Assessing Genetic Structure and Relatedness of Jerusalem Artichoke (<i>Helianthus tuberosus</i>L.) Germplasm with RAPD, ISSR and SRAP Markers

Jerusalem artichoke (Helianthus tuberosus L.) is an old tuber crop with a recently renewed interest in multipurpose improvement, but little effort has been made to characterize its genetic resources. A study was conducted to assess genetic structure and genetic relatedness of 47 diverse Jerusalem artichoke accessions using RAPD, ISSR and SRAP markers. A total of 296 (87.1%) polymorphic bands were detected from 13 RAPD markers;92 (80%) from six ISSR primers;and 194 (88.6%) for nine combinations of SRAP primers. Five optimal clusters were inferred by the STRUCTURE program from the RAPD or ISSR data, while six optimal clusters were found from the SRAP data or combined marker data. Significant linear relationships between the distance matrices for all pairs of individual accessions were detected for all marker pairs and the estimated correlation coefficient was 0.40 for RAPD-ISSR, 0.53 for RAPD-SRAP, and 0.43 for ISSR-SRAP. Based on the combined data, the neighbor-joining clustering of the 47 accessions matched closely with those inferred from the STRUCTURE program. Three ancestral groups were observed for the Canadian germplasm. Most diverse germplasm harbored in the USA collection. These findings not only reveal the compatible patterns of genetic structure and relatedness inferred with three marker types, but also are useful for managing Jerusalem artichoke germplasm and utilizing diverse germplasm for genetic improvement.

Peanut testa extracts enhance anticancer effect of cisplatin against human cholangiocarcinoma cells via modulation of histone deacetylase inhibitory activity

Objective:To investigate the effect of combination treatments of cisplatin and KK4 and ICG15042 peanut testa extracts against cholangiocarcinoma cells in vitro.Methods:The growth inhibition,cell cycle arrest and apoptosis of cholangiocarcinoma cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry analysis,respectively.The levels of proteins involved in apoptosis were assessed using Western blotting assays.The caspase activity was assessed using a colorimetric caspase activity assay.Results:Cisplatin and peanut(KK4 and ICG15042)testa extracts inhibited the growth of cholangiocarcinoma cell lines(KKUM214 and KKU-100 cells)in a dose-and time-dependent manner.The combination treatments reduced cell viability and induced apoptosis of cholangiocarcinoma cells more efficiently than singledrug treatments.Cancer cell death synergistically mediated by cisplatin and peanut testa extracts was observed in KKU-M214 cells(combination index<1.0)but not in KKU-100 cells(combination index>1.0).The combination treatments also increased the subG1 population and caused KKU-M214 cell cycle arrest at S and G2/M phases,which were the combined effects of cisplatin(S phase arrest)and peanut testa extracts(G2/M phase arrest).In addition,p ERK1/2,Ac-H3,Bcl-2 and proteins related to apoptosis,including Bax and caspases 3,8,9,exhibited enhanced expression in KKUM214 cells.The combination treatments caused down-regulation of p53,whereas the expression of p21 was fairly constant when compared with cisplatin single drug treatment.Conclusions:Peanut testa extracts in combination with cisplatin synergistically reduce cell viability and induce apoptosis through stimulation of caspases 3,8 and 9 in KKU-M214 cells.