TITLE:
An Efficient Intragenic Vector for Generating Intragenic and Cisgenic Plants in Citrus
AUTHORS:
Chuanfu An, Vladimir Orbović, Zhonglin Mou
KEYWORDS:
Intragenesis/Cisgenesis; Citrus; Selectable Marker; Transgenesis
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.11,
November
13,
2013
ABSTRACT: Genetic transformation has
become a promising tool for improvement of a variety of crop species. However,
transferring genes across species, the presence of selectable marker genes, and
bacteria-derived vector backbone sequences have raised considerable health and
environmental concerns. Intragenic vector system-based intragenesis/cisgenesis
is a new method using transgenic approach to achieving traditional breeding
objectives but circumventing many of the associated shortcomings. We report
here the development of an intragenic vector by assembling a T-DNA-like fragment
and a buffering sequence following the left border from Citrus clementina into the backbone of the binary vector pCB302. Recovery
of citrus regenerants is performed under non-selective conditions and positive
intra-/cisgenic regenerants were identified through PCR analysis. Transformation
efficiencies obtained in Arabidopsis and “Duncan” grapefruit were ~3% and ~0.67%, respectively,
demonstrating the potential of the system for development of “foreign DNA-free”
intra-/cisgenic citrus cultivars.