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Jiayang Li

Publications and source records attributed to Jiayang Li.

14 recordsLinked to original sources
PubMed2026

Strigolactones constrain rice drought acclimation by suppressing ROS scavenging through the D53-OsWRKY31-ZFP36 module.

Strigolactones (SLs) are a class of plant hormones essential for tiller development and yield under diverse environmental conditions. Drought is a major limiting factor for rice yields. Although SLs contribute to drought resistance, mechanisms and practical applications of SL pathway in drought acclimation of rice remain poorly understood. Our study shows that short-term dehydration represses SL biosynthesis in rice roots. Genetic assays indicate that disruption of SL biosynthesis or signaling elevates rice drought resistance, whereas SL signaling activation or supplementation with the SL analog GR244DO impairs drought resistance. SLs negatively regulate drought acclimation by promoting degradation of the repressor protein DWARF53 (D53). D53 interacts with the transcription factor OsWRKY31 via its N-terminal domain and suppresses the protein level of OsWRKY31, which binds to and represses transcription of the ZFP36 promoter. ZFP36 encodes a zinc-finger transcription factor that promotes H2O2 scavenging to sustain reactive oxygen species (ROS) homeostasis during drought stress. Notably, the drought-resistant upland rice variety IRAT109 exhibits lower SL levels in root exudates than the lowland rice variety Nipponbare (NP). Genome editing of key components in SL pathway enhances drought resistance in NP, Huazhan (HZ), and IRAT109. The agronomic potential of tuning SL biosynthesis is further supported by the elite D17/HTD1 allele, which weakens SL biosynthesis and improves drought resistance and grain yield in Nekken 2 (NK2) under field conditions. These findings uncover a key mechanism underlying SL-repressed drought acclimation in rice and provide an effective strategy to improve drought resistance in diverse rice varieties amid ongoing climate change.

D53↗
PubMed2006

Genes controlling plant architecture.

Plant architecture, referring here to the aerial part of a higher plant, is mainly determined by factors affecting shoot branching, plant height and inflorescence morphology. Significant progress has been made in isolating and characterizing genes that are directly involved in the formation of plant architecture, especially those controlling the initiation and outgrowth of axillary buds, elongation of stems and architecture of inflorescences. Most of these genes are conserved between dicotyledonous and monocotyledonous plants, indicating that these plants share similar regulatory pathways to establish their shape. The conservation of these genes makes them of great agronomical importance for improving crop yields.

Flowers↗
PubMed2006

BUD2, encoding an S-adenosylmethionine decarboxylase, is required for Arabidopsis growth and development.

Polyamines are implicated in regulating various developmental processes in plants, but their exact roles and how they govern these processes still remain elusive. We report here an Arabidopsis bushy and dwarf mutant, bud2, which results from the complete deletion of one member of the small gene family that encodes S-adenosylmethionine decarboxylases (SAMDCs) necessary for the formation of the indispensable intermediate in the polyamine biosynthetic pathway. The bud2 plant has enlarged vascular systems in inflorescences, roots, and petioles, and an altered homeostasis of polyamines. The double mutant of bud2 and samdc1, a knockdown mutant of another SAMDC member, is embryo lethal, demonstrating that SAMDCs are essential for plant embryogenesis. Our results suggest that polyamines are required for the normal growth and development of higher plants.

Adenosylmethionine Decarboxylase↗
PubMed2005

Increased expression of MAP KINASE KINASE7 causes deficiency in polar auxin transport and leads to plant architectural abnormality in Arabidopsis.

Polar auxin transport (PAT) plays a crucial role in the regulation of many aspects of plant growth and development. We report the characterization of a semidominant Arabidopsis thaliana bushy and dwarf1 (bud1) mutant. Molecular genetic analysis indicated that the bud1 phenotype is a result of increased expression of Arabidopsis MAP KINASE KINASE7 (MKK7), a member of plant mitogen-activated protein kinase kinase group D. We showed that BUD1/MKK7 is a functional kinase and that the kinase activity is essential for its biological functions. Compared with the wild type, the bud1 plants develop significantly fewer lateral roots, simpler venation patterns, and a quicker and greater curvature in the gravitropism assay. In addition, the bud1 plants have shorter hypocotyls at high temperature (29 degrees C) under light, which is a characteristic feature of defective auxin action. Determination of tritium-labeled indole-3-acetic acid transport showed that the increased expression of MKK7 in bud1 or the repressed expression in MKK7 antisense transgenic plants causes deficiency or enhancement in auxin transport, indicating that MKK7 negatively regulates PAT. This conclusion was further substantiated by genetic and phenotypic analyses of double mutants generated from crosses between bud1 and the auxin-related mutants axr3-3, tir1-1, doc1-1, and atmdr1-1.

Arabidopsis↗
PubMed2005

Towards molecular breeding and improvement of rice in China.

China is the largest producer and consumer of rice in the world and a pioneer in applying hybrid rice technology. Although hybrid rice has contributed greatly to Chinese agriculture in the past decades, its potential to improve grain quality further is being questioned. However, to meet the challenges posed by severe crop damage by pests and diseases, the extensive use of pesticides and chemical fertilizers, and a shortage of water and energy, more elite rice cultivars are needed. In recent years, China has seen continued improvements in rice genetics, powered by functional genomics as a way forward to safeguard its rice production. Here, we briefly review the current status of rice breeding in China through strategies integrating hybrid rice technology, molecular marker-assisted breeding, functional genomics and genetically modified rice.

Breeding↗
PubMed2005

The plant architecture of rice (Oryza sativa).

Plant architecture, a collection of the important agronomic traits that determine grain production in rice, is mainly affected by factors including tillering, plant height and panicle morphology. Recently, significant progress has been made in isolating and collecting of mutants that are defective in rice plant architecture. Although our understanding of the molecular mechanisms that control rice tillering, panicle development and plant height are still limited, new findings have begun to emerge. This review, therefore, summarizes the recent progress in exploring the mechanisms that control rice plant architecture.

Gene Expression Regulation, Developmental↗
PubMed2005

A pilot study of transcription unit analysis in rice using oligonucleotide tiling-path microarray.

As the international efforts to sequence the rice genome are completed, an immediate challenge and opportunity is to comprehensively and accurately define all transcription units in the rice genome. Here we describe a strategy of using high-density oligonucleotide tiling-path microarrays to map transcription of the japonica rice genome. In a pilot experiment to test this approach, one array representing the reverse strand of the last 11.2 Mb sequence of chromosome 10 was analyzed in detail based on a mathematical model developed in this study. Analysis of the array data detected 77% of the reference gene models in a mixture of four RNA populations. Moreover, significant transcriptional activities were found in many of the previously annotated intergenic regions. These preliminary results demonstrate the utility of genome tiling microarrays in evaluating annotated rice gene models and in identifying novel transcription units that will facilitate rice genome annotation.

Carbocyanines↗
PubMed2005

Transcription factors in rice: a genome-wide comparative analysis between monocots and eudicots.

It is not known how representative the Arabidopsis thaliana complement of transcription factors (TFs) is of other plants. The availability of rice (Oryza sativa) genome sequences makes possible a comparative analysis of TFs between monocots and eudicots, the two major monophyletic groups of angiosperms. Here, we identified 1611 TF genes that belong to 37 gene families in rice, comparable to the 1510 in Arabidopsis. Several gene subfamilies, but no families, were found to be lineage-specific. Phylogenetic analyses indicated that nearly half of the TF genes form clear orthologous pairs or groups, which were derived from 383 ancestral genes in the common ancestor of rice and Arabidopsis. Investigating gene duplication mechanisms revealed twelve pairs of large intragenomic duplicated blocks, which account for more than 40% of the rice genome. About 60% of the duplicated TF genes have been retained on duplicated segments. Functional conservation and diversification of TFs across monocot and eudicot lineages are discussed.

Arabidopsis↗
PubMed2004

Genome-wide analysis of the GRAS gene family in rice and Arabidopsis.

Members of the GRAS gene family encode transcriptional regulators that have diverse functions in plant growth and development such as gibberellin signal transduction, root radial patterning, axillary meristem formation, phytochrome A signal transduction, and gametogenesis. Bioinformatic analysis identified 57 and 32 GRAS genes in rice and Arabidopsis, respectively. Here, we provide a complete overview of this gene family, describing the gene structure, gene expression, chromosome localization, protein motif organization, phylogenetic analysis, and comparative analysis between rice and Arabidopsis. Phylogenetic analysis divides the GRAS gene family into eight subfamilies, which have distinct conserved domains and functions. Both genome/segmental duplication and tandem duplication contributed to the expansion of the GRAS gene family in the rice and Arabidopsis genomes. The existence of GRAS-like genes in bryophytes suggests that GRAS is an ancient family of transcription factors, which arose before the appearance of land plants over 400 million years ago.

Amino Acid Motifs↗
PubMed2003

Control of tillering in rice.

Tillering in rice (Oryza sativa L.) is an important agronomic trait for grain production, and also a model system for the study of branching in monocotyledonous plants. Rice tiller is a specialized grain-bearing branch that is formed on the unelongated basal internode and grows independently of the mother stem (culm) by means of its own adventitious roots. Rice tillering occurs in a two-stage process: the formation of an axillary bud at each leaf axil and its subsequent outgrowth. Although the morphology and histology and some mutants of rice tillering have been well described, the molecular mechanism of rice tillering remains to be elucidated. Here we report the isolation and characterization of MONOCULM 1 (MOC1), a gene that is important in the control of rice tillering. The moc1 mutant plants have only a main culm without any tillers owing to a defect in the formation of tiller buds. MOC1 encodes a putative GRAS family nuclear protein that is expressed mainly in the axillary buds and functions to initiate axillary buds and to promote their outgrowth.

Agriculture↗
PubMed2003

BRITTLE CULM1, which encodes a COBRA-like protein, affects the mechanical properties of rice plants.

Plant mechanical strength is an important agronomic trait. To understand the molecular mechanism that controls the plant mechanical strength of crops, we characterized the classic rice mutant brittle culm1 (bc1) and isolated BC1 using a map-based cloning approach. BC1, which encodes a COBRA-like protein, is expressed mainly in developing sclerenchyma cells and in vascular bundles of rice. In these types of cells, mutations in BC1 cause not only a reduction in cell wall thickness and cellulose content but also an increase in lignin level, suggesting that BC1, a gene that controls the mechanical strength of monocots, plays an important role in the biosynthesis of the cell walls of mechanical tissues.

Amino Acid Sequence↗
PubMed2002

Sequence and analysis of rice chromosome 4.

Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O. sativa, one of the first two rice chromosomes to be sequenced completely. The finished sequence spans 34.6 Mb and represents 97.3% of the chromosome. In addition, we report the longest known sequence for a plant centromere, a completely sequenced contig of 1.16 Mb corresponding to the centromeric region of chromosome 4. We predict 4,658 protein coding genes and 70 transfer RNA genes. A total of 1,681 predicted genes match available unique rice expressed sequence tags. Transposable elements have a pronounced bias towards the euchromatic regions, indicating a close correlation of their distributions to genes along the chromosome. Comparative genome analysis between cultivated rice subspecies shows that there is an overall syntenic relationship between the chromosomes and divergence at the level of single-nucleotide polymorphisms and insertions and deletions. By contrast, there is little conservation in gene order between rice and Arabidopsis.

Arabidopsis↗
PubMed2002

Silencing of phosphoethanolamine N-methyltransferase results in temperature-sensitive male sterility and salt hypersensitivity in Arabidopsis.

S-Adenosyl-L-methionine:phosphoethanolamine N-methyltransferase (PEAMT; EC 2.1.1.103) catalyzes the key step in choline (Cho) biosynthesis, the N-methylation of phosphoethanolamine. Cho is a vital precursor of the membrane phospholipid phosphatidylcholine, which accounts for 40 to 60% of lipids in nonplastid plant membranes. Certain plants use Cho to produce the osmoprotectant glycine betaine, which confers resistance to salinity, drought, and other stresses. An Arabidopsis mutant, t365, in which the PEAMT gene is silenced, was identified using a new sense/antisense RNA expression system. t365 mutant plants displayed multiple morphological phenotypes, including pale-green leaves, early senescence, and temperature-sensitive male sterility. Moreover, t365 mutant plants produced much less Cho and were hypersensitive to salinity. These results demonstrate that Cho biosynthesis not only plays an important role in plant growth and development but also contributes to tolerance to environmental stresses. The temperature-sensitive male sterility caused by PEAMT silencing may have a potential application in agriculture for engineering temperature-sensitive male sterility in important crop plants.

Adaptation, Physiological↗