title: Arabidopsis plants deficient in constitutive class profilins reveal independent and quantitative genetic effects.
abstract: BACKGROUND
  The actin cytoskeleton is involved in an array of integral structural and developmental processes throughout the cell. One of actin's best-studied binding partners is the small ubiquitously expressed protein, profilin. Arabidopsis thaliana is known to encode a family of five profilin sequence variants: three vegetative (also constitutive) profilins that are predominantly expressed in all vegetative tissues and ovules, and two reproductive profilins that are specifically expressed in pollen. This paper analyzes the roles of the three vegetative profilin members, PRF1, PRF2, and PRF3, in plant cell and organ development.
  
  
  RESULTS
  Using a collection of knockout or severe knockdown T-DNA single mutants, we found that defects in each of the three variants gave rise to specific developmental deficiencies. Plants lacking PRF1 or PRF2 had defects in rosette leaf morphology and inflorescence stature, while those lacking PRF3 led to plants with slightly elongated petioles. To further examine these effects, double mutants and double and triple gene-silenced RNAi epialleles were created. These plants displayed significantly compounded developmental defects, as well as distinct lateral root growth morphological phenotypes.
  
  
  CONCLUSIONS
  These results suggest that having at least one vegetative profilin gene is essential to viability. Evidence is presented that combinations of independent function, quantitative genetic effects, and functional redundancy have preserved the three vegetative profilin genes in the Arabidopsis lineage.
authors.affiliation: Genetics Department, Davison Life Sciences Building, University of Georgia, Athens, GA, 30602, USA. kjmussar@gmail.com.
authors.forename: Kristofer J
authors.initials: KJ
authors.lastname: Müssar
authors.affiliation: Genetics Department, Davison Life Sciences Building, University of Georgia, Athens, GA, 30602, USA. kandu@uga.edu.
authors.forename: Muthugapatti K
authors.initials: MK
authors.lastname: Kandasamy
authors.affiliation: Genetics Department, Davison Life Sciences Building, University of Georgia, Athens, GA, 30602, USA. emckiney@uga.edu.
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: McKinney
authors.affiliation: Genetics Department, Davison Life Sciences Building, University of Georgia, Athens, GA, 30602, USA. meagher@uga.edu.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Meagher
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D018744:DNA, Plant / Q000235:genetics* / Q000378:metabolism; D055785:Gene Knockdown Techniques; D009154:Mutation; D063246:Organogenesis, Plant; D010641:Phenotype; D051304:Profilins / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference
chemical_list: D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D018744:DNA, Plant; D051304:Profilins; C036483:T-DNA