Ribosomal protein L22-like1 promotes prostate cancer progression by activating PI3K/Akt/mTOR signalling pathway

Prostate cancer (PCa) is one of the most common malignancies in men. Ribosomal protein L22-like1 (RPL22L1), a component of the ribosomal 60 S subunit, is associated with cancer progression, but the role and potential mechanism of RPL22L1 in PCa remain unclear. The aim of this study was to investigate the role of RPL22L1 in PCa progression and the mechanisms involved. Bioinformatics and immunohistochemistry analysis showed that the expression of RPL22L1 was significantly higher in PCa tissues than in normal prostate tissues. The cell function analysis revealed that RPL22L1 significantly promoted the proliferation, migration and invasion of PCa cells. The data of xenograft tumour assay suggested that the low expression of RPL22L1 inhibited the growth and invasion of PCa cells in vivo. Mechanistically, the results of Western blot proved that RPL22L1 activated PI3K/Akt/mTOR pathway in PCa cells. Additionally, LY294002, an inhibitor of PI3K/Akt pathway, was used to block this pathway. The results showed that LY294002 remarkably abrogated the oncogenic effect of RPL22L1 on PCa cell proliferation and invasion. Taken together, our study demonstrated that RPL22L1 is a key gene in PCa progression and promotes PCa cell proliferation and invasion via PI3K/Akt/mTOR pathway, thus potentially providing a new target for PCa therapy.     

Allotransplantation of adult spinal cord tissues after complete transected spinal cord injury: Long-term survival and functional recovery in canines

Science China Life Sciences - Spinal cord injury (SCI), especially complete transected SCI, leads to loss of cells and extracellular matrix and functional impairments. In a previous study, we...     

Testosterone regulates smooth muscle contractile pathways in the rat prostate: emphasis on PDE5 signaling

Testosterone (T) plays a permissive role in the development of benign prostatic hyperplasia (BPH), and phosphodiesterase 5 inhibitors (PDE5is) have been found to be effective for BPH and lower urinary tract symptoms (LUTS) in clinical trials. This study investigated the effect of T on smooth muscle (SM) contractile and regulatory signaling pathways, including PDE5 expression and functional activity in prostate in male rats (sham-operated, surgically castrated, and castrated with T supplementation). In vitro organ bath studies, real-time RT-PCR, Western blot analysis, and immunohistochemistry were performed. Castration heavily attenuated contractility, including sensitivity to phenylephrine with SM myosin immunostaining revealing a disrupted SM cell arrangement in the stroma. PDE5 was immunolocalized exclusively in the prostate stroma, and orchiectomy signficantly reduced PDE5 immunopositivity, mRNA, and protein expression, along with nNOS and ROKβ mRNA, whereas it increased eNOS plus α(1a) and α(1b) adrenoreceptor expression in castrated animals. The PDE5i zaprinast significantly increased prostate strip relaxation to the nitric oxide donor sodium nitroprusside (SNP) in control but not castrated rats. But SNP alone was more effective on castrated rats, comparable with sham treated with SNP plus zaprinast. T supplementation prevented or restored all above changes, including SNP and zaprinast in vitro responsiveness. In conclusion, our data show that T positively regulates PDE5 expression and functional activities in prostate, and T ablation not only suppresses prostate size but also reduces prostatic SM contractility, with several potential SM contraction/relaxation pathways implicated. Zaprinast findings strongly suggest a major role for PDE5/cGMP in this signaling cascade. PDE5 inhibition may represent a novel mechanism for treatment of BPH.     

Genetic Variation Analysis of Mugil cephalus in China Sea Based on Mitochondrial COI Gene Sequences

In this study, genetic diversity and population genetic structure of flathead grey mullet, Mugil cephalus, among four China Sea populations were investigated by COI sequences. All the populations studied had high values of haplotype and nucleotide diversity, except for the Yellow Sea population. In the phylogenetic tree, these haplotypes clustered in two groups, one for the populations from the Bohai and East China seas, and the other from the Yellow and South China seas. Analysis of molecular variance indicated that the northern populations (Bohai and East China) had lower genetic divergence (0.0725, P > 0.05) than that of the southern population (South China) (0.4530-0.6827, P < 0.001), suggesting that two distinct genetic groups exist in Chinese waters. Tests of neutral evolution and mismatch distribution indicated that no historical demographic expansion occurred in these populations. The results provide new information for genetic assessment, fishery management, and conservation of this species.     

Global transcriptional analysis of stress-response strategies in Acidithiobacillus ferrooxidans ATCC 23270 exposed to organic extractant—Lix984n

Acidithiobacillus ferrooxidans (A. ferrooxidans) ATCC 23270 is a model bacteria for bioleaching research. Because of the use of extractant in metal extraction industry, A. ferrooxidans needs to cope with the water-organic two-phase system. To get insight into the molecular response of A. ferrooxidans to organic solvent, global gene expression pattern was examined in A. ferrooxidans ATCC 23270 cells subjected to Lix984n (an organic extractant) using the method of whole-genome DNA microarray. The data suggested that the global response of A. ferrooxidans to Lix984n stress was characterized by the up-regulation of genes involved in pentose phosphate pathway, fatty acid and glutamate biosynthesis. In further study, compared to heterotrophic bacteria in dealing with short-time stress, A. ferrooxidans has a special strategy of continuously enhancing the expression of genes encoding proteins involved in electron transport, such as petI, petII, cyo and cyd. Besides, acrAB-tolC operon encoding organic solvent efflux pump and its positive regulator gene ostR were addressed.     

Algicidal metabolites produced by Bacillus sp. strain B1 against Phaeocystis globosa

The bloom of Phaeocystis globosa has broken out frequently in the coastal areas of China in recent years, which has led to substantial economic losses. This study shows that Bacillus sp. strain B1, which was previously identified by our group, is effective in regulating P. globosa by excreting active metabolites. Heat stability, pH stability and molecular weight range of the algicidal compounds from strain B1 were measured and the results demonstrated that the algicidal activities of these compounds were not affected by pH or temperature variation. The algicidal compounds extracted with methanol were isolated and purified by ODS-A column chromatography and HPLC. The algicidal compounds corresponding to peaks 2–5 eluted from HPLC were further analysed by quadrupole time-of-flight mass spectrometry (Q-TOF–MS). PeakView? Software determined the compounds corresponding to peaks 2–5 to be l-histidine, o-tyrosine, N-acetylhistamine and urocanic acid on the basis of the accurate mass information, the isotopic pattern and MS–MS spectra. Furthermore, these compounds were also able to eliminate Skeletonema costatum, Prorocentrum donghaiense and Heterosigma akashiwo. This is the first report of bacteria-derived algicidal compounds being identified only by Q-TOF–MS and PeakView? Software, and these compounds may be used as the constituents of algicides in the future.     

Roseomonas alkaliterrae sp. nov., isolated from an alkali geothermal soil sample in Tengchong,Yunnan, south-west China

An alkalitolerant, thermotolerant and Gram-stain negative bacterium, designated strain YIM 78007^T, was isolated from an alkaline geothermal soil sample from Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of strain YIM 78007^T were observed to be aerobic and short rod-shaped. The colonies were observed to be orange-red, convex and circular. 16S rRNA gene sequence-based phylogenetic analysis showed that strain YIM 78007^T clustered with members of the genus Roseomonas (with similarities from 97.2 to 92.2 %). Optimal growth of strain YIM 78007 occurs at 40–50 °C and pH 8.0–10.0. The predominant ubiquinone was identified as Q-10 and the major fatty acids were identified as C_18:1 ω7c and C_16:0. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified aminolipids and one unknown phospholipid. The G + C content of the genomic DNA was determined to be 63 mol %. The levels of DNA–DNA hybridization relatedness between strain YIM 78007^T and its closet neighbours (Roseomonas lacus JCM 13283^T and Roseomonas terrae JCM 14592^T) were well below the threshold required for the proposal of a novel species. The results of physiological and biochemical characteristics, the phylogenetic analysis, as well as low DNA–DNA hybridization values, allowed the phenotypic and genotypic differentiation of strain YIM 78007^T from its closest phylogenetic neighbours. Therefore, strain YIM 78007^T is considered to represent a novel species of the genus Roseomonas, for which the name Roseomonas alkaliterrae sp. nov. is proposed. The type strain is YIM 78007^T (=BCRC 80644^T = JCM 19656^T).     

An efficient,widely applicable cryopreservation of Lilium shoot tips by droplet vitrification

We report a straightforward and widely applicable cryopreservation method for Lilium shoot tips. This method uses adventitious shoots that were induced from leaf segments cultured for 4 weeks on a shoot regeneration medium containing 1 mg/l α-naphthaleneacetic acid and 0.5 mg/l thidiazuron. Shoot tips (1.5–2 mm in length) including 2–3 leaf primordia were precultured on Murashige and Skoog (MS; 1962) medium with 0.5 M sucrose for 1 day and then treated with a loading solution containing 0.4 M sucrose and 2 M glycerol for 20 min, followed by a Plant Vitrification Solution 2 (PVS2) treatment for 4 h at 0 °C. Dehydrated shoot tips were transferred onto 2.5 µl PVS2 droplets on aluminum foil strips, prior to a direct immersion into liquid nitrogen for 1 h. Frozen shoot tips were re-warmed in MS medium containing 1.2 M sucrose for 20 min at room temperature, followed by post-thaw culture for shoot regrowth. Shoot regrowth levels ranged from 42.5 % for L. longiflorum × Oriental ‘Triumphator’ to 87.5 % for L. Oriental hybrid ‘Siberia’, with a mean shoot regrowth level of 67.1 % across the six diverse Lilium genotypes tested. Histological observations found that the survival patterns were similar in cryopreserved shoot tips of ‘Triumphator’ and ‘Siberia’. Assessments using inter-simple sequence repeat markers found no differences in regenerants recovered from the control stock cultures and from cryopreserved shoot tips in ‘Triumphator’ and ‘Siberia’. This Lilium droplet-vitrification cryopreservation method is efficient, simple and widely applicable for the long-term conservation of lily genetic resources.