Genomic analysis reveals phylogeny of Zygophyllales and mechanism for water retention of a succulent xerophyte.

Revealing the genetic basis for stress-resistant traits in extremophile plants will yield important information for crop improvement. Zygophyllum xanthoxylum, an extant species of the ancient Mediterranean, is a succulent xerophyte that can maintain a favorable water status under desert habitats; however, the genetic basis of this adaptive trait is poorly understood. Furthermore, the phylogenetic position of Zygophyllales, to which Z. xanthoxylum belongs, remains controversial. In this study, we sequenced and assembled the chromosome-level genome of Z. xanthoxylum. Phylogenetic analysis showed that Zygophyllales and Myrtales form a separated taxon as a sister to the clade comprising fabids and malvids, clarifying the phylogenetic position of Zygophyllales at whole-genome scale. Analysis of genomic and transcriptomic data revealed multiple critical mechanisms underlying the efficient osmotic adjustment using Na+ and K+ as "cheap" osmolytes that Z. xanthoxylum has evolved through the expansion and synchronized expression of genes encoding key transporters/channels and their regulators involved in Na+/K+ uptake, transport, and compartmentation. It is worth noting that ZxCNGC1;1 (cyclic nucleotide-gated channels) and ZxCNGC1;2 constituted a previously undiscovered energy-saving pathway for Na+ uptake. Meanwhile, the core genes involved in biosynthesis of cuticular wax also featured an expansion and upregulated expression, contributing to the water retention capacity of Z. xanthoxylum under desert environments. Overall, these findings boost the understanding of evolutionary relationships of eudicots, illustrate the unique water retention mechanism in the succulent xerophyte that is distinct from glycophyte, and thus provide valuable genetic resources for the improvement of stress tolerance in crops and insights into the remediation of sodic lands.

Physiological and transcriptomic analyses provide insight into thermotolerance in desert plant Zygophyllum xanthoxylum.

BACKGROUND: Heat stress has adverse effects on the growth and reproduction of plants. Zygophyllum xanthoxylum, a typical xerophyte, is a dominant species in the desert where summer temperatures are around 40 °C. However, the mechanism underlying the thermotolerance of Z. xanthoxylum remained unclear. RESULTS: Here, we characterized the acclimation of Z. xanthoxylum to heat using a combination of physiological measurements and transcriptional profiles under treatments at 40 °C and 45 °C, respectively. Strikingly, moderate high temperature (40 °C) led to an increase in photosynthetic capacity and superior plant performance, whereas severe high temperature (45 °C) was accompanied by reduced photosynthetic capacity and inhibited growth. Transcriptome profiling indicated that the differentially expressed genes (DEGs) were related to transcription factor activity, protein folding and photosynthesis under heat conditions. Furthermore, numerous genes encoding heat transcription shock factors (HSFs) and heat shock proteins (HSPs) were significantly up-regulated under heat treatments, which were correlated with thermotolerance of Z. xanthoxylum. Interestingly, the up-regulation of PSI and PSII genes and the down-regulation of chlorophyll catabolism genes likely contribute to improving plant performance of Z. xanthoxylum under moderate high temperature. CONCLUSIONS: We identified key genes associated with of thermotolerance and growth in Z. xanthoxylum, which provide significant insights into the regulatory mechanisms of thermotolerance and growth regulation in Z. xanthoxylum under high temperature conditions.

Massive increases in C31 alkane on Zygophyllum xanthoxylum leaves contribute to its excellent abiotic stress tolerance.

BACKGROUND AND AIMS: Desert plants possess excellent water-conservation capacities to survive in extreme environments. Cuticular wax plays a pivotal role in reducing water loss through plant aerial surfaces. However, the role of cuticular wax in water retention by desert plants is poorly understood. METHODS: We investigated leaf epidermal morphology and wax composition of five desert shrubs from north-west China and characterized the wax morphology and composition for the typical xerophyte Zygophyllum xanthoxylum under salt, drought and heat treatments. Moreover, we examined leaf water loss and chlorophyll leaching of Z. xanthoxylum and analysed their relationships with wax composition under the above treatments. KEY RESULTS: The leaf epidermis of Z. xanthoxylum was densely covered by cuticular wax, whereas the other four desert shrubs had trichomes or cuticular folds in addition to cuticular wax. The total amount of cuticular wax on leaves of Z. xanthoxylum and Ammopiptanthus mongolicus was significantly higher than that of the other three shrubs. Strikingly, C31 alkane, the most abundant component, composed >71 % of total alkanes in Z. xanthoxylum, which was higher than for the other four shrubs studied here. Salt, drought and heat treatments resulted in significant increases in the amount of cuticular wax. Of these treatments, the combined drought plus 45 °C treatment led to the largest increase (107 %) in the total amount of cuticular wax, attributable primarily to an increase of 122 % in C31 alkane. Moreover, the proportion of C31 alkane within total alkanes remained >75 % in all the above treatments. Notably, the water loss and chlorophyll leaching were reduced, which was negatively correlated with C31 alkane content. CONCLUSION: Zygophyllum xanthoxylum could serve as a model desert plant for study of the function of cuticular wax in water retention because of its relatively uncomplicated leaf surface and because it accumulates C31 alkane massively to reduce cuticular permeability and resist abiotic stressors.

[Clinical Significance of Platelet Closure Time in Patients with Multiple Myeloma].

OBJECTIVE: To explore the clinical significance of platelet closure time (PCT) in patients with multiple myeloma (MM). METHODS: Peripheral blood samples of 50 newly diagnosed MM patients treated in our hospital from July 2018 to November 2019 and 34 healthy persons underuent physical at the same time were collected. PCT induced by collagen/epinephrine (CEPI) and collagen/adenosinediphosphate (CADP) in peripheral blood were detected by PFA-200，and the clinical data included age, sex, leukocyte count, hemoglobin level, platelet count and level of serum creatinine, cystatin c, blood calcium, ß2-microglobulin (ß2-MG), bone marrow plasma cells, light chain protein, as well as the MM types, ISS stage of patients were collected. RESULTS: The level of PCT in MM patients was significantly higher than that in healthy persons; the level of PCT were significantly increased with the increasing of ISS stage in newly diagnosed MM patients; After chemotherapy with bortezomib/dexamethasone (BD), the level of PCT in 15 patients who were responded to the treatment was significantly lower than those before treatment. CONCLUSION: The platelet closure time is abnormal in MM patients, moreover, relates to the progress of the disease. It has an important clinical significance for the evaluation of diagnostic stage and therapeutic efficacy evaluation of MM patients.

[Expression of Versican and Its Related Molecules in Patient with Multiple Myeloma and Its Clinical Significance].

OBJECTIVE: To investigate the expression and clinical significant of VCAN and its related molecules in patients with MM. METHODS: Ficoll density gradient centrifugation method was used to speared the bone marrow mononuclear cell in 25 cases of MM before and after treatment, the relative mRNA expression of VCAN and their related molecules (FAK, FN, MK, and HAS) in bone marrow was detected by real-time quantitative PCR, and their protein expression was determined by Western bolt. RESULTS: The expression of VCAN, FK and FN in the effective group after treatment was significantly lower than that before treatment (P＜0.05), however, the expression of MK and HAS showed no statistically significantly different before and after treatment (P＜0.05). The expression of VCAN of patients in non remission group was significantly higher than that in control group (P＜0.05). The expression of FAK and FN of patients in no remission group was significant increased as compared with the patients in newly diagnosed group (P＜0.05). The relative expression of VCAN mRNA in the patients at 3rd stage was significantly higher than those at the 1st stage (P＜0.05) and control group but showed no significant difference to the patients at 2nd stage (P＜0.05). The expression of VCAN and its related proteins (FAK, MK, FN) showed positively correlation in bone marrow mononuclear cells of MM patients (P＜0.05). The correlation between VCAN and HAS was not statistically significant (r=0.259，P＞0.05). Survival analysis showed that the relative expression of VCAN mRNA was associated with OS (P=0.049) and PFS (P=0.041) in MM patients. CONCLUSION: VCAN and its related molecules are highly expressed in MM patients; VCAN may act as potential biomarker in the development of multiple myeloma.

[Curative Efficacy of Rituximab for ITP Patients with Different Sensitivity to Hormone].

OBJECTIVE: To investigatc the curative efficacy of low dose rituximab for glucocorticoid ineffective on dependent ITP patients and its relation with sensitivity to glucocorticoid so as to provide reference basis for rational use of drugs in clinical treatmant. METHODS: Seventy-ninth ITP patients enrolled in this study included the glucocorticoid-ineffective patients (19 cases) and glucocorticoid-dependent patients (60 cases). All ITP patients were treated with regimen consisted of high dose dexamethasone plus low dose rituximab (dexal-methasone 40 mg/d for 4 days per os, ritaximab 100 mg by intravenous infusion at D7, 14, 21 and 28 respectively). The patients after treatment were followed-up for 12 month, and the relation of patients sensitivity to glucocorticoid with therapentic response of rituximab was analyzed. The changes of Treg cell ratio and BAFF, IL-2 and sCD40L levels before and after treatment were detected by flow cytometry and ELISA respectively. RESULTS: The overall response rate (ORR) of patients treated with above- mentioned regemen at 1, 3, 6 and 12 months after treatment was 79.7% (63/79), 69.6% (55/79), 63.3% (50/79) and 60.8% (48/79) respectivcly, out of which the ORR of glucocorticoid ineffective and glucocorticoid-dependent ITP patients treated with above-mentioned regimen at 1, 3, 6 and 12 months after treatment was 47.4% (9/19) vs 90.0% (54/60), 36.8% (7/19) vs 80.0% (48/60), 21.1% (4/19) vs 76.7% (46/60), 21.1% (4/19) vs 73.3% (44/60), and the difference between 2 groups was statistically significant. The detection of T reg cell showed that the T reg cell ratio in glucocorticoid- ineffective and dependent patients at 1, 3, 6 and 12 months after treatment was (1.70±0.43)% vs (3.47±0.72)%, (1.66±0.33)% vs (4.29±0.91)%, (1.71±0.37)% vs (4.44±0.97)%, (3.36±0.54)% vs (4.29±1.04)%, respectively. The detection of cytokines showed that the levels of BAFF, IL-2 and sCD40L in plasma of glucocorticoid-dependent patients at 1 month after treatment significanlly decreased (P＜0.05), the levels of BAFF, IL-2 and sCD40L in plasma of glucocorticoid-ineffective patients although decreased at 1 mouth after treatment, but there was no statistical difference as compared with glucocosticoid-depenment patients. CONCLUSION: The treatment of glucocorticoid-dependent ITP patients with rituximab is more effective. The regulatory effect of rituximab on the T-reg cells, BAFF, IL-2 and sCD40L may be one of its mechanisms.

[Prognostic Significance of CD45dimCD117+ Cells in Patients with Acute Myeloid Leukemia after Complete Remission].

OBJECTIVE: To investigate the predictive value of CD45dimCD117+ phenotype-abnormal cells (hereinafter referred to as "abnormal cells") for relapse and prognosis in adult patients with acute myeloid leukemia (AML) within 2 weeks after the first complete remission (CR1). METHODS: The clinical data of patients with newly diagnosed AML (non-acute promyelocytic leukemia) admitted in our department from July 1, 2014 to June 30, 2017 were analyzed retrospectively, and the relationship between clinical features at the initial diagnosis and the abnormal phenotype cells of CD45dimCD117+ within 2 weeks after CR1 with the prognosis were analyzed. RESULTS: A total of 91 patients with CD45dimCD117+ abnormal cells were detected. The median age was 51 years old, the median WBC count was 11.60×109/L, and the median ratio of bone marrow blast cells was 0.35 at initial diagnosis. According to the FAB classification, 1 (1.1%), 7 (7.7%), 38 (41.7%), 20 (22.0%), 21 (23.1%) and 4 (4.4%) patients were classifice as M0, M1, M2, M4, M5, and M6, respectively. According to the NCCN risk stratification, 30 (33.0%), 51 (56.0%), and 10 (11.0%) patients were determined as good, moderate, and poor prognosis, respectively. The median ratio of abnormal cells within 2 weeks after CR1 was 1.8500 (0.0236-8.0000)%. The median time from initiation of induction therapy to the acquisition of CR was 46 days, median recurrence-free survival time was 319 days, and median overall survival time was 352 days. A total of 45 patients relapsed, of which 14 died; 46 patients did not relapse, of which 3 died. The cutoff of abnormal cells by receiver operating characteristic curve (ROC) analysis was 2.055% (Se=0.733，Sp=0.761). The abnormal cell ratio was＞2.055% in 44 patients, the median ratio of abnormal cells was 3.075%, among which 33 patients relapsed and 12 patients died; the abnormal cell ratio was ＜2.055% in 47 patients, the median ratio of abnormal cells was 1.150%, 12 patients relapsed and 5 patients died. Regression analysis showed that WBC count＞50×109/L and abnormal cell ratio＞2.055% were independent risk factors for recurrence. The abnormal cell ratio＞2.055% group had a 2-year RFS rate of 54.3% and a 2-year OS rate of 52.8%. The abnormal cell ratio＜2.055% group had a 2-year RFS rate of 86.6% (P=0.018), and a 2-year OS rate of 85.3% (P＜0.05). CONCLUSION: For adult AML patients, CD45dimCD117+ phenotypical abnormal cells ratio＞2.055% within 2 weeks after CR1 is an independent risk factor for recurrence, which also is an dverse factor for RFS and OS.

[Risk Factors and Prognosis of Hepatic cGVHD after Allogeneic Hematopoietic Stem Cell Transplantation].

OBJECTIVE: To analyze the risk factors and prognosis of hepatic chronic GVHD after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: The clinical data of 147 patients undergoing allo-HSCT from January 2013 to December 2016 were analyzed, the correlation between recipient age and sex, disease state, matched degree of HLA, donor sex, stem cell sources, ATG in GVHD prophylaxis, liver dysfunction during conditioning period, pre-transplant HBsAg, prior aGVHD and hepatic cGVHD were studied, and the correlation between hepatic cGVHD and prognosis were analysed. RESULTS: Thirty-two patients had hepatic cGVHD, cumulative incidence of 26.4%. In univariate analysis, pre-transplant HBsAg+and liver dysfunction during conditioning period were not significantly related with hepatic cGVHD (P>0.05). In multivariate analysis, prior acute GVHD (HR=2.087, P=0.045) was the independent risk factor for hepatic cGVHD, ATG (HR=0.231, P=0.000) was significantly related with a lower incidence of hepatic cGVHD. In univariate analysis, patients with hepatic cGVHD had a lower 2 years relapse rate (P=0.038). CONCLUSION: Prior acute GVHD is the independent risk factor for hepatic cGVHD, the ATG can significantly reduce the incidence of hepatic cGVHD. Hepatic cGVHD has been found to relate with a lower 2 years relapse rate.

[Effect of Interfering the ADAM10 by Lentivirul Vector-Mediated shRNA on Multiple Myeloma MM.1S Cell Proliferation].

OBJECTIVE: To explore the effect of interfering ADAM10 on proliferation and apoptosis of multiple myeloma MM.1S cells, and its possible mechanism. METHODS: Four pairs of shRNA-coding sequences directed against different sites of ADAM10 mRNA were designed and inserted into lentiviral vector plasimd pLVshRNA-EGFP(2A) Puro for constructing the sh/ADAM10-1, sh/ADAM10-2, sh/ADAM10-3, sh/ADAM10-4 and sh/Con. These plasmids and lentiviral packaging plasmids were co-transfected into the packaging cells 293FT, then the virus particles were collected and the viral titer was assayed after concentration, and these viral particles were transfected to MM.1S cells. The flow cytometry was used to sort GFP+ cells. Real-time quantitative PCR, and Western blot were used to detect the effect of interfering the ADAM10 gene by lentiviral vector mediated shRNA. The proliferation-inhibition curve was plotted by CCK-8 method, the cell viability and apoptosis were detected by flow cytometry with Annexin V and 7-AAD staining, the transcripts of pro-apoptosis gene BAD, BAK, BIK, anti-apoptotic genes BCL-2, c-Myc and Notch1 target gene Hes-1 were detected by real-time PCR. RESULTS: Lentivirus vector was successfully constructed, that could specifically interfere ADAM10 expression. Interfering ADAM10 gene could inhibit the MM.1S cell proliferation and induce apoptosis. After the interferencing ADAM10 gene the mRNA levels of pro-apoptosis gene BAD, BAK and BIK were increased, and the mRNA levels of anti-apoptotic genes BCL-2 and c-Myc were reduced. Q-PCR results showed that the mRNA level of Notch1 were increased, but that of Hes-1 were reduced. CONCLUSION: Down-regulated ADAM10 expression can significantly inhibit multiple myeloma MM.1S cell proliferation and promote the apotosis. Its mechanism may be related to Notch1 signaling pathways.

[Effect of ADAM10 Inhibitor GI254023X on Proliferation and Apoptosis of Multiple Myeloma H929 Cells and Its Possible Mechanisms].

OBJECTIVE: To investigate the effect of ADAM10 inhibitor GI254023X on the proliferation and apoptosis of multiple myeloma H929 cell line and its mechanisms. METHODS: H929 cells were treated with different concentrations of GI254023X, the proliferation-inhibitive curve was assayed and plotted by CCK-8 method, the cell viability and apoptosis were detected by flow cytometry with Annexin V/7-AAD double staining. The cleavage of Notch1 protein (cleaved notch1) was determined by Western blot. The transcripts of Notch1 target gene Hes-1 were detected by real-time PCR. RESULTS: The GI254023X inhibited the proliferation of H929 cells in the time- and dose- dependent manners. As compared with the control group, the apoptosis of cells increased along with enhancement of GI254023X concentration; The expression of cleaved Notch1 was down-regulated after the treatment with GI254023X. The levels of Hes-1 mRNA transcripts in H929 cells was reduced in GI254023X treated group. CONCLUSION: GI254023X can remarkably inhibit the proliferation and induce the apoptosis of H929 cells. Its mechanism may be associated with inbihition of Notch1 activation.

[Blockage of Th17 cells differentiation exacerbated mouse acute intestine graft-versus-host disease following allogeneic bone marrow transplantation].

OBJECTIVE: To study the role of Th17 cells in acute intestine graft-versus-host disease following allogenetic bone marrow transplantation(allo-BMT). METHODS: Mice were split randomly into five groups: normal control, irradiated, allo-BMT, allo-BMT + DMSO and allo-BMT + Halofuginone (HF) groups. HF was given intraperitoneally at a dose of 5 µg per mouse from -1 d to 10 d after allo-BMT. aGVHD symptoms were followed-up to perform clinical and pathogenic scores. The levels of Th1/Th17, interleukin-17 and interferon-γ were measured by flow cytometry at day 7 d. mRNA expressions of T-bet, RORγT, CXCL9, CXCL10, CXCL11 and CCL20 in intestine were evaluated by real-time PCR. RESULTS: Intestinal damages in allo-BMT-HF mice was more serious than in normal control and allo-BMT groups at day 14 after transplantation. At day 7, Th17 ratio in allo-BMT + HF group was significantly lower than in allo-BMT group. IL-17A was not detected, but Th1 ratio was higher in allo-BMT + HF. There was a similar increment in the relative expressions of T-bet in both allo-BMT and allo-BMT + HF groups. Expressions of CXCL9 and CXCL10 elevated in allo-BMT + HF group, which were significantly higher than those in allo-BMT group (P < 0.01). CCL20 expression significantly increased in allo-BMT group, but it was not detected in allo-BMT + HF group. CONCLUSION: Blockage of th17 cells differentiation exacerbated acute intestine graft versus-host disease.