The FIP1 gene encodes a component of a yeast pre-mRNA polyadenylation factor that directly interacts with poly(A) polymerase

Cell. 1995 May 5;81(3):379-89. doi: 10.1016/0092-8674(95)90391-7.


We have identified an essential gene, called FIP1, encoding a 327 amino acid protein interacting with yeast poly(A) polymerase (PAP1) in the two-hybrid assay. Recombinant FIP1 protein forms a 1:1 complex with PAP1 in vitro. At 37 degrees C, a thermosensitive allele of FIP1 shows a shortening of poly(A) tails and a decrease in the steady-state level of actin transcripts. When assayed for 3'-end processing in vitro, fip1 mutant extracts exhibit normal cleavage activity, but fail to polyadenylate the upstream cleavage product. Polyadenylation activity is restored by adding polyadenylation factor I (PF I). Antibodies directed against FIP1 specifically recognize a polypeptide in these fractions. Coimmunoprecipitation experiments reveal that RNA14, a subunit of cleavage factor I (CF I), directly interacts with FIP1, but not with PAP1. We propose a model in which PF I tethers PAP1 to CF I, thereby conferring specificity to poly(A) polymerase for pre-mRNA substrates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / genetics
  • Amino Acid Sequence
  • Base Sequence
  • Cloning, Molecular
  • Genes, Fungal / genetics
  • Models, Genetic
  • Molecular Sequence Data
  • Mutagenesis
  • Pancreatitis-Associated Proteins
  • Poly A / analysis
  • Polynucleotide Adenylyltransferase / metabolism*
  • Protein Binding
  • Protein Denaturation
  • RNA Precursors / metabolism*
  • RNA Processing, Post-Transcriptional
  • RNA, Messenger / analysis
  • RNA, Messenger / metabolism*
  • RNA-Binding Proteins / genetics*
  • RNA-Binding Proteins / metabolism
  • Recombinant Fusion Proteins / metabolism
  • Regulatory Sequences, Nucleic Acid
  • Saccharomyces cerevisiae / genetics*
  • Sequence Analysis, DNA
  • mRNA Cleavage and Polyadenylation Factors


  • Actins
  • Pancreatitis-Associated Proteins
  • REG3A protein, human
  • RNA Precursors
  • RNA, Messenger
  • RNA-Binding Proteins
  • Recombinant Fusion Proteins
  • mRNA Cleavage and Polyadenylation Factors
  • Poly A
  • Polynucleotide Adenylyltransferase

Associated data

  • GENBANK/X83796