In northern China,light and temperature are major limiting factors for plant growth,particularly during seed production and seedling establishment.While previous studies suggested a possible role for the MYB97 gene in...In northern China,light and temperature are major limiting factors for plant growth,particularly during seed production and seedling establishment.While previous studies suggested a possible role for the MYB97 gene in cold-stress,confirmation through documented evidence was lacking.In this study,we transformed the MYB97 gene from Iris laevigata into tobacco,and discovered that the gene boosted photosynthesis,photoprotection and resilience to cold.The transgenic tobacco seeds exhibited enhanced germination and accelerated seedling growth.Moreover,these plants had decreased levels of MDA(Malondialdehyde)and relative conductance,coupled with elevated concentrations of proline and soluble sugars.This response was accompanied by heightened activity of antioxidant enzymes during periods of cold stress(4 and−2℃).Exposure to low temperatures(0–15℃)also reduced heights but accentuated primary root growth in transgenic tobacco plants.Additionally,tobacco leaves showed an increased growth along with higher chlorophyll levels,net photosynthetic rates,stomatal conductance,transpiration rates and non-photochemical quenching coefficient.This study shows that IlMYB97(The MYB97 genes in I.laevigata)improves cold-resistance,and enhances photosynthesis and photoprotective ability,and thus overall growth and development.These findings would offer the genetic resources to further study cold resistance and photosynthesis.展开更多
Acceleration of tooth movement during orthodontic treatment is challenging, with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step. Recent studies have demonstrated that mechanor...Acceleration of tooth movement during orthodontic treatment is challenging, with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step. Recent studies have demonstrated that mechanoreceptors on the surface of monocytes/macrophages, especially adhesion G protein-coupled receptors (aGPCRs), play important roles in force sensing.However, its role in the regulation of osteoclast differentiation remains unclear. Herein, through single-cell analysis, we revealed that CD97, a novel mechanosensitive aGPCR, was expressed in macrophages. Compression upregulated CD97 expression and inhibited osteoclast differentiation;while knockdown of CD97 partially rescued osteoclast differentiation. It suggests that CD97 may be an important mechanosensitive receptor during osteoclast differentiation. RNA sequencing analysis showed that the Rap1a/ERK signalling pathway mediates the effects of CD97 on osteoclast differentiation under compression. Consistently, we clarified that administration of the Rap1a inhibitor GGTI298 increased osteoclast activity, thereby accelerating tooth movement. In conclusion,our results indicate that CD97 suppresses osteoclast differentiation through the Rap1a/ERK signalling pathway under orthodontic compressive force.展开更多
采用夹杂物含量水平不同的两批次粉末,通过相同的热等静压制度制备了FGH97合金,研究了夹杂物对FGH97合金力学性能的影响。对比测试了两组粉末制备FGH97合金的拉伸性能,表征了粉末特征、合金组织、拉伸断口。结果表明,采用真空惰性气体雾...采用夹杂物含量水平不同的两批次粉末,通过相同的热等静压制度制备了FGH97合金,研究了夹杂物对FGH97合金力学性能的影响。对比测试了两组粉末制备FGH97合金的拉伸性能,表征了粉末特征、合金组织、拉伸断口。结果表明,采用真空惰性气体雾化(Vacuum induction melting gas atomization,VIGA)法制备的粉末,细粉收集率高,制备的合金晶粒细小,容易引入夹杂物。富Si的异常颗粒夹杂会使合金中产生贫γ′区,影响粉末间的结合,降低FGH97合金的塑性。热等静压态的FGH97合金室温延伸率为9.5%,650℃的延伸率为1%。FGH97合金经过固溶+时效热处理后,基体中的贫γ′区消失,FGH97合金的塑性得到显著提升,FGH97合金室温延伸率提升至14.25%,650℃的延伸率提升至6%。展开更多
基金supported by the Science and Technology Basic Resources Investigation Program of China(2019FY100500)the Fun-damental Research Funds for the Central Universities(2572023CT18)the Natural Fund Project of Heilongjiang Province(LH 2020C 044).
文摘In northern China,light and temperature are major limiting factors for plant growth,particularly during seed production and seedling establishment.While previous studies suggested a possible role for the MYB97 gene in cold-stress,confirmation through documented evidence was lacking.In this study,we transformed the MYB97 gene from Iris laevigata into tobacco,and discovered that the gene boosted photosynthesis,photoprotection and resilience to cold.The transgenic tobacco seeds exhibited enhanced germination and accelerated seedling growth.Moreover,these plants had decreased levels of MDA(Malondialdehyde)and relative conductance,coupled with elevated concentrations of proline and soluble sugars.This response was accompanied by heightened activity of antioxidant enzymes during periods of cold stress(4 and−2℃).Exposure to low temperatures(0–15℃)also reduced heights but accentuated primary root growth in transgenic tobacco plants.Additionally,tobacco leaves showed an increased growth along with higher chlorophyll levels,net photosynthetic rates,stomatal conductance,transpiration rates and non-photochemical quenching coefficient.This study shows that IlMYB97(The MYB97 genes in I.laevigata)improves cold-resistance,and enhances photosynthesis and photoprotective ability,and thus overall growth and development.These findings would offer the genetic resources to further study cold resistance and photosynthesis.
基金supported by the Natural Science Foundation of Hebei Province (H2020206226)Hebei Province Science and Technology Support Program (18277756D)+1 种基金the Science and Technology Research Project of Hebei Higher Education Institutions (ZD2022010)High-level Talent Funding Project of Hebei (C20231141) to W.W。
文摘Acceleration of tooth movement during orthodontic treatment is challenging, with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step. Recent studies have demonstrated that mechanoreceptors on the surface of monocytes/macrophages, especially adhesion G protein-coupled receptors (aGPCRs), play important roles in force sensing.However, its role in the regulation of osteoclast differentiation remains unclear. Herein, through single-cell analysis, we revealed that CD97, a novel mechanosensitive aGPCR, was expressed in macrophages. Compression upregulated CD97 expression and inhibited osteoclast differentiation;while knockdown of CD97 partially rescued osteoclast differentiation. It suggests that CD97 may be an important mechanosensitive receptor during osteoclast differentiation. RNA sequencing analysis showed that the Rap1a/ERK signalling pathway mediates the effects of CD97 on osteoclast differentiation under compression. Consistently, we clarified that administration of the Rap1a inhibitor GGTI298 increased osteoclast activity, thereby accelerating tooth movement. In conclusion,our results indicate that CD97 suppresses osteoclast differentiation through the Rap1a/ERK signalling pathway under orthodontic compressive force.
文摘采用夹杂物含量水平不同的两批次粉末,通过相同的热等静压制度制备了FGH97合金,研究了夹杂物对FGH97合金力学性能的影响。对比测试了两组粉末制备FGH97合金的拉伸性能,表征了粉末特征、合金组织、拉伸断口。结果表明,采用真空惰性气体雾化(Vacuum induction melting gas atomization,VIGA)法制备的粉末,细粉收集率高,制备的合金晶粒细小,容易引入夹杂物。富Si的异常颗粒夹杂会使合金中产生贫γ′区,影响粉末间的结合,降低FGH97合金的塑性。热等静压态的FGH97合金室温延伸率为9.5%,650℃的延伸率为1%。FGH97合金经过固溶+时效热处理后,基体中的贫γ′区消失,FGH97合金的塑性得到显著提升,FGH97合金室温延伸率提升至14.25%,650℃的延伸率提升至6%。
