Reactive oxygen species:Multidimensional regulators of plant adaptation to abiotic stress and development

Reactive oxygen species(ROS)are produced as undesirable by-products of metabolism in various cellular compartments,especially in response to unfavorable environmental conditions,throughout the life cycle of plants.Stressinduced ROS production disrupts normal cellular function and leads to oxidative damage.To cope with excessive ROS,plants are equipped with a sophisticated antioxidative defense system consisting of enzymatic and non-enzymatic components that scavenge ROS or inhibit their harmful effects on biomolecules.Nonetheless,when maintained at relatively low levels,ROS act as signaling molecules that regulate plant growth,development,and adaptation to adverse conditions.Here,we provide an overview of current approaches for detecting ROS.We also discuss recent advances in understanding ROS signaling,ROS metabolism,and the roles of ROS in plant growth and responses to various abiotic stresses.

Chromatin-associated SUMOylation controls the transcriptional switch between plant development and heat stress responses

The post-translational protein modification known as SUMOylation has conserved roles in the heat stress responses of various species.The functional connection between the global regulation of gene expression and chromatin-associatedSUMOylation in plant cells isunknown.Here,weuncovereda genome-wide relationship between chromatin-associated SUMOylation and transcriptional switches in Arabidopsis thaliana grown at room temperature,exposed to heat stress,and exposed to heat stress followed by recovery.The small ubiquitin-like modifier(SUMO)-associated chromatin sites,characterized by whole-genome ChIP-seq,were generally associated with active chromatin markers.In response to heat stress,chromatin-associated SUMO signals increased at promoter-transcriptional start site regions and decreased in gene bodies.RNAseq analysis supported the role of chromatin-associatedSUMOylation in transcriptional activation during rapid responses to high temperature.Changes inSUMOsignals on chromatinwere associated with the upregulation of heat-responsivegenesandthedownregulation ofgrowth-relatedgenes.Disruption of theSUMOligasegene SIZ1 abolished SUMOsignals on chromatin and attenuated rapid transcriptional responses to heat stress.The SUMO signal peaks were enriched in DNA elements recognized by distinct groups of transcription factors under different temperature conditions.These observations provide evidence that chromatin-associated SUMOylation regulates the transcriptional switch between development and heat stress response in plant cells.

The cytochrome P450 superfamily: Key players in plant development and defense

The cytochrome P450 （CYP） superfamily is the largest enzymatic protein family in plants, and it also widely exists in mammals, fungi, bacteria, insects and so on. Members of this superfamily are involved in multiple metabolic pathways with distinct and complex functions, playing important roles in a vast array of reactions. As a result, numerous secondary metabolites are synthesized that function as growth and developmental signals or protect plants from various biotic and abiotic stresses. Here, we summarize the characterization of CYPs, as well as their phylogenetic classification. We also focus on recent advances in elucidating the roles of CYPs in mediating plant growth and development as well as biotic and abiotic stresses responses, providing insights into their potential utilization in plant breeding.

Advances in structure and function of auxin response factor in plants

Auxin is a crucial phytohormone that has various effects on the regulators of plant growth and development.Auxin signal transduction is mainly controlled by two gene families:auxin response factor(ARF)and auxin/indole-3-acetic acid(Aux/IAA).ARFs are plant-specific transcription factors that bind directly to auxin response elements in the promoters of auxinresponsive genes.ARF proteins contain three conserved regions:a conserved N-terminal B3DNA-binding domain,a variable intermediate middle region domain that functions in activation or repression,and a C-terminal domain including the Phox and Bem1p region for dimerization,similar to theⅢandⅣelements of Aux/IAA,which facilitate protein–protein interaction through homodimerization of ARF proteins or heterodimerization of ARF and Aux/IAA proteins.In the two decades following the identification of the first ARF,23 ARF members have been identified and characterized in Arabidopsis.Using whole-genome sequencing,22,25,23,25,and 36 ARF genes have been identified in tomato,rice,wheat,sorghum,and maize,respectively,in addition to which the related biofunctions of some ARFs have been reported.ARFs play crucial roles in regulating the growth and development of roots,leaves,flowers,fruits,seeds,responses to biotic and abiotic stresses,and phytohormone signal crosstalk.In this review,we summarize the research progress on the structures and functions of ARFs in Arabidopsis,tomato,and cereal crops,to provide clues for future basic research on phytohormone signaling and the molecular design breeding of crops.

Active DNA demethylation in plants:20 years of discovery and beyond

Maintaining proper DNA methylation levels in the genome requires active demethylation of DNA.However,removing the methyl group from a modified cytosine is chemically difficult and therefore,the underlying mechanism of demethylation had remained unclear for many years.The discovery of the first eukaryotic DNA demethylase,Arabidopsis thaliana REPRESSOR OF SILENCING 1(ROS1),led to elucidation of the 5-methylcytosine base excision repair mechanism of active DNA demethylation.In the 20 years since ROS1 was discovered,our understanding of this active DNA demethylation pathway,as well as its regulation and biological functions in plants,has greatly expanded.These exciting developments have laid the groundwork for further dissecting the regulatory mechanisms of active DNA demethylation,with potential applications in epigenome editing to facilitate crop breeding and gene therapy.

Major episodes of horizontal gene transfer drove the evolution of land plants

How horizontal gene transfer(HGT)has contributed to the evolution of animals and plants remains a major puzzle.Despite recent progress,defining the overall scale and pattern of HGT events in land plants has been largely elusive.In this study,we performed systematic analyses for acquired genes in different plant groups and throughout land plant evolution.We found that relatively recent HGT events occurred in char-ophytes and all major land plant groups,but their frequency declined rapidly in seed plants.Two major ep-isodes of HGT events occurred in land plant evolution,corresponding to the early evolution of strepto-phytes and the origin of land plants,respectively.Importantly,a vast majority of the genes acquired in the two episodes have been retained in descendant groups,affecting numerous activities and processes of land plants.We analyzed some of the acquired genes involved in stress responses,ion and metabolite transport,growth and development,and specialized metabolism,and further assessed the cumulative ef-fects of HGT in land plants.

Mitogen-activated protein kinase cascades in plant signaling

Mitogen-activated protein kinase(MAPK)cascades are key signaling modules downstream of receptors/sensors that perceive either endogenously produced stimuli such as peptide ligands and damage-associated molecular patterns(DAMPs)or exogenously originated stimuli such as pathogen/microbe-associated molecular patterns(P/MAMPs),pathogen-derived effectors,and environmental factors.In this review,we provide a historic view of plant MAPK research and summarize recent advances in the establishment of MAPK cascades as essential components in plant immunity,response to environmental stresses,and normal growth and development.Each tier of the MAPK cascades is encoded by a small gene family,and multi ple members can function redundantly in an MAPK cascade.Yet,they carry out a diverse array of biological functions in plants.How the signaling specificity is achieved has become an interesting topic of MAPK research.Future investigations into the molecular mechanism(s)underlying the regulation of MAPK activation including the activation kinetics and magnitude in response to a stimulus,the spatiotemporal expression patterns of all the components in the signaling pathway,and functional characterization of novel MAPK substrates are central to our understanding of MAPK functions and signaling specificity in plants.

观赏植物NAC转录因子的研究进展

NAC转录因子家族在调节植物的生长发育中发挥着重要的作用,在模式植物、作物中已进行了大量研究,但是在观赏植物中的研究还缺乏系统性的梳理和探讨。本综述介绍了NAC转录因子的结构和分类,并梳理了2004-2023年NAC转录因子在观赏植物器官生长发育和胁迫响应上的生物学功能研究,其中观赏植物器官生长发育主要集中在叶缘形态建成、花器官发育、叶片衰老、花瓣衰老、种球休眠5个方面,胁迫响应则集中在干旱、盐、碱、冷、热等非生物胁迫,在生物胁迫中报道较少。最后,鉴于观赏植物NAC转录因子大部分都还停留在生物信息学分析以及表达模式分析等功能初探阶段,本文在结合观赏植物全基因组测序继续开展NAC转录因子鉴定研究、挖掘观赏植物中与模式植物存在不同作用机制的NAC转录因子、解析观赏植物NAC转录因子与其他转录因子间的调控网络、加快利用推进基因工程或编辑技术开展观赏植物的分子育种工作等4个方面,对未来NAC转录因子在观赏植物中的研究提出了展望。

植物14⁃3⁃3蛋白结构与功能的研究进展

14⁃3⁃3蛋白是一类进化上高度保守的磷酸化识别蛋白,以同源或异源二聚体的形式发挥功能。植物14⁃3⁃3蛋白不但参与调控植物开花、叶绿体发育和移动、气孔开放、种子发育、细胞伸长和分裂等过程,还参与调控植物对环境胁迫的响应,如干旱、盐碱和温度等胁迫响应。目前,已鉴定与植物14⁃3⁃3蛋白互作的蛋白超过300个,说明14⁃3⁃3蛋白在植物生长发育过程中具有重要作用。本文主要总结了近年来植物14⁃3⁃3蛋白的结构及功能方面的研究进展。

谷氨酸受体蛋白调控植物生长与胁迫应答的研究进展

植物谷氨酸受体(glutamate receptor-like,GLRs)是动物离子型谷氨酸受体(inotropic glutamate receptors,iGluRs)的同源蛋白,在开花植物中具有多个拷贝,常以功能冗余的基因家族形式共同调节植物生长发育和逆境应答过程。GLRs在植物中发挥作用的机制与其动物同源蛋白既有类似之处,但又表现出植物特异性。iGluRs在哺乳动物的神经系统中发挥重要作用。在iGluRs介导的神经传导中,由突触前膜释放的神经递质识别并结合突触后膜的iGluRs,iGluRs介导的阳离子内流引起突触后膜的去极化,形成动作电位的传递,构成神经传导的基础。过去20多年的研究发现,植物GLRs也可以作为离子通道蛋白,通过调节跨膜离子流行使功能。本文系统综述了植物谷氨酸受体的蛋白结构和演化特征,并对已报道的重要功能位点进行阐释;总结了近些年来对植物谷氨酸受体蛋白在植物生长发育不同时期,以及多种生物和非生物逆境应答中的功能的研究进展,并比较了其与动物iGluRs作用机制的异同;提出并梳理了该领域仍待解决的重要科学问题;最后展望了该蛋白家族在作物耐逆育种中的重要应用前景和价值,以期为改良作物耐逆性状提供线索。

Advances in proteome-wide analysis of plant lysine acetylation

Lysine acetylation(LysAc)is a conserved and important post-translational modification(PTM)that plays a key role in plant physiological and metabolic processes.Based on advances in Lys-acetylated protein immunoenrichment and mass-spectrometric technology,LysAc proteomics studies have been performed in many species.Such studies have made substantial contributions to our understanding of plant LysAc,revealing that Lys-acetylated histones and nonhistones are involved in a broad spectrum of plant cellular processes.Here,we present an extensive overview of recent research on plant Lys-acetylproteomes.We provide in-depth insights into the characteristics of plant LysAc modifications and the mechanisms by which LysAc participates in cellular processes and regulates metabolism and physiology during plant growth and development.First,we summarize the characteristics of LysAc,including the properties of Lys-acetylated sites,the motifs that flank Lys-acetylated lysines,and the dynamic alterations in LysAc among different tissues and developmental stages.We also outline a map of Lys-acetylated proteins in the Calvin–Benson cycle and central carbon metabolism–related pathways.We then introduce some examples of the regulation of plant growth,development,and biotic and abiotic stress responses by LysAc.We discuss the interaction between LysAc and Na-terminal acetylation and the crosstalk between LysAc and other PTMs,including phosphorylation and succinylation.Finally,we propose recommendations for future studies in the field.We conclude that LysAc of proteins plays an important role in the regulation of the plant life cycle.

Versatile Piriformospora indica and Its Potential Applications in Horticultural Crops

Modern horticultural crop production systems target the exploitation of sustainable techniques for crop improvement while maintaining balance with the environment. Several beneficial microbes have been investigated and have yielded remarkable results. The endophytic fungus, Piriformospora indica, is one microbe group with the potential to offer numerous benefits and opportunities in modern horticultural crop production. This plant growth-promoting mycorrhizal fungus is of particular interest due to its beneficial implications in plant growth and development. The fungus has been experimentally proven to significantly improve water and nutrient/mineral absorption, early flowering, seed production/germination and plant photosynthetic capability, growth rates;especially in nutrient-deprived soils, alter the production of secondary metabolites, and promote adaptation, tolerance and/or resistance to biotic and abiotic stressors. Its unique capability to be axenically cultured makes it feasible for research and application. These attributes in combinations with its broad host range, offer immense potential for this fungus for research in horticultural plant improvement. Thus, this review highlights the potential applications of P. indica in horticultural crops research and production.

高温胁迫对水稻生长发育的伤害效应及其防御对策

全球气候变暖背景下,高温天气频发,高温热害已成为严重影响水稻高产稳产的主要问题之一。文章概述了高温胁迫对水稻生长发育、颖花育性、活性氧积累与膜损伤、光合作用、内源植物激素、产量和品质等的影响,提出水稻高温热害的防御对策,包括选育耐高温品种、合理调整播期、加强稻田水肥管理、合理施用植物生长调节剂等,并对今后水稻高温热害的研究方向作了展望,以期为开展水稻抗热栽培和耐高温水稻品种的选育提供参考。

AMF对观赏植物生长发育影响的研究进展

从植物营养转运、表观形态、光合作用以及非生物胁迫抗性4个方面总结丛枝菌根真菌(AMF)对观赏植物生长发育的影响。分析表明,AMF通过调控营养转运基因的表达和提高观赏植物吸收养分的面积促进观赏植物体内营养元素的积累,改善植物营养吸收;通过提高植物体内叶绿素含量、光合酶活性等提高植物的碳固定能力和改善源-库关系,进而增强植物光合作用效率;通过调控渗透调节物质、抗氧化等酶活性提高植物的抗旱、耐盐碱及高温等抗逆性。今后应进一步研究AMF参与钾离子、叶绿素荧光参数以及胁迫相关转录因子(如GRAS家族、AP2/ERF家族、MYB家族)的调控机制,以探究AMF的共生机制。

园艺植物WRKY基因功能研究进展

WRKY转录因子是植物中特有的一类反式作用因子。WRKY基因家族成员众多,是植物中最大的转录因子家族之一。目前,已在多种园艺植物中对该家族进行了全基因组鉴定。大量研究表明,WRKY转录因子参与了植物中多种生物学过程,如营养剥夺、胚胎发生、种子发育、毛状体发育、叶片衰老及其他发育和激素调节的过程,是许多调控信号网络的重要组成部分。WRKY转录因子还可参与植物适应各种逆境的转录调控,已被证明其在生物应激反应中发挥重要作用并参与植物的防御机制,其在植物防御病菌、病毒和虫害调控过程中的重要作用正被逐步揭示。此外,WRKY转录因子在植物响应环境中非生物胁迫方面的作用也被不断解析,其可参与调控植物对干旱、温度、盐及渗透的响应,并在此过程中发挥正向或负向调节作用。本文基于近年来的相关研究成果,重点综述了WRKY转录因子在园艺植物生长发育、胁迫响应和代谢合成方面所发挥的作用和调控机理,进一步明确园艺植物WRKY转录因子的重要生物学功能,阐明WRKY转录因子介导的转录调控网络,为园艺植物优良性状相关的遗传资源挖掘和分子育种提供理论支撑。

茉莉酸调控植物生长发育和胁迫的研究进展

植物作为不可移动的生物,感知外界刺激通过改变自身信号转导对其做出反应。植物激素作为重要的信号分子,在植物应对不同生物和非生物胁迫反应中发挥作用,以调节植物生长发育并适应不断变化的环境。茉莉酸是植物体内的重要激素之一,目前它的合成途径、生理作用等已有大量研究,但对其感知环境变化并做出反应的信号转导途径以及与其他植物激素的相互作用方面的研究还有空白之处。本文主要阐述茉莉酸在调控植物生长发育、胁迫应答及其与其他植物激素的相互作用方面的研究进展。

植物褪黑素功能及其作用机制的研究进展

褪黑素是一种重要的植物生长调节剂,在植物中具有多种功效。鉴于褪黑素在植物中的多种功能作用,为了给褪黑素在农业生产中的应用提供理论依据,通过查阅并梳理相关文献,阐述了植物中褪黑素的合成及代谢途径,褪黑素对植物生长发育的调控及对植物响应逆境胁迫的影响和褪黑素诱导作用的机制。褪黑素不仅参与植物种子萌发、根系发育、开花结果等生长发育过程,还能充当胁迫缓解剂,调节植物对多种生物胁迫/非生物胁迫的响应,且用外源褪黑素处理能够有效地缓解低温、干旱、盐碱以及病虫害等对植物的损伤程度,今后的研究应将盆栽试验与田间试验结合起来,以加速褪黑素在农业中的广泛应用。

植物bHLH基因家族研究进展及在药用植物中的应用前景

碱性/螺旋-环-螺旋(bHLH)转录因子是植物中第二大转录因子家族,该家族广泛存在于各种植物的基因组中,并在植物生长发育、次生代谢、非生物逆境胁迫响应等方面发挥着重要的调控作用。本文全面综述了植物bHLH基因家族成员的结构特征、分类规则及其生物学功能的研究进展,重点梳理总结了bHLH在植物生长发育和非生物胁迫(干旱、低温、盐、重金属)中的应答和调控,以及在次生代谢产物生物合成及动态积累过程中的重要作用,可为深入研究bHLH在生长发育、植物抗逆及品质形成等方面的分子调控机制及种质资源的开发提供指导。同时,因bHLH广泛参与调控植物次生代谢产物的合成和积累,已成为分子生药学和中药生态农业研究的热点。为此,本文进一步总结了近年来研究较为透彻的两种药用植物(丹参Salvia miltiorrhiza、黄花蒿Artemisia annua)中bHLH基因家族及其成员的研究进展,以期为药用植物bHLH基因家族的深入研究提供参考,并为药用植物的分子育种、拟境栽培等工作的开展以及中药生态农业的发展提供新思路。

DNA甲基化调控园艺植物生长发育及非生物胁迫应答研究进展

DNA甲基化作为表观遗传调控的重要机制之一,通常发生在植物胞嘧啶碱基中,包含CG、CHG、CHH三种类型。主要影响染色质结构和基因的转录效率,在植物细胞基因表达调控、基因组稳定性维持等方面起重要作用。非生物胁迫影响植物的生长发育和繁殖最终导致植物死亡。基于已有研究发现,DNA甲基化可诱导非生物胁迫下植物的表型改变。DNA甲基化水平在植物非生物胁迫生长过程存在的变化机制受到甲基化酶和去甲基化酶的影响。甲基化状态上调(启动)或下调(关闭)基因表达以确保自身适应生长及发育,从而使植物在一定程度上适应和抵抗逆境伤害。这些信号转导通路可以引起植物形态、生理和生化的改变以适应逆境。本文对DNA甲基化功能及其在园艺植物的生长发育与非生物胁迫响应方面的研究进行了分析与总结,探讨了DNA甲基化在园艺植物表观遗传研究中存在的问题及展望,为园艺植物遗传改良及抗逆分子机理研究提供参考。

重金属复合污染对植物的影响研究进展

土壤复合污染情况普遍,在复合污染条件下,土壤中各重金属之间存在加和、拮抗、协同作用,使得其较单一污染更加复杂,对植物生长的影响也存在差异性。本文综述了重金属复合污染对植物生长发育、超微结构、生理生化特征的影响,复合污染条件下植物对重金属的吸收转运机制,以及复合污染对植物根际微生物的影响,对明确重金属对植物生长的影响机理、提高植物对重金属的适应性具有重要的参考意义,并为重金属复合污染土壤植物的栽培及育种奠定理论基础。