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Zhi-Yong Wang

Publications and source records attributed to Zhi-Yong Wang.

18 recordsLinked to original sources
PubMed2026

Deciphering the Protein Phosphorylation Dynamics Triggered by Seconds of Force Stimulation.

Plants perceive mechanical forces through phosphosignaling networks, but their relationship with gravity signaling remains elusive. To dissect gravity force signaling components, we performed SILIA-based phosphoproteomics on Arabidopsis aerial organs subjected to 20-s inversion or 30-s gravistimulation, identifying 2,733 and 2,878 phosphoproteins, respectively. Quantitative analysis revealed 34 significantly regulated phosphoproteins specific to inversion and 52 specific to gravistimulation. Inversion-specific phosphoproteins, associated with the initial calcium code, likely mediate calcium signals through EF-hand proteins, CPK1, and calmodulin-interacting proteins, potentially intersecting with receptor-like kinase-initiated MAPK cascades via RAF15 and MKK1/2 to induce gravitropic responses. Gravistimulation-specific phosphoproteins, linked to the secondary calcium code, function in calcium signaling/homeostasis (ACA8, ZAC, IQD2, ANNAT1), membrane vesicle trafficking (ABCG36, ARF-GAP8), and lipid signaling (PIP5K8/9), supporting auxin transport and stress signal transduction. Immunoblot validation confirmed treatment-associated phosphosites pS108-PATL3 and pS107-TREPH2, along with inversion-specific pS1145-ATEH2, exhibiting stem-specific phosphorylation enhancement and force-discriminatory responses. Functional analysis identified the integrin-like protein GREPH1 as a key gravitropism regulator, with greph1 mutants displaying reduced inflorescence stem gravicurvature. Notably, hyperphosphorylation of pS107-TREPH2 and pS1145-ATEH2 peaked at 20 to 50 s in greph1 mutants but persisted from 20 s to 2 h in WT plants. These findings establish a stem-enriched phosphorylation code for gravity force discrimination, with GREPH1 modulating spatiotemporal phosphoprotein dynamics and shoot gravicurvature, potentially functioning as a receptor reminiscent of sedimenting plastids.

Arabidopsis↗
PubMed2006

Inhibition of tetanically sciatic stimulation-induced LTP of spinal neurons and Fos expression by disrupting glutamate transporter GLT-1.

Tetanic stimulation of the sciatic nerve produces spinal long-term potentiation (LTP) of C-fiber evoked field potentials, which is NMDA dependent and may be the substrate of inflammation- or nerve injury-produced central sensitization. Glial glutamate transporter GLT-1 has been considered as an important regulator of excitatory synaptic transmission and nociception. In the present study, we investigated the effects of GLT-1 on the spinal LTP and Fos expression induced by tetanically sciatic stimulation. Intrathecal administration of dihydrokainate (DHK), a GLT-1 selective inhibitor, partially inhibited (0.1 mM) or completely blocked (3.0 mM) the spinal LTP, which may be related to an accumulation of extracellular glutamate. Intrathecal DHK (3.0 mM) also suppressed tetanic stimulation-induced spinal Fos expression. Double immunofluorescence showed no Fos expression in glial fibrillary acidic protein (GFAP)-positive cells, and the cell DNA fragment study failed to detect a significant apoptosis of spinal neurons. These results suggest that disruption of GLT-1 may be associated with the inhibition of functional activation of spinal neurons expressing Fos, but not with glutamate excitotoxicity. In conclusion, glial GLT-1 may play an important role in tetanically sciatic stimulation-induced LTP of spinal nociceptive neurons via the regulation of extracellular levels of glutamate to an appropriate concentration.

Animals↗
PubMed2006

Transcriptome profiling, molecular biological, and physiological studies reveal a major role for ethylene in cotton fiber cell elongation.

Upland cotton (Gossypium hirsutum) produces the most widely used natural fibers, yet the regulatory mechanisms governing fiber cell elongation are not well understood. Through sequencing of a cotton fiber cDNA library and subsequent microarray analysis, we found that ethylene biosynthesis is one of the most significantly upregulated biochemical pathways during fiber elongation. The 1-Aminocyclopropane-1-Carboxylic Acid Oxidase1-3 (ACO1-3) genes responsible for ethylene production were expressed at significantly higher levels during this growth stage. The amount of ethylene released from cultured ovules correlated with ACO expression and the rate of fiber growth. Exogenously applied ethylene promoted robust fiber cell expansion, whereas its biosynthetic inhibitor l-(2-aminoethoxyvinyl)-glycine (AVG) specifically suppressed fiber growth. The brassinosteroid (BR) biosynthetic pathway was modestly upregulated during this growth stage, and treatment with BR or its biosynthetic inhibitor brassinazole (BRZ) also promoted or inhibited, respectively, fiber growth. However, the effect of ethylene treatment was much stronger than that of BR, and the inhibitory effect of BRZ on fiber cells could be overcome by ethylene, but the AVG effect was much less reversed by BR. These results indicate that ethylene plays a major role in promoting cotton fiber elongation. Furthermore, ethylene may promote cell elongation by increasing the expression of sucrose synthase, tubulin, and expansin genes.

Amino Acids, Cyclic↗
PubMed2006

The brassinosteroid signal transduction pathway.

Steroids function as signaling molecules in both animals and plants. While animal steroid hormones are perceived by nuclear receptor family of transcription factors, brassinosteroids (BR) in plants are perceived by a cell surface receptor kinase, BRI1. Recent studies have demonstrated that BR binding to the extracellular domain of BRI1 induces kinase activation and dimerization with another receptor kinase, BAK1. Activated BRI1 or BAK1 then regulate, possibly indirectly, the activities of BIN2 kinase and/or BSU1 phosphatase, which directly regulate the phosphorylation status and nuclear accumulation of two homologous transcription factors, BZR1 and BES1. BZR1 and BES1 directly bind to promoters of BR responsive genes to regulate their expression. The BR signaling pathway has become a paradigm for both receptor kinase signaling in plants and steroid signaling by cell surface receptors in general.

Brassinosteroids↗
PubMed2006

[Microsatellite marker analysis of gynogenesis by artificial induction in Pseudosciaena crocea].

Gynogenesis was induced in two groups of Pseudosciaena crocea by the cool-shock and hydrostatic pressure method. The 24 fry in the gynogenetic families G1 and G2, 20 fry in their contrast groups and their parents were PCR amplified using 6 pairs of microsatellite marker primers LYC0002, LYC0003, LYC0013, LYC0012, LYC0004 and LYC0006 and analyzed. The results showed that the effect of cool-shock method, obtained a hatching rate of 35.3%, and a survival rate of 9.9% at 45 days, was obviously better than hydrostatic pressure method. Four pairs of primers could amplify clearly distinct parental bands. The results of primers LYC0012 and LYC0006 revealed no male gene in G1, suggesting they all derived from gynogenesis. Amplification using primers LYC0013 and LYC0004 in G2 revealed the presence of male genes in 3 individuals, suggesting they came from normal fertilization. The homozygosity ratio of the offspring from the two families was 87.5% and 76.2% and the average was 81.9%. They were 0 respectively in their contrast groups. The homozygous ratio of gene improved for 81.9% by gynogenesis. This study shows that gynogenesis is an effective method to promote gene purification In addition, microsatellite marker technique is an effective method of gynogenesis verification and genetic analysis.

Animals↗
PubMed2005

BZR1 is a transcriptional repressor with dual roles in brassinosteroid homeostasis and growth responses.

Brassinosteroid (BR) homeostasis and signaling are crucial for normal growth and development of plants. BR signaling through cell-surface receptor kinases and intracellular components leads to dephosphorylation and accumulation of the nuclear protein BZR1. How BR signaling regulates gene expression, however, remains unknown. Here we show that BZR1 is a transcriptional repressor that has a previously unknown DNA binding domain and binds directly to the promoters of feedback-regulated BR biosynthetic genes. Microarray analyses identified additional potential targets of BZR1 and illustrated, together with physiological studies, that BZR1 coordinates BR homeostasis and signaling by playing dual roles in regulating BR biosynthesis and downstream growth responses.

Arabidopsis↗
PubMed2005

[Inhibitory effect of hTERT dsRNA on telomerase activity in lung carcinoma cell line A549].

BACKGROUND & OBJECTIVE: RNA interference (RNAi) is a new technology in gene study. The mechanism of RNAi is that double-stranded RNA (dsRNA) can band target mRNA and decompose it. This study was to assess possibility and specificity of dsRNA on suppressing human telomerase reverse transcriptase (hTERT) in lung carcinoma cells, investigate its effect on cell proliferation to confirm whether it has unspecific killing activity on mammalian cells, and explore its application in lung cancer research and treatment. METHODS: Sequences of 2 exons and 1 intron of hTERT gene were amplified by reverse transcription-polymerase chain reaction (RT-PCR) or PCR. The sense and antisense cDNA sequences were connected in a tandem manner, and the whole fragment was inserted into pCI-neo mammalian expression vector to construct the dsRNA expression vector, and then transfected into lung carcinoma cell line A549. The expression of hTERT was detected by RT-PCR and Western blot. Telomerase activity was measured by telomerase repeat amplification protocol (TRAP). Cell morphology was observed, and cell proliferation was assessed under invert microscope. RESULTS: After transfection of 2 exon fragments of hTERT dsRNA, mRNA and protein expression of hTERT and telomerase activity in A549 cells were suppressed, cell proliferation was markedly inhibited. Meanwhile, dsRNA didn't show unspecific toxic activity on A549 cells. CONCLUSIONS: hTERT dsRNA can specifically silent hTERT gene, inhibit telomerase activity and proliferation of A549 cells. hTERT dsRNA might be a potential method of gene therapy for lung cancer.

Adenocarcinoma↗
PubMed2005

[Influence of tangential excision within 24 postburn hours on the local wound inflammatory response in patients with deep partial thickness burn].

OBJECTIVE: To investigate the influence of early tangential excision within 24 postburn hours on local wound inflammatory response and tissue injury in patients with deep partial thickness burn. METHODS: Twelve patients with deep partial thickness burn were enrolled in the study. Tangential excision was performed within 24 postburn hours. The same wound of a patient was divided into three areas for harvesting tissue samples, i.e. pre-operation, post-operation and non-operation areas. For each patient, the biopsies from the pre-operation area were harvested before tangential excision, while those from post-operation and non-operation areas were harvested during 5 to 7 postburn days (PBDs). The contents of IL-8, MPO and MDA in wound tissue were determined by tissue culture and chemical colorimetry, respectively. HE and Mason's staining were employed to assess the degree of necrosis of the wound tissue. RESULTS: The IL-8, MPO and MDA contents in the local wound tissue after tangential excision were 6.83 +/- 1.85 microg/L, 4.07 +/- 0.87 U/g, and 8.94 +/- 5.66 micromol/g, respectively, which were significantly lower than those from non-operation area (P < 0.01). The inflammatory response in the non-operative wound area was distinct with expansion of necrotic tissue area. In contrast, the local inflammatory response of the wound after tangential excision was ameliorated without the enlargement of necrotic tissue area. CONCLUSION: Tangential excision within 24 postburn hours could be beneficial in ameliorating local inflammatory response, and in preventing progressive deepening of the burn wounds, thus it could accelerate wound healing in patients with deep partial thickness burn.

Adult↗
PubMed2005

[Establishment of a novel arrhythmia model in rats].

AIM: To establish a novel arrhythmia model in rats. METHODS: Coronary artery occlusion was produced in hyperlipidemic rats after the animals were fed a high fat and cholesterol chow for 15 days. The incidence, duration and score of arrhythmias were determined 1 hour after coronary occlusion. RESULTS: The incidence, duration and score of arrhythmia induced by coronary artery occlusion increased significantly in hyperlipidemic rats compared with those in normal rats (P < 0.05). In normal rats, pretreatment with amiodarone 60 mg x kg(-1) or verapamil 25 mg x kg(-1) 3 days before coronary artery occlusion did not influence the incidence, duration and score of arrhythmia (P > 0.05). In hyperlipidemic rats, amiodarone 60 mg x kg(-1) decreased the incidence, duration and score of arrhythmia (P < 0.05), but not verapamil 25 mg x kg(-1) (P > 0.05). CONCLUSION: The novel arrhythmia model induced by coronary artery occlusion in hyperlipidemic rats is reliable and similar to the pathophysiological state in human being.

Amiodarone↗
PubMed2004

Circadian rhythms of ethylene emission in Arabidopsis.

Ethylene controls multiple physiological processes in plants, including cell elongation. Consequently, ethylene synthesis is regulated by internal and external signals. We show that a light-entrained circadian clock regulates ethylene release from unstressed, wild-type Arabidopsis (Arabidopsis thaliana) seedlings, with a peak in the mid-subjective day. The circadian clock drives the expression of multiple ACC SYNTHASE genes, resulting in peak RNA levels at the phase of maximal ethylene synthesis. Ethylene production levels are tightly correlated with ACC SYNTHASE 8 steady-state transcript levels. The expression of this gene is controlled by light, by the circadian clock, and by negative feedback regulation through ethylene signaling. In addition, ethylene production is controlled by the TIMING OF CAB EXPRESSION 1 and CIRCADIAN CLOCK ASSOCIATED 1 genes, which are critical for all circadian rhythms yet tested in Arabidopsis. Mutation of ethylene signaling pathways did not alter the phase or period of circadian rhythms. Mutants with altered ethylene production or signaling also retained normal rhythmicity of leaf movement. We conclude that circadian rhythms of ethylene production are not critical for rhythmic growth.

Amino Acids, Cyclic↗
PubMed2004

Brassinosteroid signal transduction--choices of signals and receptors.

Small signaling molecules that mediate cell-cell communication are essential for developmental regulation in multicellular organisms. Among them are the steroids and peptide hormones that regulate growth in both plants and animals. In plants, brassinosteroids (BRs) are perceived by the cell surface receptor kinase BRI1, which is distinct from the animal steroid receptors. Identification of components of the BR signaling pathway has revealed similarities to other animal and plant signal transduction pathways. Recent studies demonstrated that tomato BRI1 (tBRI1) perceives both BR and the peptide hormone systemin, raising new questions about the molecular mechanism and evolution of receptor-ligand specificity.

Brassinosteroids↗
PubMed2004

[Inhibition of anti-sense human telomerase reverse transcriptase (hTERT) retroviral vector on lung cancer cells].

BACKGROUND & OBJECTIVE: Inhibition of telomere length can be achieved through suppression of telomerase activity, which may result in the inhibition of immortal cell proliferation. In order to explore the possibility of the telomerase as a target for lung cancer therapy, we investigated the effects of anti-sense human telomerase reverse transcriptase (hTERT) on telomerase activity and cell proliferation of A549 lung cancer cell line. METHODS: The anti-sense hTERT cDNA, an 835 bp in the 5' region of hTERT mRNA was amplified by reverse transcription polymerase chain reaction (RT-PCR), before cloning into pLXSN retroviral vector in sense and anti-sense orientations. A549 cells, a human lung cancer cell line, were infected with recombinant virus obtained after transfection into packaging cell PT67. The expression of hTERT protein was determined by Western blot analysis. The telomerase activity was measured by telomerase repeat amplification protocol (TRAP). The cell proliferation was depicted by cell morphology under inverted microscopy as well as cell growth curve. Apoptosis was analyzed by flow cytometry and DNA electrophoresis. RESULTS: Compared with sense hTERT transduction, hTERT expression and telomerase activity significantly decreased in A549 cells after anti-sense hTERT transduction. The cell proliferation was markedly inhibited with evidence of apoptosis. CONCLUSION: Anti-sense hTERT exhibited significant inhibition of telomerase activity and cell proliferation, in addition to acceleration of apoptosis. This implied the possibility of hTERT as the potential target for gene therapy of lung cancer.

Adenocarcinoma↗
PubMed2003

Detection of protein tyrosine-kinase (PTK) gene expression pattern in normal and malignant T lymphocytes by combined PTK-specific polymerase chain reaction and parallel denaturing gradient gel electrophoresis.

Protein tyrosine kinases (PTKs) control key functions of normal and malignant cells. Comparison of PTK gene expression among various cell populations may be achieved by amplification of the PTK cDNAs using degenerate primers which recognize two relatively invariable regions within their catalytic domain. This approach produces a mixture of PTK cDNA fragments with identical or very similar lengths which are difficult to separate by standard gel electrophoresis. These mixed products are then analyzed in a random fashion which leads to redundant cloning of some and potential omission of other PTKs. By using parallel denaturing gradient gel electrophoresis (DGGE) we have been able to separate the amplified PTK cDNAs derived from the same T-lymphocyte population and compare their expression between various types of normal and malignant T lymphocytes. One such PTK is the type I receptor for insulin-like growth factor, which we found to be preferentially expressed by neoplastic T cells on the both mRNA and protein levels. The combination of PCR which uses PTK-specific primers and parallel DGGE of the amplified PTK cDNAs may prove useful in studying mechanisms of cell activation and malignant transformation and in identifying targets for therapies based on selective inhibition of oncogenic PTKs.

Blotting, Northern↗
PubMed2002

The GSK3-like kinase BIN2 phosphorylates and destabilizes BZR1, a positive regulator of the brassinosteroid signaling pathway in Arabidopsis.

Brassinosteroids (BRs) are a class of steroid hormones essential for normal growth and development in plants. BR signaling involves the cell-surface receptor BRI1, the glycogen synthase kinase-3-like kinase BIN2 as a negative regulator, and nuclear proteins BZR1 and BZR2/BES1 as positive regulators. The interactions among these components remain unclear. Here we report that BRs induce dephosphorylation and accumulation of BZR1 protein. Experiments using a proteasome inhibitor, MG132, suggest that phosphorylation of BZR1 increases its degradation by the proteasome machinery. BIN2 directly interacts with BZR1 in yeast two-hybrid assays, phosphorylates BZR1 in vitro, and negatively regulates BZR1 protein accumulation in vivo. These results strongly suggest that BIN2 phosphorylates BZR1 and targets it for degradation and that BR signaling causes BZR1 dephosphorylation and accumulation by inhibiting BIN2 activity.

Arabidopsis↗
PubMed2002

Circadian rhythms confer a higher level of fitness to Arabidopsis plants.

Circadian rhythms have been demonstrated in organisms across the taxonomic spectrum. In view of their widespread occurrence, the adaptive significance of these rhythms is of interest. We have previously shown that constitutive expression of the CCA1 (CIRCADIAN CLOCK ASSOCIATED 1) gene in Arabidopsis plants (CCA1-ox) results in loss of circadian rhythmicity. Here, we demonstrate that these CCA1-ox plants retain the ability to respond to diurnal changes in light. Thus, transcript levels of several circadian-regulated genes, as well as CCA1 itself and the closely related LHY, oscillate robustly if CCA1-ox plants are grown under diurnal conditions. However, in contrast with wild-type plants in which transcript levels change in anticipation of the dark/light transitions, the CCA1-ox plants have lost the ability to anticipate this daily change in their environment. We have used CCA1-ox lines to examine the effects of loss of circadian regulation on the fitness of an organism. CCA1-ox plants flowered later, especially under long-day conditions, and were less viable under very short-day conditions than their wild-type counterparts. In addition, we demonstrate that two other circadian rhythm mutants, LHY-ox and elf3, have low-viability phenotypes. Our findings demonstrate the adaptive advantage of circadian rhythms in Arabidopsis.

Acclimatization↗
PubMed1996

A New Computer-imitated Model of Spatial Interaction between Interleukin-2 and Interleukin-2 Receptor Complex.

It is very meaningful to construct the spatial model of ligand-receptor interaction between interleukin-2 (IL-2) and interleukin-2 receptor (IL-2R) complex for the further studies in the structure-function relationship of IL-2 or IL-2R. In our study of the IL-2 molecule, we have found that Glu62 residue takes part in the binding to IL-2R alpha subunit and have confirmed that Glu126 residue in the residue bound to the IL-2R gamma subunit. In consideration with these discoveries and the progress in IL-2R subunits study, we have suggested a new model of the spatial interaction between IL-2 and IL-2R.

Journal Article↗
PubMed1996

The Influence of Amino Acid Substitutions on the Function of Interleukin-2.

The effects of some residues in IL-2 on its activity have been studied by site-directed mutagenesis. After changing 39 Met or 43 Lys to Pro, neither the CD spectra (s) nor the biological activities of these mutants were changed, implying that the 39 Met and 43 Lys were not involved in the reported alpha-helical structure. However after changing 52 Glu, 53 Leu or 54 Lys to Pro respectively the CD spectra were markedly changed and the activities were decreased significantly, showing that these three amino acids in IL-2 were integrated in the alpha-helix structure and very important for their biological functions. The significance of the above results was discussed.

Journal Article↗