Genome-wide identification of the expansin gene family reveals that expansin genes are involved in fibre cell growth in cotton.

BACKGROUND: Expansins (EXPs), a group of proteins that loosen plant cell walls and cellulosic materials, are involved in regulating cell growth and diverse developmental processes in plants. However, the biological functions of this gene family in cotton are still unknown. RESULTS: In this paper, we identified a total of 93 expansin genes in Gossypium hirsutum. These genes were classified into four subfamilies, including 67 GhEXPAs, 8 GhEXPBs, 6 GhEXLAs, and 12 GhEXLBs, and divided into 15 subgroups. The 93 expansin genes are distributed over 24 chromosomes, excluding Ghir_A02 and Ghir_D06. All GhEXP genes contain multiple exons, and each GhEXP protein has multiple conserved motifs. Transcript profiling and qPCR analysis revealed that the expansin genes have distinct expression patterns among different stages of cotton fibre development. Among them, 3 genes (GhEXPA4o, GhEXPA1A, and GhEXPA8h) were highly expressed in the initiation stage, 9 genes (GhEXPA4a, GhEXPA13a, GhEXPA4f, GhEXPA4q, GhEXPA8f, GhEXPA2, GhEXPA8g, GhEXPA8a, and GhEXPA4n) had high expression during the fast elongation stage, and GhEXLA1c and GhEXLA1f were preferentially expressed in the transition stage of fibre development. CONCLUSIONS: Our results provide a solid basis for further elucidation of the biological functions of expansin genes in relation to cotton fibre development and valuable genetic resources for future crop improvement.

Aromatase inhibitor letrozole in synergy with curcumin in the inhibition of xenografted endometrial carcinoma growth.

OBJECTIVE: Endometrial carcinoma is a malignant tumor in the uterus. Its current treatment is not satisfactory. The present study aimed to promote the inhibitory effect on the implanted endometrial tumor growth. METHODS: Nude mice were implanted with endometrial carcinoma. Some tumor-laden mice were treated with aromatase inhibitor letrozole and/or curcumin. The tumor growth was monitored. Tumor cell apoptosis was detected in both control and treated groups. RESULTS: Fifty mice were successfully implanted with the endometrial tumor. Treatment with letrozole markedly inhibited the tumor growth; the inhibitor effect was further strengthened by combination with letrozole and curcumin. The results also showed that letrozole enhanced the expression of Bax and cytochrome c release and suppressed the expression of estrogen receptor in tumor cells. Treatment with curcumin inhibited the expression of Bcl-2 in tumor cells at the mRNA and protein levels. Tumor cell apoptosis was observed in mice treated with either letrozole or curcumin; however, combination of letrozole and curcumin further enhanced the inhibitory rate in tumor growth. CONCLUSIONS: Treatment with either letrozole or curcumin could inhibit the xenografted endometrial tumor growth via inducing apoptosis in tumor cells. Combination of letrozole and curcumin further strengthened the inhibitory effect on tumor growth.

Chemical constituents from the rhizomes of Polygonatum sibiricum Red. and anti-inflammatory activity in RAW264.7 macrophage cells.

Chemical investigation of the rhizomes of Polygonatum sibiricum Red. led to the identification of 27 constituents. Among them, a total of 16 compounds were obtained from Polygonatum for the first time, in which, 3 and 4 were also firstly isolated as natural products. Anti-inflammatory activity studies on 13 isolated compounds showed that ß-carboline constituents, especially compounds 1 and 2, significantly inhibited the expression of NO, TNF-α, IL-6 and IL-1ß in lipopolysaccharide (LPS)-treated RAW264.7 macrophage cells. Moreover, western blotting analysis demonstrated that compound 1 significantly inhibited the expression of COX-2, iNOS and the activation of NF-κB, suggesting that ß-carboline structures may play an important role in inhibition of NF-κB signaling pathway, which thereby inhibits the production of inflammatory factors. The present research may not only help further elucidation of the anti-inflammatory mechanism of P. sibiricum Red., but also provide the potential bioactive molecules for inflammatory diseases research.

[Export of Total Organic Carbon (TOC) from Karst Watershed and Its Influencing Factors: An Example from Xueyudong Underground River System, Chongqing].

High time-resolution auto-monitoring techniques were used to obtain the data for TOC and hydrogeochemistry of groundwater, and air temperature and precipitation from August 2014 to September 2015 in Xueyu Cave karst watershed, Southwest China, and then the principal component regression model was used to reveal the variation of TOC in groundwater and its influencing factors. The results indicated that there were significant variations of the TOC and hydrogeochemistry of groundwater in seasonal timescale. The temperature and specific conductance (SpC) of groundwater showed higher values in summer and lower values in winter; while an opposite variation pattern for pH in groundwater was observed, and the TOC and turbidity of groundwater showed higher values in winter and summer seasons and lower values in spring and autumn seasons. Meanwhile, high time-resolution data revealed that the TOC of groundwater responded quickly to rainfall events with different intensities. Generally, an increasing trend for TOC in groundwater was observed during raining and a decreasing trend for TOC in groundwater was shown after rainfall events, especially after storm events due to the dilution effect of rainfall. The export and variations of the TOC in groundwater were mainly controlled by the precipitation and discharge of underground river in the study area, as revealed by the principal component regression model. The TOC increased with the increase of the precipitation, discharge and turbidity of groundwater, and declined with the increase of air temperature and pH of groundwater.