Poster: Vegetative Development

Abs # 418: A screening of gene trap lines expressing a GUS at vascular elements in Arabidopsis

Presenter:	Sawa, Shinichiro , sawa@biol.s.u-tokyo.ac.jp
Authors	Sawa, Shinichiro  (A)   Shingo, Nagawa  (A)   Tomohiko, Kato  (B)   Shusei, Sato  (B)   Satoshi, Tabata  (B)   Hiroo, Fukuda  (A)
Affiliations:	(A): University of Tokyo (B): Kazusa DNA research institute

The vascular system in plants forms a complex but orderly network that connects the leaves and other parts of the shoot with the root. Since the vascular system is responsible for transport of water, nutrients, and signal molecules, a proper formation and patterning of the vascular system is a critical process in plants. A screen of about 50000 gene trap lines of Arabidopsis identified 138 lines expressing a GUS at vascular elements. We categorized the 138 lines into 3 classes. Their GUS expression was observed at vascular tissues (class 1; 34 lines), vascular and some other tissues (class 2; 18 lines), and variable tissues (class 3; 86 lines). In the class 1, 12 of 34 lines showed some defects in developmental events including vascular pattern formation (6 lines), vascular continuity (3 lines), callus-like cell cluster formation (2 lines), and embryo development (4 lines), probably because of gene disruption by the GUS insertion. L10136 plants, heterozygous to the transgene, showed GUS activity at vascular tissues and hydathode. L10136 plants, homozygous to the transgene, showed vascular discontinuity and callus-like cell cluster formation from the hydathode region. L9040 and L12419 also showed GUS activity at vascular tissues, and their homozygotes showed vascular discontinuity. We assumed that the L10136, L9040 and L12419 are responsible for the proper vascular development because of the correlation between the GUS expression pattern and the phenotype. Further analyses of these gene trap lines will guide to the comprehensive understanding of vascular development.