Main conclusion
The function of
SQUAMOSA PROMOTER-BINDING PROTEIN-BOX
gene
TaSPL14
in wheat is similar to that of
OsSPL14
in rice in regulating plant height, panicle length, spikelet number, and ...thousand-grain weight of wheat, but differs during tiller development. TaSPL14 may regulate spike development via ethylene-response gene
EIN3-LIKE 1
(
TaEIL1
),
ETHYLENE-RESPONSIVE TRANSCRIPTION FACTOR 2.11
(
TaRAP2.11
), and
ETHYLENE-RESPONSIVE TRANSCRIPTION FACTOR 1
(
TaERF1
), but not
DENSE AND ERECT PANICLE 1
(
TaDEP1
) in wheat.
The
SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE
gene
OsSPL14
from rice is considered to be a major determinant of ideal plant architecture consisting of few unproductive tillers, more grains per spike, and high resistance of stems to lodging. However, the function of its orthologous gene,
TaSPL14
, in wheat is unknown. Here, we reported the functional similarities and differences between
TaSPL14
and
OsSPL14
. Similar to
OsSPL14
knock-outs in rice, wheat
TaSPL14
knock-out plants exhibited decreased plant height, panicle length, spikelet number, and thousand-grain weight. In contrast to
OsSPL14
, however,
TaSPL14
did not affect tiller number. Transcriptome analysis revealed that the expression of genes related to ethylene response was significantly decreased in young spikes of
TaSPL14
knock-out lines as compared with wild type. TaSPL14 directly binds to the promoters of the ethylene-response genes
TaEIL1
,
TaRAP2.11,
and
TaERF1,
and promotes their expression, suggesting that
TaSPL14
might regulate wheat spike development via the ethylene-response pathway. The elucidation of
TaSPL14
will contribute to understanding of the molecular mechanisms that underlie wheat plant architecture.
Natural rubber (cis-1,4-polyisoprene, NR) is an important raw material utilized widely in the manufacturing of medical, agricultural, and industrial products. Rubber tree (
) and several alternative ...rubber-producing plants (
,
, and
) have the capability to produce high-quality NR. With the progress of genome sequencing, similar rubber biosynthesis pathways have been discovered among different rubber-producing plant species. NR is synthesized and stored in rubber particles, which are specialized organelles comprising a hydrophobic NR core surrounded by a lipid monolayer and membrane-bound proteins. The rubber transferase complex is considered to be the pivotal enzyme involved in catalyzing NR biosynthesis. However, the exact compositions of the RT complex in rubber-producing plants remain elusive and poorly understood. Here, we review the progress of genome sequencing, natural rubber biosynthesis, and the components of the RT complex in rubber-producing plants. We emphasize that identifying the detailed components of the RT complex holds great significance for exploring the mechanism of NR biosynthesis and accelerating molecular breeding in rubber-producing plants.
There were significant discrepancies in the intensity estimations of Super Typhoon Lekima (2019) among the China Meteorological Administration (CMA), the United States Joint Typhoon Warning Center ...(JTWC), and the Japan Meteorological Agency (JMA) data sets, with a maximum difference of over 12 m/s and 16 m/s between the JTWC data set and the CMA and JMA data sets, respectively. During the intensification phase, disagreement on the maximum sustained wind (MSW) between these agencies was due to the use of different conversion tables for the current intensity number (CI) estimated by Dvorak technique-MSW. In addition, CI discrepancies and different available observational data were also important contributors to the different intensities estimated during the Lekima's decay phase before landfall. The ability of various methods to minimize these discrepancies was evaluated in this study. Both the linear factor multiplication method and the remapping method using the same CI-MSW conversion table have substantially abilities to reduce intensity discrepancies, with the latter method being more effective. However, these improvements only hold for the intensification phase in the ocean. The CMA data set had more complete and accurate intensity estimations when Lekima made landfall in China. After its landfall, the intensity estimate of the CMA was comparable to that of the JMA, which differed greatly from that of the JTWC.
MicroRNAs (miRNAs) are widely involved in various aspects of plant growth and development. However, how miRNAs and their targets regulate natural rubber metabolism remains unclear in the ...rubber-producing dandelions, which are being developed as alternative commercial sources of natural rubber. Here, we combined small RNA sequencing, degradome sequencing, target gene prediction, and mRNA sequencing to identify miRNAs and their targets in two dandelion species, the high rubber-yielding
Taraxacum kok-saghyz
(Tk) and the low rubber-yielding
T. spadiceum
(Ts). A total of 142 miRNAs, including 108 known and 34 novel ones, were discovered, with 53 identified as differentially expressed (DE) between the latex of Tk and Ts. Degradome sequencing identified 145 targets corresponding to 74 miRNAs. TAPIR and psRNATarget, respectively, predicted 165 and 164 non-redundant targets for the 53 aforementioned DE miRNAs. Gene ontology (GO) enrichment analysis indicated the DE miRNAs and their targets might affect natural rubber production via regulating macromolecular biosynthesis and metabolism in latex. Four critical types of regulatory modules, including miR172-AP2/ERF, miR164-NAC, miR160-ARF, and miRN19-protein kinase, were identified and their interaction networks were constructed, indicating a potential involvement in natural rubber production. The findings and the large miRNA dataset presented here are beneficial to further deciphering the roles of miRNAs in the biosynthesis of natural rubber and medicinal metabolites in dandelion.
Transgenic technology is a crucial tool for gene functional analysis and targeted genetic modification in the para rubber tree (
). However, low efficiency of plant regeneration via somatic ...embryogenesis remains a bottleneck of successful genetic transformation in
. Enhancing expression of
(
)-
(
) has been reported to significantly improve shoot and embryo regeneration in multiple crops. Here, we identified endogenous
and
from the rubber clone Reyan7-33-97, the expressions of which dramatically increased along with somatic embryo (SE) production. Intriguingly, overexpression of
or
markedly enhanced the efficiency of embryogenesis in two
callus lines with contrasting rates of SE production. Transcriptional profiling revealed that the genes involved in jasmonic acid response were up-regulated, whereas those in ethylene biosynthesis and response as well as the
-adenosylmethionine-dependent methyltransferase activity were down-regulated in
- and
-overexpressing
embryos. These findings open up a new avenue for improving SE production in rubber tree, and help to unravel the underlying mechanisms of HbGRF4-enhanced somatic embryogenesis.
Key message
QTL controlling flag leaf length, flag leaf width, flag leaf area and flag leaf angle were mapped in wheat.
This study aimed to advance our understanding of the genetic mechanisms ...underlying morphological traits of the flag leaves of wheat (
Triticum aestivum
L.). A recombinant inbred line (RIL) population derived from ND3331 and the Tibetan semi-wild wheat Zang1817 was used to identify quantitative trait loci (QTLs) controlling flag leaf length (FLL), flag leaf width (FLW), flag leaf area (FLA), and flag leaf angle (FLANG). Using an available simple sequence repeat genetic linkage map, 23 putative QTLs for FLL, FLW, FLA, and FLANG were detected on chromosomes 1B, 2B, 3A, 3D, 4B, 5A, 6B, 7B, and 7D. Individual QTL explained 4.3–68.52% of the phenotypic variance in different environments. Four QTLs for FLL, two for FLW, four for FLA, and five for FLANG were detected in at least two environments. Positive alleles of 17 QTLs for flag leaf-related traits originated from ND3331 and 6 originated from Zang1817. QTLs with pleiotropic effects or multiple linked QTL were also identified on chromosomes 1B, 4B, and 5A; these are potential target regions for fine-mapping and marker-assisted selection in wheat breeding programs.
Developing carbon encapsulated magnetic composites with rational design of microstructure for achieving high-performance electromagnetic wave (EMW) absorption in a facile, sustainable, and ...energy-efficiency approach is highly demanded yet remains challenging. Here, a type of N-doped carbon nanotube (CNT) encapsulated CoNi alloy nanocomposites with diverse heterostructures are synthesized via the facile, sustainable autocatalytic pyrolysis of porous CoNi-layered double hydroxide/melamine. Specifically, the formation mechanism of the encapsulated structure and the effects of heterogenous microstructure and composition on the EMW absorption performance are ascertained. With the presence of melamine, CoNi alloy emerges its autocatalysis effect to generate N-doped CNTs, leading to unique heterostructure and high oxidation stability. The abundant heterogeneous interfaces induce strong interfacial polarization to EMWs and optimize impedance matching characteristic. Combined with the inherent high conductive and magnetic loss capabilities, the nanocomposites accomplish a high-efficiency EMW absorption performance even at a low filling ratio. The minimum reflection loss of -84.0 dB at the thickness of 3.2 mm and a maximum effective bandwidth of 4.3 GHz are obtained, comparable to the best EMW absorbers. Integrated with the facile, controllable, and sustainable preparation approach of the heterogenous nanocomposites, the work shows a great promise of the nanocarbon encapsulation protocol for achieving lightweight, high-performance EMW absorption materials.
The increasing demand for high-load compressors necessitates research and design of supersonic compressor blades. Geometric deformations of the blades resulting from manufacturing errors introduce ...uncertainties in their aerodynamic characteristics. For uncertainty analysis, Polynomial Chaos Expansion (PCE) has gained popularity among engineers in various disciplines. However, as the number of random variables used to describe uncertainties increases, the efficiency of the PCE method diminishes. To overcome this limitation, an Efficient Sparse Surrogate Model (ESSM) was first proposed. The ESSM combines PCE to approximate global characteristics and Gaussian process modeling to capture local variability, resulting in a highly accurate model. Additionally, by utilizing an iteratively diffeomorphic modulation under observable response preserving homotopy, important PCE basis functions are adaptively selected, leading to a sparse surrogate model that significantly reduces the required training samples. Then using the ESSM, efficient Uncertainty Quantification (UQ) and global sensitivity analysis were conducted to evaluate the impact of uncertain geometric deformations on the aerodynamic characteristics of a supersonic compressor cascade. Principal Component Analysis (PCA) was employed in conjunction with an Improved Class Shape Transformation (ICST) to characterize geometric deformations caused by manufacturing errors. The proposed ICST method exhibits enhanced accuracy in fitting near the leading and trailing edges compared to the CST method. PCA enables a 50% reduction in the number of random variables needed to describe geometric deformations. The UQ results establish a quantitative correlation between geometric deformations and supersonic aerodynamics, and the sensitivity analysis identifies some specific forms of geometric deformations that significantly impact the aerodynamics. Finally, the study investigated the flow mechanisms associated with typical geometric deformation forms, further providing recommendations for manufacturing and testing of supersonic blades to prevent performance deterioration.
In grass crops, leaf angle is determined by development of the lamina joint, the tissue connecting the leaf blade and sheath, and is closely related to crop architecture and yield. In this study, we ...identified a mutant generated by fast neutron radiation that exhibited an erect leaf phenotype caused by defects in lamina joint development. Map-based cloning revealed that the gene
, encoding a SQUAMOSA PROMOTER BINDING-LIKE (SPL) protein, is deleted in this mutant.
knock-out mutants exhibit erect leaves due to loss of the lamina joint, compact architecture, and increased spike number especially in high planting density, suggesting similarity with its
homologs in maize (
) and rice (
). Hence,
could be a robust target for plant architecture improvement in grass species. Common wheat (
, 2
= 6× = 42; BBAADD) is an allohexaploid containing A, B, and D subgenomes and the homeologous gene of
from the D subgenome contributes to the length of the lamina joint to a greater extent than that from the A and B subgenomes. Comparison of the transcriptome between the
mutant and the wild type revealed that
is involved in the activation of genes related to auxin and brassinosteroid pathways and cell elongation. TaSPL8 binds to the promoters of the
gene and of the brassinosteroid biogenesis gene
and activates their expression. These results indicate that
might regulate lamina joint development through auxin signaling and the brassinosteroid biosynthesis pathway.
Transgenic technology is a crucial tool for gene functional analysis and targeted genetic modification in the para rubber tree (Hevea brasiliensis). However, low efficiency of plant regeneration via ...somatic embryogenesis remains a bottleneck of successful genetic transformation in H. brasiliensis. Enhancing expression of GROWTH-REGULATING FACTOR 4 (GRF4)-GRF-INTERACTING FACTOR 1 (GIF1) has been reported to significantly improve shoot and embryo regeneration in multiple crops. Here, we identified endogenous HbGRF4 and HbGIF1 from the rubber clone Reyan7-33-97, the expressions of which dramatically increased along with somatic embryo (SE) production. Intriguingly, overexpression of HbGRF4 or HbGRF4-HbGIF1 markedly enhanced the efficiency of embryogenesis in two H. brasiliensis callus lines with contrasting rates of SE production. Transcriptional profiling revealed that the genes involved in jasmonic acid response were up-regulated, whereas those in ethylene biosynthesis and response as well as the S-adenosylmethionine-dependent methyltransferase activity were down-regulated in HbGRF4- and HbGRF4-HbGIF1-overexpressing H. brasiliensis embryos. These findings open up a new avenue for improving SE production in rubber tree, and help to unravel the underlying mechanisms of HbGRF4-enhanced somatic embryogenesis.
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