Metabolome and transcriptome profiling of Theobroma cacao provides insights into the molecular basis of pod color variation

Journal of Plant Research - The Theobroma cacao presents a wide diversity in pod color among different cultivars. Although flavonoid biosynthesis has been studied in many plants, molecular...     

Molecular cloning and expression analysis of the sucrose transporter gene family from Theobroma cacao L.

In this study, we performed cloning and expression analysis of six putative sucrose transporter genes, designated TcSUT1, TcSUT2, TcSUT3, TcSUT4, TcSUT5 and TcSUT6, from the cacao genotype ‘TAS-R8’. The combination of cDNA and genomic DNA sequences revealed that the cacao SUT genes contained exon numbers ranging from 1 to 14. The average molecular mass of all six deduced proteins was approximately 56 kDa (range 52 to 66 kDa). All six proteins were predicted to exhibit typical features of sucrose transporters with 12 trans-membrane spanning domains. Phylogenetic analysis revealed that TcSUT2 and TcSUT4 belonged to Group 2 SUT and Group 4 SUT, respectively, and the other TcSUT proteins were belonging to Group 1 SUT. Real-time PCR was conducted to investigate the expression pattern of each member of the SUT family in cacao. Our experiment showed that TcSUT1 was expressed dominantly in pods and that, TcSUT3 and TcSUT4 were highly expressed in both pods and in bark with phloem. Within pods, TcSUT1 and TcSUT4 were expressed more in the seed coat and seed from the pod enlargement stage to the ripening stage. TcSUT5 expression sharply increased to its highest expression level in the seed coat during the ripening stage. Expression pattern analysis indicated that TcSUT genes may be associated with photoassimilate transport into developing seeds and may, therefore, have an impact on seed production.     

Metabolic regulation of protein N-alpha-acetylation by Bcl-xL promotes cell survival

Previous experiments suggest a connection between the N-alpha-acetylation of proteins and sensitivity of cells to apoptotic signals. Here, we describe a biochemical assay to detect the acetylation status of proteins and demonstrate that protein N-alpha-acetylation is regulated by the availability of acetyl-CoA. Because the antiapoptotic protein Bcl-xL is known to influence mitochondrial metabolism, we reasoned that Bcl-xL may provide a link between protein N-alpha-acetylation and apoptosis. Indeed, Bcl-xL overexpression leads to a reduction in levels of acetyl-CoA and N-alpha-acetylated proteins in the cell. This effect is independent of Bax and Bak, the known binding partners of Bcl-xL. Increasing cellular levels of acetyl-CoA by addition of acetate or citrate restores protein N-alpha-acetylation in Bcl-xL-expressing cells and confers sensitivity to apoptotic stimuli. We propose that acetyl-CoA serves as a signaling molecule that couples apoptotic sensitivity to metabolism by regulating protein N-alpha-acetylation.     

In vitro evaluation of the anti-estrogenic activity of hydroxyl substituted diphenylnaphthyl alkene ligands for the estrogen receptor

There is still a need for additional scaffolds to further explore tissue selectivity and improving efficacy of selective estrogen receptor modulators (SERMs). A series of hydroxyl substituted diphenylnaphthyl alkene ligands for the two estrogen receptors are described that arose from an initial de novo designed diphenylnaphthyl propylene ligand 1. All compounds gave K(i)s under 10 nM when assayed in the presence of ERalpha. Generally these compounds had very high affinity for both ER isotypes. Moving the hydroxyl group on naphthalene from the 6- to the 5-position of the alpha-naphthalene attached compounds (6b and 6e vs 6c and 6f) had little affect on ER binding nor did altering the position of the naphthalene attachment (alpha or beta) to the alkene moiety. In transfection assays none of the compounds displayed agonistic activity in the absence of E(2). In MCF-7 proliferation assays 6a-d, 6f and 12a-c successfully abrogated E(2) stimulation and resulted in greater than 50% inhibition at 1 microM, a level of efficacy similar to that obtained when the cells were treated with raloxifene. Our results show that this new class of SERMs are good candidates for further study as therapeutic agents for the treatment of breast cancer and osteoporosis.     

不同包膜控释尿素对农田土壤氨挥发的影响

为了探索包膜控释尿素土壤氨挥发损失规律特征和提高肥料氮素利用率,采用小麦玉米轮作田间试验,通过与普通尿素进行对比,运用土壤氨挥发原位测定方法——通气法系统研究了硫包膜和树脂包膜控释尿素的施用对小麦玉米轮作农田土壤氨挥发的影响.研究结果表明:在两种施氮量水平下(210 kg/hm2和300 kg/hm2),与普通尿素相比,硫包膜和树脂包膜控释尿素在小麦基肥期、小麦追肥期和玉米施肥期的施用均减少了土壤氨挥发的累积损失量,分别达35.1％-54.3％、59.6％-75.2％、65.6％-98.1％;有效降低了土壤氨挥发通量峰值且延迟其出现时间3-8 d,并能延缓土壤氨挥发主要阶段的时间分别为4-12 d、5-12 d.在小麦玉米轮作周年中,控释尿素土壤氨挥发累积损失量为28.39-43.35 kg/hm2,土壤氨挥发损失率为4.48％-5.63％,控释尿素时段土壤氨挥发通量比普通尿素降低了51.0％-70.8％;且树脂包膜控释尿素的施用降低小麦玉米轮作农田土壤氨挥发的效果优于硫包膜控释尿素.     

CAPS and SCAR markers linked to maintenance of self-incompatibility developed from SP11 in Brassica napus L.

Difficulty in propagating self-incompatible lines on a large scale limits the utilization of self-incompatibility in Brassica napus. The self-incompatible line S-1300 and its maintainer Bing409 were used in this study to develop molecular markers linked to the maintenance for the self-incompatibility of S-1300. The maintenance of Bing409 is controlled by one recessive gene. SLG-specific primer pairs PS5/PS15 and PS3/PS21 cannot be used to discriminate the S haplotypes of Bing409 and S-1300. BrSRK-60-based primer pair SRKa-L and SRKa-R produced one band in S-1300, but no band in Bing409. BrSP11-60-based primer pair SP11a-L and SP11a-R gave rise to one band in S-1300 and Bing409, but their length was different. Compared with SP11-S-1300, SP11-Bing409 had two deletions of 2 and 9 bp. One co-dominant cleaved amplified polymorphic sequence marker was developed; two dominant sequence characterized amplified region markers linked to the maintenance were developed on the 9 bp deletion. The markers co-segregated with self-incompatibility phenotypes in S-1300 × Bing409 F₂, two BC₁ and eight BC₁F₂ populations. We have shown a way to develop PCR markers linked to the S haplotype of B. napus, which could be very helpful for marker-assisted selection in B. napus hybrid breeding.     

Construction of co-expression modules related to survival by WGCNA and identification of potential prognostic biomarkers in glioblastoma

Glioblastoma (GBM) is a malignant brain tumour with poor prognosis. The potential pathogenesis and therapeutic target are still need to be explored. Herein, TCGA expression profile data and clinical information were downloaded, and the WGCNA was conducted. Hub genes which closely related to poor prognosis of GBM were obtained. Further, the relationship between the genes of interest and prognosis of GBM, and immune microenvironment were analysed. Patients from TCGA were divided into high- and low-risk group. WGCNA was applied to the high- and low-risk group and the black module with the lowest preservation was identified which could distinguish the prognosis level of these two groups. The top 10 hub genes which were closely related to poor prognosis of patients were obtained. GO analysis showed the biological process of these genes mainly enriched in: Cell cycle, Progesterone-mediated oocyte maturation and Oocyte meiosis. CDCA5 and CDCA8 were screened out as the genes of interest. We found that their expression levels were closely related to overall survival. The difference analysis resulted from the TCGA database proved both CDCA5 and CDCA8 were highly expressed in GBM. After transfection of U87-MG cells with small interfering RNA, it revealed that knockdown of the CDCA5 and CDCA8 could influence the biological behaviours of proliferation, clonogenicity and apoptosis of GBM cells. Then, single-gene analysis was performed. CDCA5 and CDCA8 both had good correlations with genes that regulate cell cycle in the p53 signalling pathway. Moreover, it revealed that high amplification of CDCA5 was correlated with CD8⁺ T cells while CDCA8 with CD4⁺ T cells in GBM. These results might provide new molecular targets and intervention strategy for GBM.