title: The SPOROCYTELESS/NOZZLE gene is involved in controlling stamen identity in Arabidopsis.
abstract: 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.
authors.affiliation: Department of Biological Sciences, University of Wisconsin, Milwaukee, Wisconsin 53211, USA.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Liu
authors.forename: Jian
authors.initials: J
authors.lastname: Huang
authors.forename: Sriram
authors.initials: S
authors.lastname: Parameswaran
authors.forename: Toshiro
authors.initials: T
authors.lastname: Ito
authors.forename: Brandon
authors.initials: B
authors.lastname: Seubert
authors.forename: Max
authors.initials: M
authors.lastname: Auer
authors.forename: Amy
authors.initials: A
authors.lastname: Rymaszewski
authors.forename: Gengxiang
authors.initials: G
authors.lastname: Jia
authors.forename: Heather A
authors.initials: HA
authors.lastname: Owen
authors.forename: Dazhong
authors.initials: D
authors.lastname: Zhao
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D009687:Nuclear Proteins; D018749:RNA, Plant; D012097:Repressor Proteins; C416221:SPL protein, Arabidopsis