Basic helix-loop-helix (bHLH) proteins, one of the most important and largest transcription factor family in plants, play important roles in regulating growth and development, stress response. In ...recent years, many bHLH family genes have been identified and characterized in woody plants. However, a systematic analysis of the bHLH gene family has not been reported in Ginkgo biloba, the oldest relic plant species. In this study, we identifed a total of 85 GbbHLH genes from the genomic and transcriptomic databases of G. biloba, which were classified into 17 subfamilies based on the phylogenetic analysis. Gene structures analysis indicated that the number of exon-intron range in GbbHLHs from 0 to 12. The MEME analysis showed that two conserved motifs, motif 1 and motif 2, distributed in most GbbHLH protein. Subcellular localization analysis exhibited that most GbbHLHs located in nucleus and a few GbbHLHs were distributed in chloroplast, plasma membrane and peroxisome. Promoter cis-element analysis revealed that most of the GbbHLH genes contained abundant cis-elements that involved in plant growth and development, secondary metabolism biosynthesis, various abiotic stresses response. In addition, correlation analysis between gene expression and flavonoid content screened seven candidate GbbHLH genes involved in flavonoid biosynthesis, providing the targeted gene encoding transcript factor for increase the flavonoid production through genetic engineering in G. biloba.
Ginkgo biloba L. is an ancient relict plant with rich pharmacological activity and nutritional value, and its main physiologically active components are flavonoids and terpene lactones. The bZIP gene ...family is one of the largest gene families in plants and regulates many processes including pathogen defense, secondary metabolism, stress response, seed maturation, and flower development. In this study, genome-wide distribution of the bZIP transcription factors was screened from G. biloba database in silico analysis. A total of 40 bZIP genes were identified in G. biloba and were divided into 10 subclasses. GbbZIP members in the same group share a similar gene structure, number of introns and exons, and motif distribution. Analysis of tissue expression pattern based on transcriptome indicated that GbbZIP08 and GbbZIP15 were most highly expressed in mature leaf. And the expression level of GbbZIP13 was high in all eight tissues. Correlation analysis and phylogenetic tree analysis suggested that GbbZIP08 and GbbZIP15 might be involved in the flavonoid biosynthesis. The transcriptional levels of 20 GbbZIP genes after SA, MeJA, and low temperature treatment were analyzed by qRT-PCR. The expression level of GbbZIP08 was significantly upregulated under 4°C. Protein-protein interaction network analysis indicated that GbbZIP09 might participate in seed germination by interacting with GbbZIP32. Based on transcriptome and degradome data, we found that 32 out of 117 miRNAs were annotated to 17 miRNA families. The results of this study may provide a theoretical foundation for the functional validation of GbbZIP genes in the future.
Camellia japonica
petals are colorful, rich in anthocyanins, and possess important ornamental, edible, and medicinal value. However, the regulatory mechanism of anthocyanin accumulation in
C. ...japonica
is still unclear. In this study, an integrative analysis of the metabolome and transcriptome was conducted in five
C. japonica
cultivars with different petal colors. Overall, a total of 187 flavonoids were identified (including 25 anthocyanins), and 11 anthocyanins were markedly differentially accumulated among these petals, contributing to the different petal colors in
C. japonica
. Moreover, cyanidin-3-
O-
(6
″
-
O-
malonyl) glucoside was confirmed as the main contributor to the red petal phenotype, while cyanidin-3-
O-
rutinoside, peonidin-3-
O-
glucoside, cyanidin-3-
O-
glucoside, and pelargonidin-3-
O-
glucoside were responsible for the deep coloration of the
C. japonica
petals. Furthermore, a total of 12,531 differentially expressed genes (DEGs) and overlapping DEGs (634 DEGs) were identified by RNA sequencing, and the correlation between the expression level of the DEGs and the anthocyanin content was explored. The candidate genes regulating anthocyanin accumulation in the
C. japonica
petals were identified and included 37 structural genes (especially
CjANS
and
Cj4CL
), 18 keys differentially expressed transcription factors (such as
GATA
,
MYB
,
bHLH
,
WRKY
, and
NAC
), and 16 other regulators (mainly including transporter proteins, zinc-finger proteins, and others). Our results provide new insights for elucidating the function of anthocyanins in
C. japonica
petal color expression.
Fraxinus hupehensis is an endangered tree species that is endemic to in China; the species has very high commercial value because of its intricate shape and potential to improve and protect the ...environment. Its seeds show very low germination rates in natural conditions. Preliminary experiments indicated that gibberellin (GA
) effectively stimulated the seed germination of F. hupehensis. However, little is known about the physiological and molecular mechanisms underlying the effect of GA
on F. hupehensis seed germination.
We compared dormant seeds (CK group) and germinated seeds after treatment with water (W group) and GA
(G group) in terms of seed vigor and several other physiological indicators related to germination, hormone content, and transcriptomics. Results showed that GA
treatment increases seed vigor, energy requirements, and trans-Zetain (ZT) and GA
contents but decreases sugar and abscisic acid (ABA) contents. A total of 116,932 unigenes were obtained from F. hupehensis transcriptome. RNA-seq analysis identified 31,856, 33,188 and 2056 differentially expressed genes (DEGs) between the W and CK groups, the G and CK groups, and the G and W groups, respectively. Up-regulation of eight selected DEGs of the glycolytic pathway accelerated the oxidative decomposition of sugar to release energy for germination. Up-regulated genes involved in ZT (two genes) and GA
(one gene) biosynthesis, ABA degradation pathway (one gene), and ABA signal transduction (two genes) may contribute to seed germination. Two down-regulated genes associated with GA
signal transduction were also observed in the G group. GA
-regulated genes may alter hormone levels to facilitate germination. Candidate transcription factors played important roles in GA
-promoted F. hupehensis seed germination, and Quantitative Real-time PCR (qRT-PCR) analysis verified the expression patterns of these genes.
Exogenous GA
increased the germination rate, vigor, and water absorption rate of F. hupehensis seeds. Our results provide novel insights into the transcriptional regulation mechanism of effect of exogenous GA
on F. hupehensis seed germination. The transcriptome data generated in this study may be used for further molecular research on this unique species.
3-Hydroxy-3-methylglutaryl-CoA synthase (HMGS) is one of the rate-limiting enzymes in the mevalonate pathway as it catalyzes the condensation of acetoacetyl-CoA to form ...3-hydroxy-3-methylglutaryl-CoA. In this study, A
gene (designated as
) was cloned from
for the first time.
contained a 1422-bp open-reading frame encoding 474 amino acids. Comparative and bioinformatics analysis revealed that GbHMGS1 was extensively homologous to HMGSs from other plant species. Phylogenetic analysis indicated that the GbHMGS1 belonged to the plant HMGS superfamily, sharing a common evolutionary ancestor with other HMGSs, and had a further relationship with other gymnosperm species. The yeast complement assay of GbHMGS1 in
-deficient
strain YSC6274 demonstrated that
gene encodes a functional HMGS enzyme. The recombinant protein of GbHMGS1 was successfully expressed in
. The in vitro enzyme activity assay showed that the
and
values of GbHMGS1 were 195.4 min
and 689 μM, respectively.
was constitutively expressed in all tested tissues, including the roots, stems, leaves, female flowers, male flowers and fruits. The transcript accumulation for
was highest in the leaves. Expression profiling analyses revealed that
expression was induced by abiotic stresses (ultraviolet B and cold) and hormone treatments (salicylic acid, methyl jasmonate, and ethephon) in
, indicating that
gene was involved in the response to environmental stresses and plant hormones.
Abstract
In this paper, a novel Resistive Random‐Access Memory (RRAM) read circuit has been designed and verified by simulation based on the RRAM model and parasitic capacitance of the circuit. ...Simulation results demonstrate the feasibility and effectiveness of the proposed circuit, with accurate reading of RRAM states and fast reading speed in the nanosecond range. The sense margin of the proposed circuit has improved as the array size increases, enhancing its application for advanced node RRAM array manufacture. Compared with conventional circuits, the proposed circuit achieved power consumption reduction of 6% and area reduction of 46.9 um
2
, resulting in a 97.5% reduction in area, providing an effective solution to address the cost and chip size challenges associated with RRAM industrialization.
Plant-specific TCP transcription factors play an essential role in plant growth and development. They can regulate leaf curvature, flower symmetry and the synthesis of secondary metabolites. The ...flavonoids in Ginkgo biloba leaf are one of the main medicinally bioactivate compounds, which have pharmacological and beneficial health effects for humans. In this study, a total of 13 TCP genes were identified in G. biloba, and 5 of them belonged to PCF subclades (GbTCP03, GbTCP07, GbTCP05, GbTCP13, GbTCP02) while others belonged to CIN (GbTCP01, GbTCP04, GbTCP06, GbTCP08, GbTCP09, GbTCP10, GbTCP11, GbTCP12) subclades according to phylogenetic analysis. Numerous cis-acting elements related to various biotic and abiotic signals were predicted on the promoters by cis-element analysis, suggesting that the expression of GbTCPs might be co-regulated by multiple signals. Transcript abundance analysis exhibited that most of GbTCPs responded to multiple phytohormones. Among them, the relative expression levels of GbTCP06, GbTCP11, and GbTCP13 were found to be significantly influenced by exogenous ABA, SA and MeJA application. In addition, a total of 126 miRNAs were predicted to target 9 TCPs (including GbTCP01, GbTCP02, GbTCP04, GbTCP05, GbTCP06, GbTCP08, GbTCP11, GbTCP12, GbTCP13). The correlation analysis between the expression level of GbTCPs and the flavonoid contents showed that GbTCP03, GbTCP04, GbTCP07 might involve in flavonoid biosynthesis in G. biloba. In short, this study mainly provided a theoretical foundation for better understanding the potential function of TCPs in G. biloba.
As unique secondary metabolites of
Ginkgo biloba
L. and relics of Ginkgoaceae, terpene trilactones (TTLs) possess great medicinal value. In this study, we investigated the effects of ultraviolet (UV) ...irradiation, cold stress (4 °C), and exogenous hormone treatment on TTLs and key genes expression in ginkgo leaves in annual potted ginkgo seedlings subjected to different stress treatments. The processing conditions were as follows: UV treatment (1500 μJ/m
2
) for 0, 8, 16, 24, and 48 h; cold stress at 4 °C, 400 µmol photons m
−2
s
−1
; 100 μM abscisic acid (ABA); 100 μM methyl jasmonate (MeJA); 10 mM salicylic acid (SA); and 10 mM ethephon (ETH) treatments for 0, 2, 4, 6, and 8 days. Results of evaporative light-scattering detector–high-performance liquid chromatography showed that UV, cold stress, ABA, SA, MeJA, and ETH treatments increased the TTL content at various levels and up to 21.9%. The relationships among the expression levels of the key enzyme genes
GbDXS
,
GbGGPPS
,
GbLPS
, and
GbMVD
in the TTL biosynthesis pathway were also analyzed. Changes in the TTL content and expression levels of the key genes were significantly and positively correlated with TTL content. UV, cold stress, ABA, SA, MeJA, and ETH were found to increase the TTL content by upregulating the expression of the key genes. This study aimed to reveal the molecular mechanism through which TTLs are synthesized. The results can also provide theoretical guidance for the application of treatment methods to increase TTL content.
Carotenoids are naturally occurring tetraterpenoids that play a key role in fruit coloration, and yellow peaches are one of the best sources of carotenoid intake. MYB transcription factors are one of ...the largest families in plants and play an important role in the regulation of plant secondary metabolite biosynthesis. However, peach MYB family genes have not been fully analyzed, and in particular, MYBs that regulate carotenoid biosynthesis have not been fully characterized. In this study, 190 peach MYB genes, containing 68 1R-MYBs, 118 2R-MYBs, 3 3R-MYBs, and 1 4R-MYB, were identified at the genome level using bioinformatics methods. These 190 MYBs were classified into 27 subfamilies based on their phylogenetic relationships with Arabidopsis thaliana MYB family members, and they were unevenly distributed across eight chromosomes. MYB genes of the same subfamily exhibit similar but not identical gene structures and conserved motifs. The promoter regions contain cis-acting elements associated with stress response, hormone response, and plant growth and development. There were 54 collinear pairs of MYB genes in the peach genome, compared with 233 and 221 collinear pairs with Rosa chinensis and Arabidopsis, respectively. Thirteen differentially expressed genes in the carotenoid biosynthesis pathway in yellow peach were identified by transcriptome sequencing and contained MYB binding sites on their promoters. Based on a phylogenetic analysis, we identified 13 PpMYBs that may be involved in carotenoid biosynthesis, and a correlation analysis revealed that they regulate carotenoid accumulation by positively or negatively regulating the expression of carotenoid biosynthetic genes. Further degradome sequencing screened that mdm-miR858 was able to target PpMYB17 and PpMYB126 involved in the regulation of carotenoid biosynthesis. Our findings provide new insights into the potential role of MYB transcription factors in carotenoid biosynthesis and provide a theoretical basis for their molecular mechanisms.
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