5-Aminolevulinic acid(ALA)is a novel plant growth regulator that has shown outstanding capability to promote stomatal opening.Starch degradation,catalyzed byβ-amylase(EC3.2.1.2,BAM),plays an important role in stomata...5-Aminolevulinic acid(ALA)is a novel plant growth regulator that has shown outstanding capability to promote stomatal opening.Starch degradation,catalyzed byβ-amylase(EC3.2.1.2,BAM),plays an important role in stomatal opening.However,whether the starch breakdown is involved in ALA-regulating stomatal movement is unclear.In the current study,we found that exogenous ALA effectively stimulated the starch breakdown in guard cells,increasedβ-amylase activity and promoted stomatal opening in leaves of apple(Malus×domestica).Based on genome-wide identification,we identified a total of 119 members of BAM gene family in ten commonly Rosaceae crops.Analyses of gene structure,motif identification,and gene pair collinearity revealed relative conservation among members within the same group or subgroup.Among these genes,MdBAM17 and other 12 genes were identified as the orthologous genes of AtBAM1,which is responsible for starch degradation to modulate the stomatal movement in Arabidopsis.qRT-PCR analysis revealed a positive correlation between the expressions of MdBAM17 and stomatal aperture,as well asβ-amylase activity,whereas a negative correlation was observed with the starch content.Subcellular localization analysis confirmed that MdBAM17 is a chloroplast protein,consistent with the AtBAM1.MdBAM17 was mainly expressed in guard cells and responsive to exogenous ALA.Overexpressing MdBAM17 increasedβ-amylase activity and promoted starch breakdown,leading to stomatal opening,which was further strengthened by ALA.RNA-interfering MdBAM17 decreasedβ-amylase activity,resulting in starch accumulation,and impairing the stomatal opening by ALA.However,modulation of MdBAM17 expression did not affect the levels of flavonols and H_(2)O_(2)in guard cells,suggesting that MdBAM17-promoted starch degradation may function at downstream of ROS signaling in the ALAregulated stomatal opening.Our findings provide new insights into the mechanisms of ALA-regulated stomatal movement.展开更多
Erythroid cells, the predominant circulating blood cells, are essential for oxygen and carbon dioxide transport (Obeagu, 2024).Their production, erythropoiesis, involves the coordinated synthesis of globin chains and ...Erythroid cells, the predominant circulating blood cells, are essential for oxygen and carbon dioxide transport (Obeagu, 2024).Their production, erythropoiesis, involves the coordinated synthesis of globin chains and heme molecules to assemble hemoglobin(Zhang et al., 2021). The erythroid-specific enzyme δ-aminolevulinate synthase 2 (ALAS2) is a key rate-limiting factor in heme biosynthesis,with its expression increasing in late-stage erythropoiesis to meet heme demands (Sadlon et al., 1999). Zebrafish (Danio rerio) is a well-established model for studying erythropoiesis due to its genetic tractability and optical transparency (Zhang and Hamza, 2019;Zhang et al., 2021). The Tol2-mediated Gal4-UAS system has been widely applied for gene and enhancer trapping in zebrafish (Asakawa and Kawakami, 2009). However, reliable Gal4 enhancer-trap lines for erythropoiesis remain limited. Here, we report a transgenic zebrafish line with erythroid-specific Gal4FF expression under the control of the endogenous alas2 promoter, offering a more precise erythroblast labeling than the gata1a reporter line. This model provides a valuable tool for erythroid-specific investigations of blood flow dynamics and gene function.展开更多
以盆栽草莓为材料,研究了叶面喷布5-氨基乙酰丙酸(ALA)对草莓植株光合作用、叶绿素荧光特性、抗氧化酶活性和丙二醛(M DA)含量的影响.结果表明,100 m g/L ALA处理显著提高草莓叶片净光合速率(Pn),而且这一效应可能与其促进叶绿素含量和...以盆栽草莓为材料,研究了叶面喷布5-氨基乙酰丙酸(ALA)对草莓植株光合作用、叶绿素荧光特性、抗氧化酶活性和丙二醛(M DA)含量的影响.结果表明,100 m g/L ALA处理显著提高草莓叶片净光合速率(Pn),而且这一效应可能与其促进叶绿素含量和羧化效率(CE)提高,降低光呼吸速率(Rp)有关.叶绿素荧光动力学资料显示,ALA处理降低高光强(1 500μm o l.m-2.-s 1)下草莓叶片的初始荧光(Fo),表明它对光合膜系统有一定保护作用.ALA处理不仅明显提高草莓叶片最大荧光(Fm)和可变荧光(Fv),而且提高PSⅡ实际光化学效率(ΦPSⅡ)、光化学荧光猝灭(qP)、非光化学荧光猝灭系数(N PQ)、表观光合电子传递速率(ETR)、光化学速率(P CR)和天线热耗散(D),而降低了光下相对光合限制值(L(PFD)),表明叶绿素荧光产额提高和天线热耗散是保护光合器官并提高光合效率的两个方面.叶片抗氧化酶活性测定以及超氧化物歧化酶(SOD)活性抑制剂二乙基二硫代氨基甲酸(DDC)处理结果表明,ALA对草莓光合作用的促进作用还与其提高抗氧化酶活性有关.展开更多
基金supported by the Natural Science Foundation of China(Grant No.32172512)the Jiangsu Special Fund for Frontier Foundation Research of Carbon Peaking and Carbon Neutralization(Grant No.BK20220005)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘5-Aminolevulinic acid(ALA)is a novel plant growth regulator that has shown outstanding capability to promote stomatal opening.Starch degradation,catalyzed byβ-amylase(EC3.2.1.2,BAM),plays an important role in stomatal opening.However,whether the starch breakdown is involved in ALA-regulating stomatal movement is unclear.In the current study,we found that exogenous ALA effectively stimulated the starch breakdown in guard cells,increasedβ-amylase activity and promoted stomatal opening in leaves of apple(Malus×domestica).Based on genome-wide identification,we identified a total of 119 members of BAM gene family in ten commonly Rosaceae crops.Analyses of gene structure,motif identification,and gene pair collinearity revealed relative conservation among members within the same group or subgroup.Among these genes,MdBAM17 and other 12 genes were identified as the orthologous genes of AtBAM1,which is responsible for starch degradation to modulate the stomatal movement in Arabidopsis.qRT-PCR analysis revealed a positive correlation between the expressions of MdBAM17 and stomatal aperture,as well asβ-amylase activity,whereas a negative correlation was observed with the starch content.Subcellular localization analysis confirmed that MdBAM17 is a chloroplast protein,consistent with the AtBAM1.MdBAM17 was mainly expressed in guard cells and responsive to exogenous ALA.Overexpressing MdBAM17 increasedβ-amylase activity and promoted starch breakdown,leading to stomatal opening,which was further strengthened by ALA.RNA-interfering MdBAM17 decreasedβ-amylase activity,resulting in starch accumulation,and impairing the stomatal opening by ALA.However,modulation of MdBAM17 expression did not affect the levels of flavonols and H_(2)O_(2)in guard cells,suggesting that MdBAM17-promoted starch degradation may function at downstream of ROS signaling in the ALAregulated stomatal opening.Our findings provide new insights into the mechanisms of ALA-regulated stomatal movement.
基金supported by the National Key Research and Development Plan of China (2023YFA1802000)the National Natural Science Foundation of China for Distinguished Young Scholars (31925014),the National Natural Science Foundation of China Key Program (32130033),the National Natural Science Foundation of Original Exploratory Program (32350006)+5 种基金the Key Research Program of Frontier Sciences,Chinese Academy of Sciences (ZDBS-LY-SM010)Shanghai Pilot Program for Basic Research-Chinese Academy of Sciences,Shanghai Branch (JCYJ-SHFY-2022-006)Shanghai Science Technology Innovation Action Plan for Basic Research Program (21JC1406300)Haihe laboratory of Cell Ecosystem Innovation Fund (24HHXBSS00011)CAS project for Young Scientists in Basic Research (YSBR-077)supported by Science and Technology Commission of Shanghai Municipality (Shanghai Rising-Star Program,23QA1411300)
文摘Erythroid cells, the predominant circulating blood cells, are essential for oxygen and carbon dioxide transport (Obeagu, 2024).Their production, erythropoiesis, involves the coordinated synthesis of globin chains and heme molecules to assemble hemoglobin(Zhang et al., 2021). The erythroid-specific enzyme δ-aminolevulinate synthase 2 (ALAS2) is a key rate-limiting factor in heme biosynthesis,with its expression increasing in late-stage erythropoiesis to meet heme demands (Sadlon et al., 1999). Zebrafish (Danio rerio) is a well-established model for studying erythropoiesis due to its genetic tractability and optical transparency (Zhang and Hamza, 2019;Zhang et al., 2021). The Tol2-mediated Gal4-UAS system has been widely applied for gene and enhancer trapping in zebrafish (Asakawa and Kawakami, 2009). However, reliable Gal4 enhancer-trap lines for erythropoiesis remain limited. Here, we report a transgenic zebrafish line with erythroid-specific Gal4FF expression under the control of the endogenous alas2 promoter, offering a more precise erythroblast labeling than the gata1a reporter line. This model provides a valuable tool for erythroid-specific investigations of blood flow dynamics and gene function.
