Large-scale screening of Arabidopsis enhancer-trap lines for seed germination-associated genes

• Published in: The Plant journal : for cell and molecular biology 2005-03, Vol.41 (6), p.936-944
• Main Authors: Liu, P.P, Koizuka, N, Homrichhausen, T.M, Hewitt, J.R, Martin, R.C, Nonogaki, H
• Format: Article
• Language: English
• Subjects: Arabidopsis; Arabidopsis - embryology; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis thaliana; beta-glucuronidase; Biological and medical sciences; Botany; embryo; endosperm; enhancer elements; enhancer trap; Fundamental and applied biological sciences. Psychology; Gene expression; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; Gene Library; Genes; Germination; Germination - genetics; Germination and dormancy; Glucuronidase - metabolism; molecular sequence data; nucleotide sequences; Plant physiology and development; reporter genes; screening; seed germination; Seeds; Seeds - metabolism; Seeds - ultrastructure; transgenes
• ISSN: 0960-7412; 1365-313X
• DOI: 10.1111/j.1365-313X.2005.02347.x

Enhancer trap is a powerful approach for identifying tissue- and stage-specific gene expression in plants and animals. For Arabidopsis research, beta-glucuronidase (GUS) enhancer-trap lines have been created and successfully used to identify tissue-specific gene expression in many plant organs. However, limited applications of these lines for seed germination research have been reported. This is probably due to the impermeability of the testa to the GUS substrate. By focusing on the stages between testa and endosperm rupture; we were able to circumvent the testa barrier to the GUS substrate and observe diverse tissue-specific gene expression during germination sensu stricto. One hundred and twenty-one positive subpools of 10 lines out of 1130 were isolated. Approximately 4500 plants from these subpools were grown in a greenhouse and one to seven individual plants exhibiting GUS expression in seeds were isolated for each subpool. This library of the Arabidopsis seed enhancer-trap lines is an efficient tool for identifying seed germination-associated genes. The individual lines from this library will be provided to the international seed biology research community. International collaboration to identify the trapped genes using genome-walking PCR and to characterize the gene functions using knockout plants will significantly enhance our understanding of the molecular mechanisms of seed germination.