Genome-wide identification of Apetala2 gene family in Hypericum perforatum L and expression profiles in response to different abiotic and hormonal treatments.

The Apetala2 (AP2) gene family of transcription factors (TFs) play important functions in plant development, hormonal response, and abiotic stress. To reveal the biological functions and the expression profiles of AP2 genes in Hypericum perforatum, genome-wide identification of HpAP2 family members was conducted. Methods: We identified 21 AP2 TFs in H. perforatum using bioinformatic methods; their physical and chemical properties, gene structures, conserved motifs, evolutionary relationships, cis-acting elements, and expression patterns were investigated. Results: We found that based on the structural characteristics and evolutionary relationships, the HpAP2 gene family can be divided into three subclasses: euANT, baselANT, and euAP2. A canonical HpAP2 TF shared a conserved protein structure, while a unique motif 6 was found in HpAP2_1, HpAP2_4, and HpAP2_5 from the euANT subgroup, indicating potential biological and regulatory functions of these genes. Furthermore, a total of 59 cis-acting elements were identified, most of which were associated with growth, development, and resistance to stress in plants. Transcriptomics data showed that 57.14% of the genes in the AP2 family were differentially expressed in four organs. For example, HpAP2_18 was specifically expressed in roots and stems, whereas HpAP2_17 and HpAP2_11 were specifically expressed in leaves and flowers, respectively. HpAP2_5, HpAP2_11, and HpAP2_18 showed tissue-specific expression patterns and responded positively to hormones and abiotic stresses. Conclusion: These results demonstrated that the HpAP2 family genes are involved in diverse developmental processes and generate responses to abiotic stress conditions in H. perforatum. This article, for the first time, reports the identification and expression profiles of the AP2 family genes in H. perforatum, laying the foundation for future functional studies with these genes.

The chromosome-scale genome assembly, annotation and evolution of Rhododendron henanense subsp. lingbaoense.

Rhododendron henanense subsp. lingbaoense (hereafter referred to as R. henanense) is an endemic species naturally distributed in the Henan province, China, with high horticultural, ornamental and medicinal value. Herein, we report a de novo genome assembly for R. henanense using a combination of PacBio long read and Illumina short read sequencing technologies. In total, we assembled 634.07 Mb with a contig N50 of 2.5 Mb, representing ~96.93% of the estimated genome size. By applying Hi-C data, 13 pseudochromosomes of R. henanense genome were assembled, covering ~98.21% of the genome assembly. The genome was composed of ~65.76% repetitive sequences and 31,098 protein-coding genes, 88.77% of which could be functionally annotated. Rhododendron henanense displayed a high level of synteny with other Rhododendron species from the Hymenanthes subgenus. Our data also suggests that R. henanense genes related to stress responses have undergone expansion, which may underly the unique abiotic and biotic stress resistance of the species. This alpine Rhododendron chromosome-scale genome assembly provides fundamental molecular resources for germplasm conservation, breeding efforts, evolutionary studies, and elucidating the unique biological characteristics of R. henanense.

Characterization and transferability of microsatellites for Gentiana lawrencei var. farreri (Gentianaceae).

PREMISE OF THE STUDY: Microsatellite markers were developed for a medicinal herb, Gentiana lawrencei var. farreri (Gentianaceae), for the future assessment of population genetic structure and potential hybridization events with related taxa. METHODS AND RESULTS: Using the 454 FLX+ sequencing platform, we obtained 81,717 clean reads with an average length of 291 bp. A total of 3031 primer pairs were designed, and 96 were selected for validation. A set of 20 fluorescently labeled primer pairs was further selected and screened for polymorphisms in three G. lawrencei var. farreri populations and one G. veitchiorum population. Among the four populations, the average number of alleles per locus was 15.2. Finally, a set of 17 unlinked loci were determined to be in Hardy-Weinberg equilibrium after two linked loci were removed. CONCLUSIONS: The identified simple sequence repeat markers will be useful for genetic diversity and evolution studies in G. lawrencei var. farreri and related taxa.

Precise Diagnosis and Treatment of Thymic Epithelial Tumors Based on Molecular Biomarkers.

Thymic epithelial tumors (TETs), including thymoma and thymic carcinoma, are rare malignant tumors. The mainstay of treatment patients with TET is surgical resection, and chemotherapy is necessary for patients with tumor invasion or metastasis who are unable to undergo complete radical excision. However, for those patients who are resistant to chemotherapy, targeted therapy has become the most popular tumor treatment program, as well as for thymic tumors. Many genes implicated in tumorigenesis and metastasis have also been reported to be therapeutic targets in thymic malignancies. A significant advance in TET treatment may derive from the identification of novel molecular biomarkers that can improve the diagnosis, prognosis, and treatment of tumors. We review a number of case reports and small clinical trials reporting that a few inhibitors, such as sorafenib and sunitinib, are effective in the treatment of thymoma. In this review, we describe the current potential drug targets and their roles in the development of thymic malignancy.

[Research on the features of DNA damage in nasopharyngeal carcinoma patients of normal constitution and abnormal constitution and in high-risk population of nasopharyngeal carcinoma].

OBJECTIVE: To explore the features of DNA damage in nasopharyngeal carcinoma (NPC) patients of normal constitution and abnormal constitution and in high-risk population of NPC. METHODS: Using single cell gel electrophoresis technique, the DNA damage of peripheral blood lymphocytes was detected in 28 healthy subjects, 27 in high-risk population of NPC, and 13 NPC patients at their first visits. The DNA damage was detected in the populations of normal constitution and of abnormal constitution. The tail length, the tail moment, and the tail DNA% were taken as the indices of DNA damage. RESULTS: The tail length was (35.77 +/- 4.22) microm, the tail moment was (8.10 +/- 1.63) microm, and the tail DNA% was 57.48% +/- 4.63% in NPC patients. They were (15.25 +/- 4.15) microm, (5.01 +/- 1.92) microm, and 31.99% +/- 4. 11% in high-risk population of NPC. They were (14.31 +/- 3.64) microm, (4. 37 +/- 1.80) microm, and 29. 89% +/- 3. 15% in healthy subjects. There was statistical difference in the three indices among the three populations (P <0.05). In all the three populations, more DNA damage existed in those of abnormal constitution than in those of normal constitution (P <0.05). CONCLUSIONS: Obvious instability of genetic materials exists in NPC patients, manifested as severe DNA damage of lymphocytes. In all the three populations, more DNA damage existed in those of abnormal constitution than in those of normal constitution.

Paris chinensis dioscin induces G2/M cell cycle arrest and apoptosis in human gastric cancer SGC-7901 cells.

AIM: To investigate the anti-tumor effects of Paris chinensis dioscin (PCD) and mechanisms regarding cell cycle regulation and apoptosis in human gastric cancer SGC-7901 cells. METHODS: Cell viability was analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. Cell apoptosis was evaluated by flow cytometry and laser scanning confocal microscope (LSCM) using Annexin-V/propidium iodide (PI) staining, and the cell cycle was evaluated using PI staining with flow cytometry. Intracellular calcium ions were detected under fluorescence microscope. The expression of cell cycle and apoptosis-related proteins cyclin B1, CDK1, cytochrome C and caspase-3 was measured by immunohistochemical staining. RESULTS: PCD had an anti-proliferation effect on human gastric cancer SGC-7901 cells in a dose- and time-dependent manner. After treatment of SGC-7901 cells with PCD, apoptosis appeared in SGC-7901 cells. Morphological changes typical of apoptosis were also observed with LSCM by Annexin V/PI staining, and the cell number of the G0/G1 phase was decreased, while the number of cells in the G2/M phase was increased. Cell cycle-related proteins, such as cyclin B1 and CDK1, were all down-regulated, but caspase-3 and cytochrome C were up-regulated. Moreover, intracellular calcium accumulation occurred in PCD-treated cells. CONCLUSION: G2/M phase arrest and apoptosis induced by PCD are associated with the inhibition of CDK-activating kinase activity and the activation of Ca(2+)-related mitochondrion pathway in SGC-7901 cells.