The Plant Journal最新文献

The Korshinsk peashrub (Caragana korshinskii), known for its exceptional drought tolerance, is widely cultivated in arid and semi-arid regions for vegetation restoration and as a vital forage plant. To elucidate the genomic basis of its drought tolerance, we generated a chromosomal-scale genome sequence of C. korshinskii. Our synteny analysis disputes the previously hypothesized genus-specific whole-genome duplication event, as suggested by earlier transcriptome study of this species and its congeners. We identified that tandem duplications were critical for the expansion of gene families, such as early light-induced protein, heat shock protein 100, and Dehydrin, which are involved in cellular protection processes. These expansions are likely pivotal to the superior drought tolerance observed in C. korshinskii, as evidenced by the elevated gene expression of these genes under drought conditions. Furthermore, overexpression studies of seven tandemly duplicated DHN genes revealed a substantial enhancement in drought survival rates of seedlings, likely attributable to increased gene dosage effects. Conversely, gene silencing via virus-induced gene silencing demonstrated opposing effects. Additionally, we have established the CakorDB, a genomic resource database for C. korshinskii (https://bis.zju.edu.cn/cakordb/), accessible freely to the scientific community. Collectively, our study not only provides a valuable genomic resource for the Korshinsk peashrub but also highlights the genetic adaptations that enable C. korshinskii to thrive in desert environments, positioning its stress-responsive genes as a valuable genetic reservoir for breeding drought-resistant crops.

Abscisic acid insensitive 5 (ABI5) is a pivotal transcription factor in abscisic acid (ABA) signaling, playing an essential role in plant growth and responses to abiotic stress. This key regulator is subject to multifaceted regulation, especially on post-translational mechanisms. Recent research has shed light on the post-translational regulation of ABI5, encompassing both post-translational modifications (PTMs) and the modulation of its transcriptional activity. In this review, we provide a comprehensive overview of the current knowledge surrounding the post-translational regulation of ABI5, along with the influence of various cofactors on its transcriptional activity and protein stability. The potential biological roles of PTMs of ABI5 in the context of ABA signaling and plant stress responses are also explored. As ABI5 is one of the most extensively studied proteins in the context of plant ABA signaling and environmental stress responses, a sophisticated and precise understanding of the regulatory mechanisms that govern ABI5 is not only beneficial for its application in genetic engineering but also helpful for our exploration in the fundamental principles of post-translational regulation.

Walnut anthracnose induced by Colletotrichum gloeosporioides is a devastating disease that seriously threatens walnut cultivation. Screening novel resistance genes and exploring the molecular mechanisms are essential for disease-resistant genetic improvement of walnut. We conducted a genome-wide association studies of disease resistance traits based on the relative resistance index and single nucleotide polymorphisms (SNPs) obtained from 182 resequenced walnut accessions and 10 loci and corresponding candidate genes associated with resistance against C. gloeosporioides were identified. Then, through combined transcriptome analysis during C. gloeosporioides infection and qRT-PCR, we identified JrWDRC2A9 in SNP Chr13_36265784 loci and JrGPIAP in SNP Chr07_10106470 loci as two walnut anthracnose resistance genes. The validation of the disease resistance function of transgenic strains indicated that both JrWDRC2A9 and JrGPIAP promote walnut resistance to anthracnose. SNP Chr13_36265784 (A>G) is located in the coding region of JrWDRC2A9 causing a glutamine (JrWDRC2A9^HapI) to arginine (JrWDRC2A9^HapII). Allelic variation in the WD domain attenuates JrWDRC2A9-mediated resistance against C. gloeosporioides and the binding affinity of JrWDRC2A9 for JrTLP1. On the contrary, the allelic variation caused by SNP Chr07_10106470 (T>G) increased the walnut accessions resistance to C. gloeosporioides by promoting the expression level of JrGPIAP. Functional genomics revealed that JrGPIAP binds to the promoter of JrPR1L and activates its transcription, which is strengthened by the interaction between JrGPIAP and JrEMP24. These findings reveal the allelic variation in JrWDRC2A9 and JrGPIAP conferring resistance against C. gloeosporioides, providing a genetic basis for walnut disease resistance breeding in the future.

Glycerophosphodiester phosphodiesterases (GDPDs) enzymes are known to be involved in phospholipids degradation pathways, where glycerophosphodiesters are hydrolyzed to glycerol-3-phosphate (G3P) and corresponding alcohol. In plants, GDPDs are involved in phosphate deficiency adaptive responses and have been shown to impact root length, but the precise mechanism remains unclear. This study focuses on the rice GDPD5 gene and its role in regulating primary root growth. Our research demonstrates that OsGDPD5 encodes a functional GDPD enzyme and could hydrolyze glycerophosphocholine and glycerophosphorylethanolamine. At transcriptional levels, OsGDPD5 is preferentially expressed in the root tip and regulated by transcription factor OsPHR2. We have used CRISPR/Cas9 to generate OsGDPD5 knock-out lines, allowing us to explore its role in root growth. Our findings show that osgdpd5 mutants had a shorter primary root, which could be restored to a normal level by the exogenous application of sugar or G3P. Further, knocking out OsGDPD5 alters endogenous levels of G3P and sugars, affecting auxin biosynthesis in the root and, ultimately, primary root growth. In this manner, OsGDPD5 has a crucial role in regulating physiological processes, specifically sugar and auxin signaling, which are known to be involved in root growth regulation in rice. Our research thus unraveled a link between rice phosphate deficiency-responsive lipid remodeling and root growth via sugar-hormone signaling.

Seeds of Brassicaceae produce a large diversity of beneficial and antinutritional specialized metabolites (SMs) that influence their quality and provide resistance to stresses. While SM distribution has been described in leaves and root tissues, limited information is available about their spatiotemporal accumulation in seeds. Camelina sativa (camelina) is an oilseed Brassicaceae cultivated for human and animal nutrition and for industrial uses. While we previously explored SM diversity and plasticity, no information is available about SM distribution and expression of related proteins and genes in camelina seeds. In this study, we used a multi-omic approach, integrating untargeted metabolomics, proteomics, and transcriptomics to investigate the synthesis, modification, and degradation of SMs accumulated in camelina seed tissues (seed coat, endosperm, embryo) at six developmental and two germination stages. Metabolomic results showed distinct patterns of SMs and their related pathways, highlighting significant contrasts in seed composition and spatial distribution for the defense-related and antinutritional glucosinolate (GSL) compounds among camelina, Arabidopsis thaliana, and Brassica napus, three closely related Brassicaceae species. Notably, thanks to metabolomic and proteomic/transcriptomic techniques the variation in GSL spatial distributions was primarily driven by differences in their structure (metabolomics data) and transport (transcriptomic and proteomic data) mechanisms. Long-chain C8–C11 methylsulfinylalkyl GSLs were predominantly accumulated in the seed coat and endosperm, while mid- and short-chain C3–C7 methylsulfinylalkyl GSLs were accumulated in the embryo. Characterizing the spatial dynamics of seed SMs provides valuable insights that can guide the development of crops with optimized distribution of beneficial and toxic metabolites, improving seed nutritional profiles.

The genus Echinochloa (Poaceae) contains problematic weeds worldwide and two domesticated orphan crops. In this study, through sequencing DNA methylomes and transcriptomes, we aimed to reveal the epigenome changes and their relationship with gene expression in Echinochloa species during their polyploidization and domestication. Compared with hexaploid crop bread wheat, we found common and distinctive methylation patterns in hexaploid Echinochloa crus-galli. More diverse methylation patterns were uncovered during hexaploidization of E. crus-galli, suggesting more plasticity of the weed genome, which might contribute to its environmental adaptation. In addition, less changes in DNA methylation were observed in the two cultivated Echinochloa species, as compared with rice, indicating incomplete domestication of the Echinochloa orphan crops. Our results provide new insights into plant polyploidization and orphan crop domestication from an epigenomic perspective.

The flowering time of Arabidopsis thaliana, a model plant, is significantly accelerated when exposed to long-day (LD) conditions, as it is a typical LD plant. Consequently, the investigation of the flowering regulatory network in A. thaliana under LD conditions has garnered considerable attention in the study of flowering signals, resulting in a significant breakthrough. While many LD plants, including A. thaliana, exhibit delayed flowering under non-inductive short-day (SD) conditions, they are still capable of flowering. Nevertheless, research on the regulation of flowering induction in LD plants under non-inductive SD conditions has been limited. This study demonstrated the involvement of CYTOKININ RESPONSE FACTORS 12 (CRF12) in the regulation of flowering in A. thaliana under non-inductive conditions. Analysis of the expression patterns revealed that the activation of CRF12 expression and protein stability occurred exclusively in non-inductive environments. Molecular and genetic analyses revealed that under a non-inductive photoperiod of 12 h of light and 12 h of darkness, CRF12, CONSTANS (CO), and TARGET OF EAT 1/2 (TOE1/2) engage in competitive interactions to regulate flowering time, while in a SD photoperiod of 8 h of light and 16 h of darkness, CRF12 modulates flowering time by inhibiting the activity of TOE1/2.

Partial root-zone drying irrigation (PRD) has been widely employed to regulate crop root development and responses to environmental fluctuations. However, its role in reprogramming rhizospheric microorganisms and inducing plant stress tolerance remains largely unexplored. This study aimed to investigate the effects of PRD on the response of barley (Hordeum vulgare) plants to low temperatures under various irrigation regimes. Under low temperature, barley plants subjected to PRD exhibited a significantly enhanced net photosynthetic rate, stomatal conductance, and maximum quantum efficiency of photosystem II compared to fully irrigated plants. Additionally, these plants showed a reduction in relative conductance. These results suggest that PRD could be a viable strategy for enhancing crop stress tolerance through irrigation management. Metabolomic analysis revealed that PRD influenced the accumulation of glutathione and 9-octadecenamide in roots under low temperature, which was corroborated by transcriptome profiling data. Furthermore, the study highlighted the close association between this regulatory process and rhizosphere core microorganisms, such as Sphingobium and Mortierella, enriched in barley roots under PRD. This study revealed the mechanism underlying plant stress tolerance induction by PRD and the roles of rhizosphere microorganisms in this process. Also, the current study suggests that PRD is a promising strategy for enhancing crop stress tolerance through effective irrigation management.