The dyad gene is required for progression through female meiosis in Arabidopsis

Siddiqi, I., Ganesh, G., Grossniklaus, U., Subbiah, V. (January 2000) The dyad gene is required for progression through female meiosis in Arabidopsis. Development, 127 (1). pp. 197-207. ISSN 0950-1991

[thumbnail of Paper]
Preview
PDF (Paper)
Grossniklaus Development 2000.pdf - Published Version

Download (1MB) | Preview

Abstract

In higher plants the gametophyte consists of a gamete in association with a small number of haploid cells, specialized for sexual reproduction. The female gametophyte or embryo sac, is contained within the ovule and develops from a single cell, the megaspore which is formed by meiosis of the megaspore mother cell. The dyad mutant of Arabidopsis, described herein, represents a novel class among female sterile mutants in plants, dyad ovules contain two large cells in place of an embryo sac. The two cells represent the products of a single division of the megaspore mother cell followed by an arrest in further development of the megaspore. We addressed the question of whether the division of the megaspore mother cell in the mutant was meiotic or mitotic by examining the expression of two markers that are normally expressed in the megaspore mother cell during meiosis. Our observations indicate that in dyad the megaspore mother cell enters but fails to complete meiosis, arresting at the end of meiosis 1 in the majority of ovules, This was corroborated by a direct observation of chromosome segregation during division of the megaspore mother cell, showing that the division is a reductional and not an equational one. In a minority of dqad ovules, the megaspore mother cell does not divide. Pollen development and male fertility in the mutant is normal, as is the rest of the ovule that surrounds the female gametophyte. The embryo sac is also shown to have an influence on the nucellus in wild type. The dyad mutation therefore specifically affects a function that is required in the female germ cell precursor for meiosis. The identification and analysis of mutants specifically affecting female meiosis is an initial step in understanding the molecular mechanisms underlying early events in the pathway of female reproductive development.

Item Type: Paper
Uncontrolled Keywords: female gametophyte meiosis megasporogenesis megaspore mother cell Arabidopsis thaliana ASYMMETRIC CELL-DIVISION EMBRYO SAC OVULE DEVELOPMENT MEIOTIC DIVISION SEED DEVELOPMENT THALIANA MAIZE MEGASPOROGENESIS FERTILIZATION EMBRYOGENESIS
Subjects: organism description > plant > Arabidopsis
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > genes, structure and function > gene expression
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > genes, structure and function
organs, tissues, organelles, cell types and functions > organelles, types and functions > meiosis
CSHL Authors:
Communities: CSHL labs > Grossniklaus lab
Depositing User: Matt Covey
Date: January 2000
Date Deposited: 31 Jan 2014 16:12
Last Modified: 31 Jan 2014 16:12
Related URLs:
URI: https://repository.cshl.edu/id/eprint/29382

Actions (login required)

Administrator's edit/view item Administrator's edit/view item