Submitted to: Canadian Journal of Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2017
Publication Date: 4/19/2017
Citation: Jones, R.W., Perez, F.G. 2017. A second set of XEGIP-encoding genes resides on chromosome 8 of potato and tomato. Canadian Journal of Plant Science. 97(5): 917-922.
Interpretive Summary: Plants have many ways of protecting from drought, temperature stress and disease causing microbes. One way plants achieve protection is through production of inhibitory products that block the damaging effects of stress. We have identified two genes producing inhibitory products, shown that they are common to potato and tomato, and tested if they have an effect on a common plant disease. Transgenic potatoes did not show any changes in growth or disease resistance when the inhibitory products were produced. These results will be valuable for researchers conducting research to improve resistance of crop plants to disease causing microbes.
Technical Abstract: Xyloglucan-specific endoglucanase inhibitor proteins (XEGIP) are present in a wide range of dicots, where they are believed to play a role in defense from pathogens. The XEGIPs are generally present as two or three copies, however, they are reported to be present as a cluster of ten copies in potato and tomato on chromosome 1. We have now identified a second set of XEGIP encoding genes, where two inverted copies are present on chromosome 8 of potato (Solanum tuberosum). The same set exists, in the same order, on chromosome 8 of tomato (Solanum pennellii). Transcript expression analysis indicates that XEGIP10 is transcribed only in roots, while XEGIP11 transcripts were not detected under normal growth conditions. Transgenic potatoes (cvs. Bintje and Kennebec) expressing these genes did not show any obvious changes in phenology. Foliar screening of transgenic lines for resistance to Phytophthora infestans did not reveal any enhanced disease resistance.