Search PubMed⌕ Search

Biomedical subjects

Xiaoli Sun

Publications and source records attributed to Xiaoli Sun.

10 recordsLinked to original sources

Genome-Wide Identification of the Soybean GH5 Gene Family and Functional Analysis of GmGH5-22 in Salt Tolerance.

Plant GH5 family genes function in both cell wall biosynthesis and stress responses. However, comprehensive studies on GH5 genes in the soybean remain limited. Here, we identified 28 GmGH5 genes from the soybean genome. Phylogenetic analysis assigned these genes to three subfamilies (I-III), with no representatives in subfamily IV. The GmGH5 family harbors 15 conserved motifs, which are largely similar within subfamilies but differ across subfamilies. Additionally, exon-intron structures (2-7 introns) exhibit clade-specific patterns, with members within the same clade sharing similar intron numbers and lengths, whereas distinct clades show some variation. The promoter regions of GmGH5 genes contained various cis-acting regulatory elements associated with stress responses and developmental processes. Transcriptome-based expression profiling revealed distinct tissue-specific expression patterns of GmGH5 genes. RT-qPCR further confirmed their differential expression under salt, alkaline, cold, and drought stresses, especially a significant increase in GmGH5-22 expression under salt stress (approximately 22-fold at 6 h, **** p < 0.0001). Furthermore, GmGH5-22 was highly expressed in roots, and transient expression in tobacco leaves showed its peripheral localization, which aligns with its predicted extracellular localization, suggesting that GmGH5-22 is highly likely localized to the cell wall. Overexpression of GmGH5-22 in soybean hairy roots significantly improved tolerance to salt stress. These findings establish a foundation for functional characterization of GmGH5 genes and provide viable targets for molecular breeding to enhance salt tolerance in soybeans.

GH5 family↗

T2T Genome Assembly and Multi-Omics Data Reveal Terrestrial Adaptation and Mucus Biosynthesis in Tropical Leatherleaf Slug (Laevicaulis alte).

Laevichaulis alte is a slug in the order Systellommatophora that evolved from aquatic ancestors and now faces strong challenges from desiccation, respiration on land, and novel pathogens. Its mucus is essential for water retention, locomotion, and defense. To link terrestrial adaptation with mucus biosynthesis, we generated a gap-free genome assembly of L. alte using PacBio HiFi reads, Oxford Nanopore ultra-long reads, and Hi-C data. The genome shows low heterozygosity and holocentromeric chromosomes. Functional metabolomics revealed marked metabolic shifts between L. alte and the closely related aquatic species Peronia verruculata. In L. alte, differential metabolites were enriched in lipid metabolism, immune regulation, and stress response pathways, consistent with life in a dry and microbe-rich terrestrial environment. Comparative genomics and transcriptomics identified candidate genes linked to mucus secretion and physiological adaptation, including VEGF, ASGR2, and COL6A6. Further analyses highlighted the vascular endothelial growth factor (VEGF) gene family as a key regulator connecting angiogenesis, tissue remodeling, and mucus production pathways in L. alte. Together, this gap-free genome and multi-omics dataset establish a molecular framework that links genomic innovation, mucus biology, and terrestrial adaptation in Systellommatophora, and they offer a basis for understanding ecological niche specialization in land molluscs.

Animals↗

Blockage of epidermal growth factor receptor by quinazoline tyrosine kinase inhibitors suppresses growth of human hepatocellular carcinoma.

Epidermal growth factor receptor (EGFR) is highly expressed in many human tumors including hepatocellular carcinoma (HCC). Therefore, inhibition of EGF receptors could be a potential target for anticancer therapy. In this study, we investigated the effects of two EGFR tyrosine kinase inhibitors, PD153035 and its analogue 4-[[3-chloro-4-fluorophenyl]amino]-6,7-dimethoxyquinazoline hydrochloride (ANAPD) on human HCC cell lines by cell proliferation assay, flow cytometry and Western blot. Our results demonstrated that both EGFR inhibitors inhibited tumor cell growth in a dose-dependent manner, but ANAPD was more potent than PD153035. These specific inhibitors not only blocked EGF-stimulated EGFR autophosphorylation but also targeted EGFR signaling including MAPK and Akt pathways. Furthermore, EGFR inhibitors induced a delay in cell cycle progression and a G(1) arrest together with a partial G(2)/M block. EGFR inhibitors also induced tumor cells to undergo apoptosis. In conclusion, this study demonstrated that both PD153035 and ANAPD inhibit tumor cell growth in HCC through inhibition of EGFR signaling pathway, and ANAPD is a more potent inhibitor than PD153035. This suggested that blockage of EGF receptors may provide an effective therapeutic approach for human HCC and ANAPD could be a potential drug candidate for the treatment of HCC.

Apoptosis↗

Mars 1064 nm spectral radiance measurements determined from the receiver noise response of the Mars Orbiter Laser Altimeter.

A technique was developed to compute the radiance of the scene viewed by the optical receiver of the Mars Orbiter Laser Altimeter. The technique used the detection threshold and the false detection rate of the receiver to provide a passive radiometry measurement of Mars at the 1064 nm wavelength over a 2 nm bandwidth and subkilometer spatial resolution in addition to the altimetry and active radiometry measurements. The passive radiometry measurement is shown to have a 2% or better precision and has been stable over several Martian years. We describe the principle of operation of the instrument and its calibration and assess its performance from sample orbital measurements.

Journal Article↗

Enantiomeric separation of synthetic 2,3-dihydroxy-3-phenylpropionate compounds by beta-cyclodextrin-modified capillary electrophoresis.

A new capillary electrophoretic method was developed for enantiomeric separation and optical impurity analysis of three synthetic 2,3-dihydroxy-3-phenylpropionate compounds using native beta-cyclodextrin (beta-CD) as chiral selector and borate as a background electrolyte. The separation was carried out in uncoated capillary (58.5 cm x 75 microm I.D., effective length 48.5 cm). The results showed that beta-CD as the chiral selector exhibited good enantioselectivity and the baseline separation was obtained at pH 9.8, 200 mM borate buffer containing 1.7% beta-CD at applied voltage 15 kV and capillary temperature 20 degrees C within 15 min. The precision of each tested compound was less than 1.0% at migration time and 5.0% in corrected peak area and the accuracy of the method was in the range of 98.7-105%. Furthermore, the developed method was successfully applied to the determination of the undesirable trace (2S,3R)-(+)-form impurity in the synthetic (2R,3S)-(-)-2,3-dihydroxy-3-phenylpropionate samples.

Buffers↗

Two-way laser link over interplanetary distance.

Here we report timed observations with subnanosecond precision of short laser pulses at a distance of nearly 24 million kilometers between the Mercury Laser Altimeter (MLA) aboard the MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft and the NASA Goddard Geophysical and Astronomical Observatory (GGAO). Forty MLA downlink observations and 90 uplink observations were obtained during observing sessions on 27 and 31 May 2005. Precise standard ground timing allowed a solution for spacecraft range, range rate, and acceleration, as well as clock bias. This experiment established a new distance record for laser detection and accomplished a two-way laser link at an interplanetary distance.

Journal Article↗

Chiral separation of synthetic vicinal diol compounds by capillary zone electrophoresis with borate buffer and beta-cyclodextrin as buffer additive.

The investigation on capillary electrophoretic enantioseparation of six synthetic compounds containing vicinal diol groups has been undertaken to acquire the optimum conditions using native beta-cyclodextrin (beta-CD) as chiral selector and borate as a background electrolyte. The separation was carried out in an uncoated capillary (58.5 cm x 75 microm i.d., effective length 48.5 cm) and the effects of several important factors were investigated in detail. The results showed that beta-CD as a chiral selector exhibited good enantioselectivity and that the enantioseparation was greatly influenced by the structure of the diols, the borate concentration and the buffer pH. The optimum performance was obtained for the chiral vicinal diols under the conditions of 200 mM borate buffer of pH 9.8 containing 1.7% beta-CD at an applied voltage of 15 kV and a capillary temperature of 20 degrees C. Under the conditions, four diols were baseline separated with fast analysis time and the good theoretical plate numbers (above 10 x 10(4)) and favorable migration-time reproducibilities (RSDs below 3.0%) were obtained. The separation results were satisfactory.

Borates↗

Cyclical regulation of the exocyst and cell polarity determinants for polarized cell growth.

Polarized exocytosis is important for morphogenesis and cell growth. The exocyst is a multiprotein complex implicated in tethering secretory vesicles at specific sites of the plasma membrane for exocytosis. In the budding yeast, the exocyst is localized to sites of bud emergence or the tips of small daughter cells, where it mediates secretion and cell surface expansion. To understand how exocytosis is spatially controlled, we systematically analyzed the localization of Sec15p, a member of the exocyst complex and downstream effector of the rab protein Sec4p, in various mutants. We found that the polarized localization of Sec15p relies on functional upstream membrane traffic, activated rab protein Sec4p, and its guanine exchange factor Sec2p. The initial targeting of both Sec4p and Sec15p to the bud tip depends on polarized actin cable. However, different recycling mechanisms for rab and Sec15p may account for the different kinetics of polarization for these two proteins. We also found that Sec3p and Sec15p, though both members of the exocyst complex, rely on distinctive targeting mechanisms for their localization. The assembly of the exocyst may integrate various cellular signals to ensure that exocytosis is tightly controlled. Key regulators of cell polarity such as Cdc42p are important for the recruitment of the exocyst to the budding site. Conversely, we found that the proper localization of these cell polarity regulators themselves also requires a functional exocytosis pathway. We further report that Bem1p, a protein essential for the recruitment of signaling molecules for the establishment of cell polarity, interacts with the exocyst complex. We propose that a cyclical regulatory network contributes to the establishment and maintenance of polarized cell growth in yeast.

Actins↗

[Studies on chemical constituents in essential oil from wild Atractylodes lancea in dabie mountains].

The chemical constituents in essential oil of wild Atractylodes lancea (Thumb.) DC. from Dabie Mountains were studied. The essential oil was extracted by simultaneous distillation and extraction equipment and analyzed by gas chromatography-mass spectrometry method. 49 compounds were identified and they represent 92.49% of the total peak aeras. The extraction method and solvent selection of the essential oil were studied. The oil yields and major constituents from Atractylodes lancea (Thumb.) DC. from Dabie Mountains were contrasted to that had been reported. The results showed that Atractylodes lancea (Thumb.) DC. from Dabie Mountains had more essential oil (10.14%) and there were more constituents in it. The main constituents in the essential oil were hinesol, beta-eudesmol, 1H-cyclopropa (a) naphthalene, 1a,2,3,5,6,7,7a,7b-octaphdro-1,1,7,7a-tetramethyl-, [1aR-(1a. alpha, 7. alpha, 7a. alpha,7b. alpha-)] -and gamma-eudesmol. Both the major constituents and contents were different from that had been reported.

Alkanes↗

[Portosystemic shunt via the left branch of portal vein for the prevention of encephalopathy following transjugular intrahepatic portosystemic shunt].

OBJECTIVE: To determine and analyze plasma ammonia concentration difference of the portal vein system and ramifications of rabbits and consequently guide selection of the portal vein in transjugular intrahepatic portosystemic shunt (TIPS) so that reduce shunt-induced hepatic encephalopathic incidence. To evaluate clinical significance of transjugular intrahepatic left branch of portal vein portosystemic shunt (TILPS) and to analyse hemodynamics of both branches of the portal vein and to observe long-term results in the prevention of encephalopathy. METHODS: Blood samples in different portal vein branches of rabbits were collected and the plasma ammonia concentration was assayed and compared. The left branch of portal vein was used as the puncture site to perform TILPS and to keep away from the right branch of portal vein blood that contains nutrition and toxin. RESULTS: Plasma ammonia content was superior in the mesenteric vein and higher than the portal vein branch, the splenic vein, and the vena cava. The right portal vein was above the left. Encephalopathy did not occur in all patients within 3 months. Of the 341 patients undergoing TILPS, encephalopathy occurred in only 5 patients (1.47%) and shunt abnormalities in 19 patients (5.57%) verified by venography during overall follow-up period. CONCLUSIONS: Selective left branch of the portal vein portosystemic shunt can decrease encephalopathy obviously and protect liver function.

Adult↗