Abstract
AbstractThree members of the Arabidopsis AINTEGUMENTA-LIKE/PLETHORA (AIL/PLT) transcription factor family, AIL5/PLT5, AIL6/PLT3, and AIL7/PLT7, exhibit partially overlapping roles with AINTEGUMENTA (ANT) during flower development. Loss of ANT function alone results in smaller floral organs and female sterility indicating that some ANT functions cannot be provided by these related transcription factors. Previously, we showed that expression of AIL6 at the same levels and spatial pattern as ANT could largely rescue the defects of ant mutants. This suggested that the functional differences between ANT and AIL6 were primarily a consequence of expression differences. Here, we investigated the functional differences between ANT and both AIL5 and AIL7 by expressing these two AILs under the control of the ANT promoter. We found that only ANT:gAIL5 lines with much higher amounts of AIL5 mRNA as compared with ANT could compensate for loss of ANT function. ANT:gAIL7 lines with AIL7 mRNA levels similar to those of ANT were able to rescue some but not all aspects of the ant mutant phenotype. Thus, expression differences alone cannot explain the functional differences between ANT and these two related proteins. Studies in yeast show that AIL5 and AIL7 have lower transcriptional activation activities as compared with ANT and AIL6 when bound to the consensus ANT DNA binding site. Our results suggest that differences in both expression and protein activity contribute to the functional specificity of ANT compared with AIL5 and AIL7.
Funder
National Science Foundation
Publisher
Springer Science and Business Media LLC
Subject
Plant Science,Genetics,Agronomy and Crop Science,General Medicine
Reference33 articles.
1. Baker SC, Robinson-Beers K, Villanueva JM, Gaiser JC, Gasser CS (1997) Interactions among genes regulating ovule development in Arabidopsis thaliana. Genetics 145:1109–1124
2. Bechtold N, Ellis J, Pelletier G (1993) In planta Agrobacterium mediated gene transfer by infiltration of adult Arabidopsis thaliana plants. CR Acad Sci Ser III Sci Vie 316:1194–1199
3. Briggs GC, Osmont KS, Shindo C, Sibout R, Hardtke CS (2006) Unequal genetic redundancies in Arabidopsis - a neglected phenomenon? Trends Plant Sci 11:1360–1385
4. Czechowski T, Stitt M, Altmann T, Udvardi MK, Scheible W-R (2005) Genome-wide identification and testing of superior reference genes for transcript normalization in Arabidopsis. Plant Physiol 139:5–17
5. Elliott RC, Betzner AS, Huttner E, Oakes MP, Tucker WQJ, Gerentes D, Perez P, Smyth DR (1996) AINTEGUMENTA, an APETALA2-like gene of Arabidopsis with pleiotropic roles in ovule development and floral organ growth. Plant Cell 8:155–168