Transport of mRNA molecules coding NAC domain protein in grafted pear and transgenic tobacco

Abstract

Grafting is an important cultivation method and recent research on the mechanism of interactions between rootstock nad scion is focused on the long-distance transport of mRNA and small RNAs in the phloem. Among these transportable molecules, NACP gene coding NAM, ATAF1/2, CUC2 (NAC) domain protein might be involved in apical meristem development. Here, we report the transport of NACP mRNA between Chinese pear (Pyrus bretschneideri) cv. Yali (scion) and the wild Pyrus betulaefolia Bunge (rootstock). Our results indicated that NACP mRNA can be transported in both directions from the 3rd to 10th day after micro-grafting. It can also be transported to the shoot apex 30 to 70 cm away from graft-union in 2-year-old grafted trees. For further investigation, transgenic tobaccos with 35S: P. betulaefolia-NACP construct were grafted on wild-type tobaccos (Nicotiana tabacum L. cv. Samsun). The sustainable transport of Pyrus-NACP mRNA through the graft-union occurred from the 15th day after grafting. © 2013 Springer Science+Business Media Dordrecht.