Genetic relationship of interspecies for eight birch species

Genetic relationships of eight species of genus Betula were evaluated using ISSR marks. A total of 236 loci were generated from 17 ISSR primers. Percentage of polymorphic bands (PPB) varied from 5.93 to 19.92. The highest and the lowest level of genetic differentiation were detected in B. ovalifolia and B. maximowicziana Regel respectively. In these eight species, genetic diversity of birch (HT) was 24.38 %, and the genetic variation (GST ) interspecies was accounting for 79.36% of total genetic variation. According to the cluster results of genetic distance, the eight species were classified into three groups as B. davurica, B. ovalifolia, B. platyphylla and B. pendula for one group; B. schmidtii, B. costata and B. ermanii Cham. var. communis for one group, and B. maximowicziana Regel for another group. The result of cluster is consistent with traditional morphological classification.

Multispecies communities:interspecies interactions influence growth on saliva as sole nutritional source

Human oral bacteria live in multispecies communities in the biofilm called dental plaque. This review focuses on the interactions of seven species and the ability of each species individually and together with other species to grow on saliva as the sole source of nutrient. Community formation in biofihns in flow cells is monitored using species-specific fluorophore-conjugated immunoglobulin Gy and images are captured by confocal microscopy. Early colonizing veillonellae emerge from this review of interspecies interactions in saliva as a critical genus that guides the development of multispecies communities. Highly selective interspecies recognition is evident as initial colonizers pair with early and middle colonizers to form multispecies communities that grow on saliva.

Controlling the Collision Between Two Solitons in a Two-Component Condensate by Interspecies Interactions

We present a family of the solutions of two-component Bose-Einstein condensates with time-dependentscattering length by means of multiple-scale method.Our numerical calculations show that the collision properties (theposition,the time,and the frequency of the collision) between two solitons can be controlled by the time-dependentinterspecies scattering length.Meanwhile,we also find that the amplitude of the solitons is close related to the timedependentinterspecies scattering length.

Serial Nuclear Transfer of Goat-Rabbit Interspecies Reconstructed Embryos

The experiments of serial nuclear transfer were conducted between Boer goat and rabbit. The enucleated oocytes of rabbit were used as recipients while the blastomeres of goat morula was used as nuclear donor. The reconstructed embryos developing to morula were used as donor for serial cloning. As a result, two generations of reconstructed embryos were obtained, including 58 first generation reconstructed embryos and 14 second generation reconstructed embryos. The fusion rates were 79.5 and 70%, respectively, and there was no significant difference between them （P〉0.05）. The cleavage rates were 75.9 and 28.6% respectively with significant difference （P〈0.01）. No blastocyst was obtained from the second generation reconstructed embryos while 13.8% of first generation reconstructed embryos developed to blastocyst.

The nucleoside antiviral prodrug remdesivir in treating COVID-19 and beyond with interspecies significance

Infectious pandemics result in hundreds and millions of deaths,notable examples of the Spanish Flu,the Black Death and smallpox.The current pandemic,caused by SARS-CoV-2(severe acute respiratory syndrome coronavirus 2),is unprecedented even in the historical term of pandemics.The unprecedentedness is featured by multiple surges,rapid identification of therapeutic options and accelerated development of vaccines.Remdesivir,originally developed for Ebola viral disease,is the first treatment of COVID-19(Coronavirus disease 2019)approved by the United States Food and Drug Administration.As demonstrated by in vitro and preclinical studies,this therapeutic agent is highly potent with a broad spectrum activity against viruses from as many as seven families even cross species.However,randomized controlled trials have failed to confirm the efficacy and safety.Remdesivir improves some clinical signs but not critical parameters such as mortality.This antiviral agent is an ester/phosphorylation prodrug and excessive hydrolysis which increases cellular toxicity.Remdesivir is given intravenously,leading to concentration spikes and likely increasing the potential of hydrolysis-based toxicity.This review has proposed a conceptual framework for improving its efficacy and minimizing toxicity not only for the COVID-19 pandemic but also for future ones caused by remdesivir-sensitive viruses.

An Interspecies Conserved Antigen of Plasmodium falciparum Containing Clusters of Asparagine Residues

An interspecies conserved Plasmodium asparagine rich antigen, designated as ARK26, was isolated by immunoscreening P.falciparum genomic DNA expression library with mouse convalescent anti P.yeolii serum. Partial DNA sequence analysis reveals that ARK26 contains clusters of asparagines and no randomly repeated amino acid sequence motifs are observed. A 65 ×10 3 GST fusion protein is expressed by recombinant plasmid PGEX 5X 1(ARK26) in E.coli C strain ABLE K. Computer programs predict that two asparagine rich regions are among the possible antigenic epitopes of p37 encoded by ARK26. Interestingly, the sequence of ARK26 displays significant similarity to yeast and several other species' mitochondrial genes, and its possible function is discussed.

Interspecies transmission and host restriction of avian H5N1 influenza virus

Long-term endemicity of avian H5N1 influenza virus in poultry and continuous sporadic human infections in several countries has raised the concern of another potential pandemic influenza. Suspicion of the avian origin of the previous pandemics results in the close investigation of the mechanism of interspecies transmission. Entry and fusion is the first step for the H5N1 influenza virus to get into the host cells affecting the host ranges. Therefore receptor usage study has been a major focus for the last few years. We now know the difference of the sialic acid structures and distributions in different species, even in the different parts of the same host. Many host factors interacting with the influenza virus component proteins have been identified and their role in the host range expansion and interspecies transmission is under detailed scrutiny. Here we review current progress in the receptor usage and host factors.

Domesticated cynomolgus monkey embryonic stem cells allow the generation of neonatal interspecies chimeric pigs

Blastocyst complementation by pluripotent stem cell(PSC)injection is believed to be the most promising method to generate xenogeneic organs.However,ethical issues prevent the study of human chimeras in the late embryonic stage of development.Primate embryonic stem cells(ESCs),which have similar pluripotency to human ESCs,are a good model for studying interspecies chimerism and organ generation.However,whether primate ESCs can be used in xenogenous grafts remains unclear.In this study,we evaluated the chimeric ability of cynomolgus monkey(Macaca fascicularis)ESCs(cmESCs)in pigs,which are excellent hosts because of their many similarities to humans.We report an optimized culture medium that enhanced the anti-apoptotic ability of cmESCs and improved the development of chimeric embryos,in which domesticated cmESCs(D-ESCs)injected into pig blastocysts differentiated into cells of all three germ layers.In addition,we obtained two neonatal interspecies chimeras,in which we observed tissue-specific D-ESC differentiation.Taken together,the results demonstrate the capability of D-ESCs to integrate and differentiate into functional cells in a porcine model,with a chimeric ratio of 0.001-0.0001 in different neonate tissues.We believe this work will facilitate future developments in xenogeneic organogenesis,bringing us one step closer to producing tissue-specific functional cells and organs in a large animal model through interspecies blastocyst complementation.

Redox-active humics support interspecies syntrophy and shift microbial community

The network of microbial electron transfer can establish a syntrophic association of microbes by connecting interspecies metabolisms, and a variety of redox-active shuttles in environment have been proved to accelerate the electron flow in a microbial community. Using humic substances as models, we investigated how different redox-active shuttles with different electrochemical properties influence interspecies electron transfer, and affect the shift of microbial communities. The co-culture of two species was constructed with supplements of humics, and the electron transfer between these two strains was found to be linked by humic acid with a wider window of redox potential and multi-peaks of redox reactions. Based on the shift of microbial composition, the humic substances with a wide potential window and multi-peaks of redox reactions for accepting and donating electrons could increase the biodiversity(Chao 1 and phylogenetic diversity) with a large extent. The mechanism by which redox-active shuttles mediate the microbial electron transfer network could facilitate our understanding of syntrophic interactions between microbes.

Microsatellite DNA analysis proves nucleus of interspecies reconstructed blastocyst coming from that of donor giant panda

A method for DNA isolation from early development of blastocyst and further analysis of nuclear and mitochondrial DNA was developed in present study. Total DNA was prepared from interspecies reconstructed blastocyst and a giant panda specific microsatellite locus g010 was successfully amplified. DNA sequencing of the PCR product showed that two sequences of reconstructed blastocysts are the same as that of positive control giant panda. Our results prove that the nucleus of interspecies reconstructed blastocyst comes from somatic nucleus of donor giant panda.

Serial nuclear transfer improves the development of interspecies reconstructed giant panda (Aluropoda melanoleucd) embryos

Interspecies somatic nuclear transfer (NT) may provide a new approach for preservation of the endangered rare species. Previous interspecies cloning studies have shown that a nucleus from a quiescent somatic cell supports early development of reconstructed embryos in the ooplasm from another species. In this study, we transferred nonqui-escent somatic cells from a giant panda into the perivitelline space of the enucleated rabbit oocytes. After electrofusion (at the rate of 71.6%) and electrical activation, 4.2% of the panda-rabbit reconstructed embryos developed to blastocyst in vitro. For improving the development rate of reconstructed embryos, we used serial NT in this study, i.e. blas-tomeres from reconstructed morulae were transferred into the perivitelline space of the enucleated rabbit oocytes. The fusion rates in the groups of serial I, serial Ⅱ and serial Ⅲ were 79.5%, 84.1% and 78.0%, respectively, having no difference with that of somatic group. And the blastocyst rates in serial NT groups

Different outer membrane c‐type cytochromes are involved in direct interspecies electron transfer to Geobacter or Methanosarcina species

Direct interspecies electron transfer(DIET)may be most important in methanogenic environments,but mechanistic studies of DIET to date have primarily focused on cocultures in which fumarate was the terminal electron acceptor.To better understand DIET with methanogens,the transcriptome of Geobacter metallireducens during DIET‐based growth with G.sulfurreducens reducing fumarate was compared with G.metallireducens grown in coculture with diverse Methanosarcina.The transcriptome of G.metallireducens cocultured with G.sulfurreducens was significantly different from those with Methanosarcina.Furthermore,the transcriptome of G.metallireducens grown with Methanosarcina barkeri,which lacks outer‐surface c‐type cytochromes,differed from those of G.metallireducens cocultured with M.acetivorans or M.subterranea,which have an outer‐surface c‐type cytochrome that serves as an electrical connect for DIET.Differences in G.metallireducens expression patterns for genes involved in extracellular electron transfer were particularly notable.Cocultures with c‐type cytochrome deletion mutant strains,ΔGmet_0930,ΔGmet_0557 andΔGmet_2896,never became established with G.sulfurreducens but adapted to grow with all three Methanosarcina.Two porin–cytochrome complexes,PccF and PccG,were important for DIET;however,PccG was more important for growth with Methanosarcina.Unlike cocultures with G.sulfurreducens and M.acetivorans,electrically conductive pili were not needed for growth with M.barkeri.Shewanella oneidensis,another electroactive microbe with abundant outer‐surface c‐type cytochromes,did not grow via DIET.The results demonstrate that the presence of outer‐surface c‐type cytochromes does not necessarily confer the capacity for DIET and emphasize the impact of the electron‐accepting partner on the physiology of the electron‐donating DIET partner.

A whole-genome association approach for large-scale interspecies traits

Dear Editor,The genetic mechanism of large-scale interspecies traits,including evolutionary novelties and the characteristics of high taxa,is a central issue in evolutionary biology.At present,genome-wide association studies(GWAS)are known as one of the most powerful and affordable tools for understanding the association between heritable variations and phenotypic changes in populations of single species.Therefore,it would be interesting to determine whether GWAS can be applied to study large-scale interspecies traits.

Blastocyst Formation and Chromosome Statuses of Reconstructed Embryos Derived from Interspecies Somatic Cell Nuclear Transfer (iSCNT)

Objective To analyze the blastocyst formation and chromosome statuses of reconstructed embryos derived from human-goat interspecies somatic cell nuclear transfer （iSCNT）, exploring the development retardant factors. Methods Human specific point probes cep2, cep6, tel2 and 13q14.2, 21q22.13 combining fluorescence in-situ hybridization （FISH） technology were used to test trophectoderm cells of blastocyst and blastomeres of development arrest nuclear transfer （NT） embryos. Results A total of 209 reconstructed embryos were recovered, and the rate of blastocyst formation was 3.8% （8/209）. FISH signals showed that chromosomal abnormalities were present in 2 blastocysts （2/8） and 146 development arrest embryos （146/201）. Conclusion The rate of blastocyst formation is low, and reconstituted embryos of development arrest showed extensive chromosome abnormalities, suggesting that a chromosomal mechanism may underlie their developmental arrest.

Influences of Nitrogen-phosphorus Ratio on the Growth and Competition of Chlorella vulga and Anabaena sp. strain PCC

This paper studied the effects of different ratios of nitrogen and phospho- rus on the growth and competition of Anabaena sp. strain PCC and chloralla vul- gads （low nitrogen-phosphorus ratio group： N/P=16：1; Medium low nitrogen-phospho- rus ratio group： N/P=32：1; Medium high nitrogen-phosphorus ratio group： N/P=64：1; High nitrogen-phosphorus ratio group： N/P=320：1）. Results suggested that the largest amount of anabaena sp.strain PCC survived in medium high nitrogen-phosphorus ratio group. The nitrogen-phosphorus ratio showed no significant influences on the growth of Chlorella vulgaris, but it exerted dramatic influences on the growth of Chlore/la vulgaris of the mixed cultivation system. The largest amount of Ch/orel/a vulgaris can be found in the medium-high nitrogen-phosphorus ratio group. The inhi- bition parameter of nitrogen-phosphorus on the algae was distinctive. Anabaena sp. strain PCC had advantages in the competition with the low nitrogen-phosphorus ra- tio and medium-low nitrogen-phosphorus ratio. Potential instability existed between anabaena sp.strain PCC and Chlorella vulgaris when the nitrogen to phosphorus ratio was medium-high and high.

Combined pretreatment using CaO and liquid fraction of digestate of rice straw: Anaerobic digestion performance and electron transfer

To improve anaerobic digestion(AD)efficiency of rice straw,solid alkaline CaO and the liquid fraction of digestate(LFD)were used as pretreatment agents of rice straw.The results showed that AD performance of rice straw with CaOLFD pretreatment was optimal in different pretreatment methods of the CaO+LFD,CaOLFD,LFD+CaO,CaO,and LFD.The maximum methane yield(314 ml(g VS)^(-1))and the highest VFAs concentration(14851 mg·L^(-1) on day 3)of the CaOLFD pretreatment group were 81%and 118%higher than that of the control group,respectively.Under the action of solid alkaline CaO,the bacteria of Clostridium,Atopostipes,Sphaerochaeta,Tissierella,Thiopseudomonas,Rikenellaceae,and Sedimentibacter could build up co-cultures with the archaeal of Methanosaeta,Methanobacterium,and Methanosarcina performing direct interspecies electron transfer(DIET)and improving AD performance of rice straw.Therefore,the combined pretreatment using CaO and LFD could not only pretreat rice straw but also stimulate co-cultures of microorganism to establish DIET enhancing AD efficiency.

Sequence analysis of the ITS region and 5.8S rDNA of Porphyra haitanensis

The sequences of the ITS(internal transcribed spacer) and 5.8S rDNA of three cultivated strains of Porphyra haitanensis thalli(NB,PT and ST) were amplified,sequenced and analyzed.In addition,the phylogenic relationships of the sequences identified in this study with those of other Porphyra retrieved from GenBank were evaluated.The results are as follows:the sequences of the ITS and 5.8S rDNA were essentially identical among the three strains.The sequences of ITS1 were 331 bp to 334 bp,while those of the 5.8S rDNA were 158 bp and the sequences of ITS2 ranged from 673 bp to 681 bp.The sequences of the ITS had a high level of homology(up to 99.5%) with that of P.haitanensis(DQ662228) retrieved from GenBank,but were only approximately 50% homologous with those of other species of Porphyra.The results obtained when a phylogenetic tree was constructed coincided with the results of the homology analysis.These results suggest that the three cultivated strains of P.haitanensis evolved conservatively and that the ITS showed evolutionary consistency.However,the sequences of the ITS and 5.8S rDNA of different Porphyra species showed great variations.Therefore,the relationship of Porphyra interspecies phyletic evolution could be judged,which provides the proof for Porphyra identification study.However,proper classifications of the subspecies and the populations of Porphyra should be determined through the use of other molecular techniques to determine the genetic variability and rational phylogenetic relationships.

In Vitro Developmental Potential of Cloned Embryos Derived from Bovine Somatic Cells and Rabbits Oocyte

reconstituted embryos were produced by nuclear transplantation using bovine ear fibroblasts at G 0 or non-G 0 stage as donor nuclei and oocytes collected from superovulated multiparous or young rabbits as recipients. After cultivation in two kinds of medium M199+10%FBS or RD+10%FBS, 112 of them developed to 2-cell stage (62.2%) and 26 to morula stage (14.4%) and 20 of them eventually developed to blastocyst stage (11.1%). There is no significant difference for the cleavage rates in two groups of reconstituted embryos derived from G 0 -stage and non-G 0 stage donor cells respectively. However, G 0-stage donor cells could result in higher rate of 8-cell16-cell stage embryos significantly (P<0.05), as well as higher rate of blastocysts (P<0.01). It seems that using two different culture systems had no significant effects on the cleavage rate, morula rate or blastocyst rate (P>0.05).

Circadian Rhythm of Root＇s Apical Meristem Mitosis Cells of Soybean

The circadian rhythms of apical meristem mitosis cells of the two types of soybean were investigated： wild soybeans - Glycine max （L.） Merr. （G. hispida Max.）, G. soja Sieb., and Zucc （G, ussuriensis Reg. and Maack）; and the hybrids of their homozygous forms （F6）. Representatives of the initial kinds and interspecific hybrids for reproduction were grown up in comparable conditions. Seeds of a soybean were grown up at 24℃ in Petri cups in thermostat in darkness during winter. For research of mitotic meristem cages activity the tips of roots were fixed temporal by acetoalcohol （fractional fixing） from 1 p.m. till 12 a.m., further up to 12 p.m. each 60 minutes. Acetokarmin was used for preparing the coloring. For researching of mitotic indexes, there have been analyzed from 6 up to 10 thousand cells at each stage （during each moment of time： 01 hour, 02, 03 06 ... 12, 13 ... 18 hours and further）. Within a day （day ＋ night） in cells of root apical meristem, three mitosis ＂waves＂ in each of the investigated forms with an absolute starting point of rest at 12 p.m., with precisely expressed further periodicity were found out. Each of the investigated forms misses in character of wave processes, on a degree of increase and recession of mitosis waves, on the level of mitotic indexes. Maximal mitotic activity at all the investigated forms is noted at 6 and 12 a.m. and 6 p.m.

“尕里巴”或“牦渣子”公牛精母细胞减数分裂及精子发生的研究

本文观察研究了黄牛与牦牛的第二代种间杂种公牛减数分裂及精子发生。Ｆ２代杂种的染色体同源性及基因的同质性比Ｆ１代杂种提高，故减数分裂和精子发生状况有所改善，但仍存在许多异常，产生的精子畸形或有缺损，因而仍是不育的。