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Qi Zou

Publications and source records attributed to Qi Zou.

8 recordsLinked to original sources

soFusion: facilitating tissue structure identification via spatial multi-omics data fusion.

The rapid advancement of spatial multi-omics technologies has opened new avenues for dissecting tissue architecture with unprecedented resolution. However, inherent disparities across omics modalities, such as differences in biological hierarchy and resolution, pose significant challenges for integrative analysis. To address this, we present soFusion, a method for representation learning on spatial multi-omics data that enables automated identification of tissue compartmentalization. soFusion employs a graph convolutional network (GCN) to extract latent embeddings from spatial omics profiles. To simultaneously capture both cross-modality relationships and modality-specific features, we introduce a novel strategy for intra- and inter-omics feature learning. Moreover, modality-specific decoders are designed to preserve the unique information embedded in each omics type. We evaluated soFusion on multiple datasets including gene expression, protein expression, and epigenetic features. Across all benchmarks, soFusion consistently outperformed existing methods in delineating anatomical structures and identifying spatial domains with improved continuity and reduced noise. Collectively, soFusion offers an effective solution for spatial multi-omics integration, substantially enhancing the robustness of spatial domain identification.

Humans↗

Alleviation of photoinhibition in drought-stressed wheat (Triticum aestivum) by foliar-applied glycinebetaine.

Effects of foliar application of 100 mmol/L glycinebetaine (GB) on PS II photochemistry in wheat (Triticum aestivum) flag leaves under drought stress combined with high irradiance were investigated. The results show that GB-treated plants maintained a higher net photosynthetic rate during drought stress than non-GB treated plants. Exogenous GB can preserve the photochemical activity of PSII, for GB-treated plants maintain higher maximal photochemistry efficiency of PSII (F(v)/F(m)) and recover more rapidly from photoinhibition. In addition, GB-treated plants can maintain higher anti-oxidative enzyme activities and suffer less oxidative stress. Our data suggest that GB may protect the PSII complex from damage through accelerating D1 protein turnover and maintaining anti-oxidative enzyme activities at higher level to alleviate photodamage. Diethyldithiocarbamate as well as streptomycin treatment can impair the protective effect of GB on PSII. In summary, GB can enhance the photoinhibition tolerance of PSII.

Antioxidants↗

[Effects of root-applied glycinebetaine on the composition and function of wheat thylakoid membrane under drought stress].

Two wheat cultivars (Triticum aestivum L.), HF9703 tolerant to drought and SN215953 sensitive to drought, were used to study the effects of glycinebetaine on the composition and function of thylakoid membrane. The wheat seedlings with two leaves were pretreated with Hoagland solution containing 1.5 mmol/L glycinebetaine (GB) for 72 h, then cultured with Hoagland solution containing 15% PEG-6000 for 48 h. The seedling leaves were used for mensuration. The results indicated that the chlorophyll, monogalactosyl diaylglycerol (MGDG), digalactosyl diacylglycerol (DGDG) and phosphatidylglycerol (PG) contents of the two wheat cultivars decreased significantly (P<0.05) under drought stress. GB alleviated their decrease. The sulfoquinovosyl diacylglycerol (SQDG) content, trans-hexadecenoic [16:1(3t)] and saturated fatty acid content of MGDG in HF9703 increased significantly (P<0.05), while in SN215953, the sulfoquinovosyl diacylglycerol (SQDG) and trans-hexadecenoic [16:1(3t)] contents decreased significantly under drought stress, but the saturated fatty acid content of MGDG increased slightly. These differences between the two wheat cultivars might account for much of the difference in drought tolerance between them. Ca2+-ATPase activity of thylakoid membrane, Hill-reaction activity and photosynthesis were decreased markedly (P<0.05) by drought stress. GB ameliorated these effects on thylakoid membrane, and the effect of GB on SN215953 was stronger than on HF9703. Discussion was made on the possible mechanism of the alleviating effect of root-applied GB on the composition and function of thylakoid membrane.

Betaine↗

The function of chloroplastic NAD(P)H dehydrogenase in tobacco during chilling stress under low irradiance.

The function of chloroplastic NAD(P)H dehydrogenase (NDH) was examined by comparing a tobacco transformant (DeltandhB) in which the ndhB gene had been disrupted with its wild type, upon exposure to chilling temperature (4 degrees C) under low irradiance (100 micro mol m(-2) s(-1) PFD). During the chilling stress, the maximum photochemical efficiency of PSII (F(v)/F(m)) decreased markedly in both the wild type and DeltandhB. However, both F(v)/F(m) and P700(+), as well as the PSII-driven electron transport rate (ETR), in DeltandhB were lower than that in the wild type, implying that NDH-dependent cyclic electron flow around PSI functioned to protect the photosynthetic apparatus from chilling stress under low irradiance. Under the stress, non-photochemical quenching (NPQ), particularly the fast relaxing NPQ component (qf) and the de-epoxidized ratio of the xanthophyll cycle pigments, (A+Z)/(V+A+Z), were distinguishable in DeltandhB from those in the wild type. The lower NPQ in DeltandhB might be related to an inefficient proton gradient across thylakoid membranes (DeltapH) because of lacking an NDH-dependent cyclic electron flow around PSI at chilling temperature under low irradiance.

Chlorophyll↗

[Effect of heat hardening on allocation of excitation energy in Brassica oleracea seedling leaves].

In this paper, Brassica oleracea was used to investigate the effect of heat hardening (HH) on its photosynthetic characteristics and chlorophyll fluorescence parameters. No distinct changes were observed in the variable fluorescence (Fv), photochemical quenching coefficient (qP), non-photochemical quenching coefficient (qN), and quantum yield of PS II electron transport (phiPS II) between HH treatment and control when the leaf temperature was 25-35 degrees C. When the leaf temperature was higher than 35 degrees C, there were obvious differences in the levels of Fv, qP, phiPS II and qN between HH treatment and control. For example, at 37 degrees C, the Fv, qP and phiPS II in HH treatment were 53%, 24%, and 86% higher than those in control, respectively, but the qN was 22% lower. The photoinhibitory quenching (qNs) in HH treatment was significantly decreased. The results showed that 'high energy' quenching (qNf) was an important photoprotection mechanism that effectively dissipated the excess excitation energy, protected the PS II reaction center complexes from photodamage, and increased the ability of resisting photoinhibition, which were consistent with high photosynthesis rates.

Brassica↗

[Photosynthetic characteristics and photoprotective mechanisms during leaf development of soybean plants grown in the field].

Gas exchange, chlorophyll a fluorescence and HPLC analysis were used to explore photosynthesis and dissipation of excited energy in soybean leaves from emergence to full development. During leaf development, both photosynthetic rate and stomata conductance increased gradually, whereas the increase in stomata conductance significantly lagged behind that of photosynthetic rate. Considering stomatal limiting value, it can be easily deduced that photosynthesis was considerably limited by low stomatal conductance during leaf development. Though the maximum quantum yield of photosystem II (PSII) photochemistry (F(v)/F(m)) was quite high at the stages of leaf development, it is appreciably lower than that in fully developed leaves. Reversible decrease in F(v)/F(m) occurred caused by high irradiance during daily courses at all stages of leaf development, indicating that no severe photoinhibition occurred when exposed to high light. Under high irradiance, a substantial increase in the actual PSII efficiency (Phi(PSII)) together with a marked decreased in non-photochemical quenching (NPQ) occurred during the process of leaf development. Compared with the values obtained at 9:00 AM, Phi(PSII) in developing leaves was drastically down-regulated after midday, whereas NPQ was enhanced significantly. Compared with fully expanded leaves, those developing leaves, with higher xanthophyll pool size, exhibited a much higher ratio of zeaxanthin (Z) + antheraxanthin (A) to Chl under irradiation. In addition, the relative xanthophyll pool size (V+A+Z)/Chl was found to decrease with leaf development. Our experiments revealed that the decline of xanthophyll cycle pool during leaf development was due to the fact that the chlorophyll content increased faster than the xanthophyll cycle pigment content. We suggest that as soon as leaf emerged, photoprotective mechanism was developed preferentially which can effectively protect leaves against excessive irradiance. Thermal dissipation depending on xanthophyll cycle is a very important photoprotective mechanism for dealing with high irradiance during leaf development.

Chlorophyll↗

[Effects of chitosan treatment on physiological and biochemical characteristics in cucumber seedlings under low temperature].

Chitosan 50 mg/L treatment alleviated the low temperature injury of cucumber seedling membrane. The chitosan treatment reduced electrolyte leakage and the MDA content of cucumber leaves and alleviated the decreases in photosynthetic rate, the photochemical efficiency of photosystem II (PhiPSII), the photochemical quenching of fluorescence (q(P)) and the efficiency of excitation energy captured by the open photosystem II reaction centers (F(v)'/F(m)') under low temperature (6 degrees C). At the same time, the chitosan treatment enhanced the antioxidant enzymatic activities and increased the proline and soluble protein contents in cucumber leaves under low temperature. The results indicated that chitosan treatment improved cold resistance of cucumber seedlings,which protected the membrane system, improved the capability of eliminating active oxygen species and alleviated the damage to photosynthetic organization under low temperature.

Catalase↗

[Effects of soil water stress and shading on growth characteristics of ginger].

Water stress decreased the chlorophyll contents, stomatic density, and stomatic size of ginger leaves, and reduced the root activity and magnitude of bleeding sap of ginger roots. Under the same water contents, shading increased the root activity and the chlorophyll contents and stomatic size of upper cuticulae of ginger leaves, but decreased the stomatic density and size of their lower cuticulae. Water stress influenced the growth and yield of ginger significantly, but the effects of light intensity on ginger growth and yield were different under different water contents. Under normal water content, ginger grew better and yield was higher in natural sunlight, while under water stress, ginger grew better and yield was higher in shading.

Chlorophyll↗