Yuan Xiaohan

SYBR® Green qPCR Screening Methods for Detection of Anti-herbicide Genes in Genetically Modified Processed Products

The use of genetically modified organisms (GMOs) as food products becomes more and more widespread. The European Union has implemented a set of very strict procedures for the approval to grow, import and/or utilize GMOs as food or food ingredients. Thus, analytical methods for detection of GMOs are necessary in order to verify compliance with labelling requirements. There are few effective screening methods for processed GM (genetically modified) products. Three anti-herbicide genes (CP4-EPSPS, BAR and PAT) are common exogenous genes used in commercialized transgenic soybean, maize and rice. In the present study, a new SYBR® Green qPCR screening method was developed to simultaneously detect the three exogenous anti-herbicide genes and one endogenous gene in a run. We tested seven samples of representative processed products (soya lecithin, soya protein powder, chocolate beverage, infant rice cereal, maize protein powder, maize starch, and maize jam) using the developed method, and amplicons of endogenous gene and transgenic fragments were obtained from all the processed products, and the sensitivity was 0.1%. These results indicated that SYBR® Green qPCR screening method was appropriate for qualitative detection of transgenic soybean, maize and rice in processed products.

Vaccaria segetalis activates cellular lactogenesis signaling pathway of dairy cow mammary epithelial cells in vitro

Vaccaria segetalis has very strong effect on lactogenesis, but the mechanism is still unknown. This study aims to reveal the influence of Vaccaria segetalis on cellular lactogenesis signaling pathway of dairy cow mammary epithelial cells (DCMECs). In this study the purified DCMECs was used to screen the most effective concentration of Vaccaria segetalis water decoction for lactogenesis. DCMECs were treated with prolactin (PRL), E (estrogen) or water extraction of Vaccaria segetalis, and many lactogenesis signal molecules in DCMECs including prolactin receptor (PRLR), estrogen receptor a (ERa), p-STAT5, p-mTOR, p100, GARS, PPARg and cyclinD1 were detected by using western blot assay. It was found that Vaccaria segetalis, E and PRL could promote lactogenesis of DCMECs and up-regulate these lactogenesis signal molecules except PPARg. These data reveals that Vaccaria segetalis has a similar role as E or PRL and activates cellular lactogenesis signaling pathway of DCMECs on both the translational and transcriptional levels.