Comparative transcriptome analysis and genetic marker development for Diperonia species

• 1、Northwest University, College of Life Sciences, Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), Xi'an 710069

Abstract：Dipteronia Oliver is an endangered Chinese endemic genus belongs to the order of Sapindales and it is a sister genus of Acer with two living species, D. sinensis and D. dyeriana. However, evolutionary studies about this genus were hindered due to the paucity of the comprehensive genomic resources. Here, we obtained transcriptome data sets for two species of Dipteronia using next generation sequencing. By comparing the transcriptomes of both species, a total of 7,814 orthologs were obtained. Estimation of Ka/Ks ratios for 5,435 orthologous pairs revealed that only 30 orthologous pairs had a Ka/Ks ratio significantly greater than 1. However, 4,041 orthologs with a Ka/Ks < 0.5 (p<0.05), suggesting that most genes likely undergo purifying selection. Based on the orthologous unigenes, 1,384 SSRs (simple sequence repeats) and 314 single copy nuclear genes (SCNGs) were identified. Marker validation assay indicated that 87% SSR primer pairs could amplify PCR fragments with the expected sizes in both species and 83% SCNGs could be amplified. Overall, our study provide comprehensive transcriptomic resources which will definitely be helpful for future evolutionary studies of Dipteronia.

Keywords： Dipteronia transcriptome positive selection purifying selection genetic marker