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Chromosome painting is a powerful technique for chromosome and genome studies. We developed a flexible chromosome painting technique based on multiplex PCR of a synthetic oligonucleotide (oligo) library in cucumber (Cucumis sativus L., 2n = 14). Each oligo in the library was associated with a universal as well as nested specific primers for amplification, which allow the generation of different probes from the same oligo library. We were also able to generate double‐stranded labelled oligos, which produced much stronger signals than single‐stranded labelled oligos, by amplification using fluorophore‐conjugated primer pairs. Oligos covering cucumber chromosome 1 (Chr1) and chromosome 4 (Chr4) consisting of eight segments were synthesized in one library. Different oligo probes generated from the library painted the corresponding chromosomes/segments unambiguously, especially on pachytene chromosomes. This technique was then applied to study the homoeologous relationships among cucumber, C. hystrix and C. melo chromosomes based on cross‐species chromosome painting using Chr4 probes. We demonstrated that the probe was feasible to detect interspecies chromosome homoeologous relationships and chromosomal rearrangement events. Based on its advantages and great convenience, we anticipate that this flexible oligo‐painting technique has great potential for the studies of the structure, organization, and evolution of chromosomes in any species with a sequenced genome.  相似文献   
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阴道微生态是由阴道的局部解剖结构、周期性的内分泌变化、阴道局部免疫系统和阴道内微生物菌群共同组成的阴道环境和生态系统。多项研究证实阴道微生态失调通过局部炎症因子释放、黏膜免疫应答的改变和局部代谢变化,可引起早产的发生。阴道内小分子物质如糖类、短链脂肪酸和胺类通过代谢路径和代谢产物在阴道微生态失调与早产的发病机制起作用。近年来,阴道微生态的理念得到重视,治疗方法由传统的抗生素治疗转向了综合治疗,目的是恢复正常阴道菌群和阴道上皮黏膜免疫系统。但阴道微生态与宿主之间存在复杂的相互作用,因此仍需要进一步的研究。  相似文献   
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利用叶绿素荧光技术,对强光胁迫下以及叶黄素循环抑制剂-二硫苏糖醇(DTT)和D1蛋白合成抑制剂-硫酸链霉素(SM)处理后毛竹(Phyllostachys edulis (Carr.) Lehaie)的光抑制特征进行研究。结果显示:在夏季中午强光或人为强光胁迫下,毛竹叶片最大光化学效率Fv/Fm均显著降低;在下午光强减弱或黑暗、弱光条件下,Fv/Fm可有效恢复。DTT和SM均可抑制毛竹叶片非光化学淬灭(NPQ),且DTT效果明显优于SM。另外,在强光下,DTT和SM处理均能使毛竹叶片Fv/Fm、实际光化学效率Y(Ⅱ)和光化学淬灭qP等荧光参数下降幅度增大。研究结果表明毛竹叶片具有完善的光破坏防御机制,NPQ与叶黄素循环和D1蛋白周转紧密关联,在叶片光保护机制中具有重要作用。  相似文献   
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温度变化和钾添加对扁秆藨草生长及繁殖的影响 人类活动导致的气候变暖和农业面源污染已被认为是影响湿地植物生长和繁殖的重要因素。为了预 测和缓解这些人类活动的影响,研究沼泽植物如何响应这些环境变化具有重要意义。本研究选取在欧亚 大陆广泛分布的莎草科球茎植物扁秆藨草(Bolboschoenus planiculmis)为研究对象,考察气温变化(恒温: 15、20、25 °C及交替温度:20/10和30/15 °C)和钾添加(0、1、3、9 和18 mmol/L)对其生长和繁殖性状 的影响。研究结果表明,高的恒温(20、25 °C)比高的交替温度(30/15 °C)更有利于扁秆藨草球茎的形成, 而地上生物量和株高一般在较高温度下(30/15、25 °C)达到最大值。扁秆藨草的繁殖和生长性状均与施钾量 呈驼峰型关系,最适施钾量在1–3 mmol/L K。高恒温效应和最适钾浓度的交互作用对繁殖性状的促进作 用最大,但是,较高的温度(30/15和25 °C)和0–9 mmol/L的钾浓度只促进了生长性状的生长。综上所述, 扁秆藨草的种群优势度可能受益于全球变暖和额外的钾添加。  相似文献   
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Dear Editor, The rapid emergence and persistence of the pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has had enormous impacts on global health and the economy.Effective vaccines against SARS-CoV-2 are urgently needed to control the coronavirus disease 2019(COVID-19) pandemic,and multiple vaccines have been found to be efficacious in preventing symptomatic COVID-19(Polack et al.,2020;Wu et al.,2020;Jones and Roy,2021).We have developed a traditional beta-propiolactone-inacti-vated aluminum hydroxide-adjuvanted whole-virion SARS-CoV-2 vaccine (BBIBP-CorV),which elicited protective immune responses in clinical trials (Wang et al.,2020;Xia et al.,2021).The vaccine has been granted conditional approvals or emergency use authorizations (EUAs) in China and other countries.  相似文献   
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Liu  Yangqiu  Wang  Yu  Lou  Yaxin  Tian  Weiping  Que  Kehua 《Journal of molecular histology》2021,52(5):1105-1114

TRPA1 and TRPV1 channels respond to external stimulation as pain mediators and form a complex with a transmembrane protein TMEM100 in some tissues. However, their expression and interaction in dental pulp is unclear. To investigate the functional co-expression of TRPA1 channel, TRPV1 channel and TMEM100 in human odontoblasts (HODs), immunohistochemistry, immunofluorescence staining and Western blot were used to study their co-localization and expression in both native HODs and cultured HOD-like cells. Calcium imaging was used to detect the functional interaction between TRPA1 and TRPV1 channels. Immunohistochemistry and multiple immunofluorescence staining of tooth slices showed positive expression of TRPA1 channel, TRPV1 channel and TMEM100 mainly in the cell bodies of HODs, and TRPA1 channel presented more obvious immunofluorescence in the cell processes than TRPV1 channel and TMEM100. HALO software analysis showed that TRPA1 and TRPV1 channels were positively expressed in most TMEM100+ HODs and these three proteins were strongly correlated in HODs (P < 0.01). The protein expression levels of TRPA1 channel, TRPV1 channel and TMEM100 in HODs showed no significant difference (P?>?0.05). Double immunofluorescence staining of cultured HOD-like cells visually demonstrated that TRPA1 and TRPV1 channel were both highly co-localized with TMEM100 with similar expressive intensity. Calcium imaging showed that there was a functional interaction between TRPA1 and TRPV1 channels in HOD-like cells, and TRPA1 channel might play a greater role in this interaction. Overall, we concluded that TRPA1 channel, TRPV1 channel and TMEM100 could be functionally co-expressed in HODs.

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