High impact information on PFN3/PRF3

• The ability of profilin to regulate actin polymerization and participate directly in signal transduction pathways is discussed in light of the prf1-1 phenotypes [1].
• Analysis of the Arabidopsis genome sequence indicates that, unlike animals and fungi, formins are the only class of conserved profilin-binding PLP proteins in plants [2].
• How profilin uses the ATP hydrolysis that accompanies actin polymerization and whether the acceleration of nucleotide exchange on G-actin by profilin participates in its function in filament assembly are the issues addressed here [3].
• Root hair formation: F-actin-dependent tip growth is initiated by local assembly of profilin-supported F-actin meshworks accumulated within expansin-enriched bulges [4].
• Profilin (PFN) is an ubiquitous, low-M(r), actin-binding protein involved in the organization of the cytoskeleton of eukaryotes including higher plants [5].

Biological context of PFN3/PRF3

• Role of nucleotide exchange and hydrolysis in the function of profilin in action assembly [3].
• Gene trees constructed from amino acid sequence data revealed the presence of two ancient, distinct profilin gene classes in plants [6].
• Profilin plays a role in cell elongation, cell shape maintenance, and flowering in Arabidopsis [5].

Anatomical context of PFN3/PRF3

• Profilin is a ubiquitous eukaryotic protein that regulates the actin cytoskeleton and recently has been identified as a potent allergen in pollen [6].
• All but one of the murine B cell epitopes defined in this work were located on the surface of the profilin molecule in the alpha-helices (10A4 and 3H8) or in the turns (5F2 and 9G4) [7].

Analytical, diagnostic and therapeutic context of PFN3/PRF3

• Immunoblotting of lines expressing a profilin PRF1 3' untranslated region (UTR)-specific construct demonstrated a 77 to 97% reduction in PRF1 protein, but not other profilin isovariants [8].
• The presence of marker molecules such as profilin, the low occurrence of chloroplast-related mRNAs, and the sieve element localization of constituent mRNA using in situ hybridization were consistent with a phloem origin of the sap [9].

References