title: The PRETTY FEW SEEDS2 gene encodes an Arabidopsis homeodomain protein that regulates ovule development.
abstract: The PRETTY FEW SEEDS2 gene encodes a homeodomain protein that regulates ovule development. In peptide alignments spanning the homeodomain and the WOX domain, PFS2 shared 95% amino acid identity with the PRESSED FLOWER and WUSCHEL proteins. In the pfs2-1 allele, the integuments display morphological abnormalities and 95% of the embryo sacs fail to develop properly, which results in reduced fecundity. PFS2 transcripts were most abundant in developing ovules, which accounts for the ovule phenotype in pfs2 mutants. In addition, PFS2 transcripts were present in developing primordia and differentiating organs, but, interestingly, they were absent during cell maturation. Ectopic PFS2 expression interfered with differentiation of primordia from meristems. For most plants, this resulted in fasciated stems, altered phyllotaxy, a cessation of primordia differentiation, or a combination of these. In the plants that made ovules, ectopic PFS2 expression blocked megaspore mother cell differentiation and often impeded polarized growth of the outer integument. PFS2 activity altered AGAMOUS expression, which accounts for some of the gain- and loss-of-function phenotypes. Based on analyses presented here, PFS2 affects either ovule patterning or differentiation.
authors.affiliation: Department of Botany, University of Florida, Gainesville, FL 32611-8526, USA.
authors.forename: Sung Ok
authors.initials: SO
authors.lastname: Park
authors.forename: Zhengui
authors.initials: Z
authors.lastname: Zheng
authors.forename: David G
authors.initials: DG
authors.lastname: Oppenheimer
authors.forename: Bernard A
authors.initials: BA
authors.lastname: Hauser
mesh_terms: D026342:AGAMOUS Protein, Arabidopsis / Q000378:metabolism; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology*; D035264:Flowers / Q000254:growth & development* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000254:growth & development / Q000378:metabolism; D008969:Molecular Sequence Data; D018520:Plant Shoots / Q000254:growth & development / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics
chemical_list: D026342:AGAMOUS Protein, Arabidopsis; D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; C499750:PRETTY FEW SEEDS2 protein, Arabidopsis; D018749:RNA, Plant