Tetradecyl 2,3-dihydroxybenzoate promotes functional recovery after spinal cord injury in adult rats.

Tetradecyl 2,3-dihydroxybenzoate (ABG001) is a small molecule separated from gentian extract that has a similar effect to nerve growth factor. It is not clear whether it can promote functional recovery in animals suffering from a central nervous system injury. In order to explore the role of ABG001 in restoration of tissue structure and motor function of rats with spinal cord injury (SCI), ABG001 (0.4 mg/kg) was administered intraperitoneally. Subsequently, behavioral assessments and morphological studies were performed to detect recovery of hind limb motor function and neuroregeneration. The results showed that compared with DMSO group, the rats in the ABG treatment group had better performance in BBB score and grip strength test (P < 0.05), the area of necrosis was smaller (P < 0.05), GFAP expression was significantly reduced (P < 0.01), and Map-2 expression was significantly increased (P < 0.01). Additionally, after ABG treatment, the number of fluorogold positive cells transported reversely to red nucleus increased (P < 0.05). The results suggest that ABG001 can promote recovery of hind limb motor function in rats with SCI, which may be related to its functions of inhibiting glial cell proliferation and promoting neuroregeneration.

Chloroplast analysis of Zelkova schneideriana (Ulmaceae): genetic diversity, population structure, and conservation implications.

Zelkova schneideriana is endemic to China and belongs to the Ulmaceae. It is listed as a Near Threatened species in the China Biodiversity Red Data Book. We conducted a phylogeographical study of two chloroplast regions (psbA-trnH and trnG-trnM) in several Chinese Z. schneideriana populations, in order to examine the genetic diversity, population structure, and evolutionary history of the species. In all, 10 haplotypes were detected. The population from Sangzhi, Hunan, had the highest nucleotide diversity (π = 0.00653) and haplotype diversity (HD = 1.000), and should be considered the most suitable population to be protected under an in situ conservation strategy. Seed collections from as many individuals as possible in other populations would preserve the genetic diversity of Z. schneideriana.

Development and characterization of polymorphic microsatellite markers for Castanopsis hystrix (Fagaceae).

Castanopsis hystrix is one of the most important and dominant species in evergreen broad-leaved forests in subtropical China. However, the population of this species undergone severe decline because of deforestation over the past 2 decades. For both conservation and forestry management, it is essential to develop molecular markers for C. hystrix. We identified 11 microsatellite loci in 2 wild populations. The number of alleles ranged from 3-11, with an average of 6.45 alleles per locus. The observed and expected heterozygosities ranged from 0.640-0.960 and from 0.676-0.910, respectively.

Cytochalasin B inhibits the proliferation of human glioma U251 cells through cell cycle arrest and apoptosis.

Cytochalasin B (CB) is known to inhibit a number of cancer types, but its effects on gliomas are unknown. We examined the in vitro effects of CB on the proliferation of human glioma U251 cells, as well as determined its mechanism of action. Cell proliferation was determined using CCK-8. The effect of CB on U251 cell morphology was observed under a transmission electron microscope. Cell cycle distribution was assessed using propidium iodine and Giemsa staining, and cell apoptosis was determined by annexin V-fluorescein isothiocyanate/propidium iodide. Cell cycle-related proteins were determined by Western blot. CB effectively inhibited U251 cell proliferation in a dose- and time-dependent manner. The 24, 48, 72, and 96 h IC50 values were 6.41 x 10(-2), 9.76 x 10(-4), 2.57 x 10(-5), and 2.08 x 10(-5) M, respectively. CB increased the proportion of cells in the G2/M phase in a dose-dependent manner, thus increasing the mitotic index and decreasing cdc2 and cyclin B1 protein levels. CB induced morphological changes in the cytoskeleton. Additionally, 10(-5) M CB induced apoptosis in 23.4 ± 0.5% of U251 cells (P < 0.05 vs control group). Caspase-3, -8, and -9 activities were increased after CB treatment. CB inhibited U251 glioma cell proliferation by damaging the microfilament structure. CB also induced glioma cell apoptosis, suggesting that it may be an effective therapeutic agent against gliomas.

Isolation and characterization of polymorphic microsatellite loci from Zelkova schneideriana Hand.-Mazz.

Zelkova schneideriana is a highly valued hardwood species. An improved technique for isolating codominant compound microsatellite markers was used to develop simple sequence repeat markers for Z. schneideriana. A total of 12 microsatellite loci were identified. Overall, the number of alleles per locus ranged from 8-19, with an average of 11.75. Observed heterozygosity and expected heterozygosity values ranged from 0.109-0.709 and 0.832-0.929, respectively. Polymorphic information content is from 0.803-0.915, with an average of 0.854. These markers will be very important for future research related to the genetic diversity, population structure, patterns of gene flow, and mating system of this species.

Transcriptome profiling of the crofton weed gall fly Procecidochares utilis.

Procecidochares utilis is a tephritid gall fly, which is known to be an effective biological agent that can be used to control the notoriously widespread crofton weed Eupatorium adenophorum. Despite its importance, genetic resources for P. utilis remain scarce. In this study, 1.2 Gb sequences were generated using Illumina paired-end sequencing technology. De novo assemblies yielded 491,760 contigs, 90,474 scaffolds, and 58,562 unigenes. Among the unigenes, 34,809 (59.44%) had a homologous match against the National Center for Biotechnology Information non-redundant protein database by translated Basic Local Alignment Search Tool (BlastX) with a cut-off E-value of 10(-5). Among the unigenes, 57,627 were classified in the Gene Ontology database, 15,910 were assigned to Clusters of Orthologous Groups, and 38,565 were found in Kyoto Encyclopedia of Genes and Genomes. In addition, 5723 simple sequence repeats (SSRs) were discovered based on the unigene sequences. The transcriptome sequences and SSRs obtained represent a major molecular resource for P. utilis, which will extend our knowledge of the comparative and functional genomics of this organism and enable population genomic and gene-based association studies of the gall fly.

Impact of MTHFR polymorphisms on methylation of MGMT in glioma patients from Northeast China with different folate levels.

Hypomethylation of the O6-methylguanine-DNA-methyltransferase (MGMT) promoter in glioma cells has been associated with temozolomide resistance. S-adenosylmethionine (SAM), which is produced during folate metabolism, is the main source of methyl groups during DNA methylation. As a key enzyme during folate metabolism, polymorphisms of 5,10-methylenetetrahydrofolate reductase (MTHFR) may regulate folate end-products. We investigated the effect of typical polymorphisms of MTHFR (C677T and A1298C) on MGMT methylation based on different serum folate levels in patients with glioma from Northeast China. A total of 275 patients with glioma and 329 without malignant tumors were tested. Serum folate concentration was assayed by using the electrochemiluminescence immunoassay. MTHFR polymorphisms were detected by Taqman-Fluorescence quantitative polymerase chain reaction (PCR). Methylation-specific PCR was used to assess MGMT methylation. The constituent ratio of glioma patients below the serum folate biological reference value was significantly higher than that of the control population (P < 0.001). In patients with oligodendroglioma and glioblastoma, heterozygotes for the A1298C mutation were found in higher frequency than homozygotes or wild types (oligodendroglioma, P < 0.001; glioblastoma, P < 0.01). When grouped by the median or biological reference value of serum folate, only homozygotes for C677T with low levels of folate were significantly associated with decreased methylation of MGMT (median, P < 0.001; biological reference value, P = 0.036). These data suggest that, in combination with a negative folate balance in glioma patients, T/T genotypes in MTHFR C677T may be associated with MGMT demethylation.

Molecular characterization and functional analysis of sheep thyroid transcription factor-1.

Thyroid transcription factor-1 (TTF-1), a member of the Nkx2 family of homeodomain-containing proteins, is involved in binding to and in activating the promoters of several important genes in the thyroid, lungs, and brain, and in regulating expression of these tissue-specific genes. We investigated potential roles of sheep (Ovis aries) TTF-1 in regulating cell fate and organ morphogenesis and in controlling puberty and reproductive capability of females. We amplified and cloned the sheep TTF-1 full-length DNA for the first time, analyzed its functional domains and regions, predicted molecular structure of its homeodomain and DNA-binding sites, and examined its expression in pituitary, brain, thyroid gland, ovary, and hypothalamus. We found that sheep TTF-1 has a high degree of homologous identity with that of other mammals, and it has several important domains including domain N, DNA-binding domain, domain C, TN-domain, domain I, and NK2-SD. The DNA-binding domain of sheep TTF-1 has 10 potential DNA-binding sites and is a novel mammalian homeodomain that shows considerable sequence homology with the corresponding rat homeodomain. Several functional regions in sheep TTF-1 share high sequence identity with rat TTF-1, indicating that these regions may have the same activity as in the rat. Expression of TTF-1 in several specific tissues implies that sheep TTF-1 in involved in sheep sexual development and reproductive capability. These results suggest a role of sheep TTF-1 in enhancing sheep reproduction performance and we propose it as a candidate gene for selection.