Journal Article

SPOROCYTELESS/NOZZLE Gene Is Involved in Controlling Stamen Identity in Arabidopsis

Parameswaran, Sriram, Huang, Jian, Liu, Xiaodong, Zhao, Dazhong, Seubert, Brandon, Jia, Gengxiang, Ito, Toshiro, Auer, Max, Rymaszewski, Amy, Owen, Heather A

2009

Overview

The stamen, which consists of an anther and a filament, is the male reproductive organ in a flower. The specification of stamen identity in Arabidopsis (Arabidopsis thaliana) is controlled by a combination of the B genes APETALA3 (AP3) and PISTILLATA, the C gene AGAMOUS (AG), and the E genes SEPALLATA1 (SEP1) to SEP4. The \"floral organ-building\" gene SPOROCYTELESS/NOZZLE (SPL/NZZ) plays a central role in regulating anther cell differentiation. However, much less is known about how \"floral organ identity\" and floral organ-building genes interact to control floral organ development. In this study, we report that ectopic expression of SPL/NZZ not only affects flower development in the wild-type background but also leads to the transformation of petal-like organs into stamen-like organs in flowers of ap2-1, a weak ap2 mutant allele. Moreover, our loss-of-function analysis indicates that the spl/nzz mutant enhances the phenotype of the ag weak allele ag-4. Furthermore, ectopic expression and overexpression of SPL/NZZ altered expression of AG, SEP3, and AP2 in rosette leaves and flowers, while ectopic expression of SPL/NZZ resulted in ectopic expression of AG and SEP3 in the outer whorls of flowers. Our results indicate that the SPL/NZZ gene is engaged in controlling stamen identity via interacting with genes required for stamen identity in Arabidopsis.

• Publisher: American Society of Plant Biologists
• Subject: alleles / Anthers / Arabidopsis / Arabidopsis - genetics / Arabidopsis - growth & development / Arabidopsis - metabolism / Arabidopsis Proteins / Arabidopsis Proteins - genetics / Arabidopsis Proteins - metabolism / Arabidopsis thaliana / Biological and medical sciences / Calyx / cell differentiation / Development and Hormone Action / Epidermal cells / flowering / Flowers / Flowers - genetics / Flowers - growth & development / Flowers - metabolism / Fundamental and applied biological sciences. Psychology / Gene expression regulation / Gene Expression Regulation, Developmental / Gene Expression Regulation, Plant / Genes, Plant / genetics / growth & development / Leaves / metabolism / mutants / Mutation / Nuclear Proteins / Nuclear Proteins - genetics / Nuclear Proteins - metabolism / Petals / Plant cells / Plant physiology and development / Plants / Plants, Genetically Modified / Plants, Genetically Modified - genetics / Plants, Genetically Modified - growth & development / Plants, Genetically Modified - metabolism / Repressor Proteins / Repressor Proteins - genetics / Repressor Proteins - metabolism / RNA, Plant / RNA, Plant - genetics / Stamens