碱基随机引物 ,对中国龙脑香科 (Dipterocarpaceae)特有的珍稀濒危植物版纳青梅 (VaticaguangxiensisX .L .Mo)进行了RAPD多态性分析。 3个自然居群和 1个迁地保护居群 (分布于云南和广西 )共扩增出2 31个位点 ,多态位点所占比例 (PPB)为 5 3.6 8% ;观察等位基因数na =1.5 36 8,有效等位基因数ne =1.2 878,Nei基因多样性指数h为 0 .16 86 ,居群内的遗传多样性水平较低。基于AMOVA和POPGENE的结果均表明居群内的遗传变异大于居群间的遗传变异。居群内的遗传变异为 5 5 .0 9% ,居群间的变异为 44 .91% (AMOVA) ;基因分化系数Gst为 0 .3746 (POPGENE) ,表明居群间存在高水平的遗传分化。研究结果对该濒危植物的保护有重要意义。考虑到低水平的遗传多样性和高水平的居群分化 ,通过居群间种子和幼苗的交换来促进基因流是可行的保护方案。迁地保护居群 (ML)不具最高的遗传多样性 ,表明为了保护此濒危物种的全部遗传变异 。

Meiotic Behavior of 1BL/1RS Translocation Chromosome and Alien Chromosome in Two Tri-genera Hybrids

The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivision of translocation chromosome at anaphase I and rye chromatin micronucleus at tetrad stage were observed, A plant with one normal 1BL/1RS translocation chromosome and one 1BL/1RS translocation chromosome deleted about 1/3 of rye chromosome arm in length was identified. One plant with wheat-Thinopyrum non-Robertson translocation chromosome was also detected in the F-2 population of Yi4212 x Yi4095. That could be the results of unequal misdivision of wheat-rye 1BL/1RS translocation chromosome and Thinopyrum chromosome during meiosis. No interaction between translocation chromosome and alien chromosome at meiosis was supported by the data of the distribution frequencies of translocation chromosome and Thinopyrum or Haynaldia chromosome in the progeny of two hybrids. The results may be useful to cultivate new germplasms with different length of rye 1R short arm and wheat-alien non-Robertson translocation tines under wheat background.

基因组Translocation排序问题的改进多项式算法

该文给出基因组 Translocation排序问题的一个改进多项式算法 .原算法所用存储空间为 O(n) ,时间复杂度为 O(n3) .文中改进算法仍采用 O(n)存储空间 ,时间复杂度为 O(n2 logn) .具体地 ,将计算 Translocation距离的时间复杂度由 O(n3)改进为 O(n2 ) ,将计算 Translocation序列的时间复杂度由 O(n3)改进为 O(n2 logn) .