Data di Pubblicazione:
2006
Citazione:
Gene-trap lines identify guard-cell specific genes in Arabidopsis / L. Simoni, E. Cominelli, C. Tonelli, M. Galbiati - In: Proceedings of the 50. Italian Society of Agricultural Genetics Annual Congress[s.l] : Società Italiana di Genetica Agraria, 2006. - ISBN 88-900622-7-4. - pp. C.08-C.08 (( Intervento presentato al 50. convegno Congresso annuale della Società Italiana di Genetica Agraria tenutosi a Ischia nel 2006.
Abstract:
Drought is a major environmental issue contributing to crop losses. Plant breeders are facing
the challenge of designing new crops that are more efficient at water use and engineering plants that
are resistant to drought. Land plants lose over 95% of their water via transpiration through stomatal
pores, distributed on the surface of leaves and stems. The opening and closing of the pore is
mediated by turgor-driven volume changes of two surrounding guard cells. These highly specialized
cells integrate internal signals and environmental stimuli to modulate stomatal aperture for plant
survival under diverse conditions. Engineering of stomatal responses in mutant or transgenic plants
represents a promising tool to design new crops with a more sustainable water use and opens new
possibilities to improve plant survival and productivity during drought. Genetic manipulation of
stomatal activity relies on the availability of guard cell-specific mutations and promoters to avoid
undesired effects on plant growth and development. Gene trap insertion lines, in which endogenous
proteins are fused to reporter proteins, are particularly suitable for identification of genes whose
expression is restricted to specific domains (i.e. guard cells). Gene trap lines also provide a
powerful tool for functional studies, since gene trap insertions often disrupt the tagged genes and
give rise to mutant phenotypes. We employed a large scale gene trap screen to identify genes
expressed in guard cells and the promoters that drive their specific expression. In collaboration with
the other members of the Exon Trapping Insert Consortium (EXOTIC), we established the
expression pattern of the GUS reporter gene in approximately 20,000 Arabidopsis gene trap lines.
Among the 1153 lines showing GUS activity in leaf tissues, we identified 5 lines in which the
reporter gene was exclusively or preferentially expressed in guard cells. Here we report the results
of i) the detailed analysis of the spatial and developmental profiles of GUS expression in the gene
trap lines, ii) the identification of the genomic insertion sites of the gene trap element iii) the
analysis of the expression pattern of the tagged gene under standard and stress conditions, and iv)
the bioinformatics analysis of the promoter regions of the guard cell-specific genes. All together,
our results indicate that the gene trap lines isolated in the screen provide valuable marker lines to
study pathways that are unique to guard cells, a powerful tool for reverse genetics analyses of guard
cell-specific genes, and a precious source of guard cell-specific regulatory regions.
Tipologia IRIS:
03 - Contributo in volume
Keywords:
stomata ; guard cells ; plant water loss ; gene-trapping ; Arabidopsis thaliana
Elenco autori:
L. Simoni, E. Cominelli, C. Tonelli, M. Galbiati
Link alla scheda completa:
Titolo del libro:
Proceedings of the 50. Italian Society of Agricultural Genetics Annual Congress