Summary
Control of seed size involves complex interactions among the zygotic embryo and endosperm, the maternally derived seed coat, and the parent plant. Here we describe a mutant in Arabidopsis, megaintegumenta (mnt), in which seed size and weight are dramatically increased. One factor in this is extra cell division in the integuments surrounding mnt mutant ovules, leading to the formation of enlarged seed coats. Unusually for integument mutants, mnt does not impair female fertility. The mnt lesion also has pleiotropic effects on vegetative and floral development, causing extra cell division and expansion in many organs. mnt was identified as a mutant allele of AUXIN RESPONSE FACTOR 2 (ARF2), a member of a family of transcription factors that mediate gene expression in response to auxin. The mutant phenotype and gene expression studies described here provide evidence that MNT/ARF2 is a repressor of cell division and organ growth. The mutant phenotype also illustrates the importance of growth of the ovule before fertilization in determining final size of the seed.
Footnotes
- Accepted November 1, 2005.
Article navigation
Related articles
Cited by...
More in this TOC section
Similar articles
Other journals from The Company of Biologists
Kathryn Virginia Anderson (1952-2020)
Developmental geneticist Kathryn Anderson passed away at home on 30 November 2020. Tamara Caspary, a former postdoc and friend, remembers Kathryn and her remarkable contribution to developmental biology.
Zooming into 2021
In a new Editorial, Editor-in-Chief James Briscoe and Executive Editor Katherine Brown reflect on the triumphs and tribulations of the last 12 months, and look towards a hopefully calmer and more predictable year.
Read & Publish participation extends worldwide
Over 60 institutions in 12 countries are now participating in our Read & Publish initiative. Here, James Briscoe explains what this means for his institution, The Francis Crick Institute. Find out more and view our full list of participating institutions.
Upcoming special issues
Imaging Development, Stem Cells and Regeneration
Submission deadline: 30 March 2021
Publication: mid-2021
The Immune System in Development and Regeneration
Guest editors: Florent Ginhoux and Paul Martin
Submission deadline: 1 September 2021
Publication: Spring 2022
Both special issues welcome Review articles as well as Research articles, and will be widely promoted online and at key global conferences.
Development presents...
Our successful webinar series continues into 2021, with early-career researchers presenting their papers and a chance to virtually network with the developmental biology community afterwards. Sign up to join our next session:
10 February
Time: 13:00 (GMT)
Chaired by: preLights