An unusual actin-encoding gene in Physarum polycephalum

  • Adam L
  • Laroche A
  • Barden A
 et al. 
  • 2

    Readers

    Mendeley users who have this article in their library.
  • 16

    Citations

    Citations of this article.

Abstract

Actin is one of the most conserved proteins in eukaryotic organisms. In the present work, we cloned and determined the nucleotide sequence of an unusual actin-encoding gene, ardD, from the slime mold, Physarum polycephalum. The ardD gene encodes an ArdD protein containing 367 amino acids (aa) instead of the 375-376 aa found in a typical actin. The nine missing aa are accounted for by deletions of three aa in the first exon, five in the fifth exon and one in the sixth exon. These deletions in the coding sequence were observed in a polymerase chain reaction (PCR)-generated cDNA fragment, which excludes the possibility of a cloning artifact. In addition, ArdD contains numerous aa substitutions distributed throughout the protein. The ArdD aa sequence was compared with published actin sequences. The most identity is seen with the P. polycephalum ArdA, ArdB and ArdC (84%) and Acanthamoeba (82%) actins, while the least identity is found with Tetrahymena actin (67%). The expression of the ardD gene is developmentally regulated. The highest levels of ardD mRNA were found in spherules, less was seen in plasmodia and no detectable transcripts were observed in amoebae. The PCR amplification of an ardD cDNA from spherules confirmed the presence of mRNA in this developmental stage. The aa deletions and substitutions in the predicted ArdD aa sequence make it one of the most distinctive actins known. © 1991.

Author-supplied keywords

  • Gene family
  • gene cloning
  • recombinant DNA
  • slime mold

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Luc Adam

  • André Laroche

  • Anne Barden

  • Gérald Lemieu

  • Dominick Pallotta

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free