Supported by the Ministry of Agricu

Supported by the Ministry of Agriculture of the Czech Republic, Projects No. 1B44068 PUV and No. MZE 0002700604, and by the Ministry of Education, Youth and Sports of the Czech Republic, Project No. MEB 080849.


S2-75

Vol. 27, 2009, Special Issue 2: S2-75–S2-81 Czech J. Food Sci.



European community does not allow import of transgenic papaya into its territory. European jurisdiction requires risk assessment by EFSA (European Food Safety Authority) before authori-sation. For details see EC Regulation 1829/2003. Recently unauthorised GM papaya was catch on EC market (Busch et al. 2004). To control the import detection methods are required. Gener-ally they are PCR based but others are under the development (Anklam et al. 2002; Liu et al. 2004; Monma et al. 2004; Mafra et al. 2008).

GMO contains foreign DNA usually consisting of promotor, coding sequence and terminator for both functional and marker genes. Often, CaMV 35S promoter is used in the construct. So that PCR based methods require isolated DNAs containing target DNA string. For details and principle see e.g. Ovesná et al. (2008). According GM database of the Agbios (AgBios GM Database), which is an internationally respected Canadian company dedicated to providing public policy, regulatory, and risk assessment expertise for products of biotechnology, there are two events of GM papaya event 55-1/63-1 and X17-2. Both traits are resist-ant to viral infection PRSV and both transgenic constructs contain CaMV 35S promoter. Schema of genes inserted into the papaya 55-1 is presented in Figure 1. The gus gene is not presented in line 63-1 compared to 55-1 line.

We aimed in our research to establish reliable protocol for isolation of DNA from raw and candied papaya fruit amplifiable by appropriate method, as the GM papaya is unapproved in EC and the DNA extraction from papaya products was revealed as problematic (Wall et al. 2004).

Here we describe optimised protocol and results of GM screening based on CaMV 35S promoter


p355 PRSVcp t355

p355 gus tNOS

Figure 1. Transgenic contruct of GM papaya. p35S = CaMV 35S promoter (CaMV – Cauliflower mosaic virus); PRSVcp = viral coat protein (PRSV – papaya ringspot potyvirus ); t35S = CaMV 35S terminator (CaMV – Cauliflower mosaic virus); gus = beta-d-glucuronidase (from Escherichia coli); tNOS = A. tumefaciens nopaline synthase (nos) 3'-untrans-lated region. Adapted according: AgBios GM Database and Wall et al. (2004)