Isolation, sequence and molecular karyotype analysis of the actin gene of Cryptosporidium parvum

Mol Biochem Parasitol. 1992 Jan;50(1):105-13. doi: 10.1016/0166-6851(92)90248-i.


Actin is an ubiquitous and highly conserved microfilament protein which is hypothesized to play a mechanical, force-generating role in the unusual gliding motility of sporozoan zoites and in their active penetration of host cells. We have identified and isolated an actin gene from a Cryptosporidium parvum genomic DNA library using a chicken beta-actin cDNA as an hybridization probe. The nucleotide sequences of two overlapping recombinant clones were identical and the amino acid sequence deduced from the single open reading frame was 85 % identical to the P. falciparum actin I and human gamma-actin proteins. The predicted 42 106-Da Cryptosporidium actin contains 376 amino acids and is encoded by a single-copy gene which contains no introns. The nucleic acid coding sequence is 72% biased to the use of A or T in the third position of codons. Chromosome-sized DNA released from intact C. parvum oocysts was resolved by OFAGE into 5 discrete ethidium bromide-staining DNAs ranging in size from 900 to 1400 kb; the cloned C. parvum actin gene hybridized to a single chromosomal DNA of approximately 1200 kb.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / genetics*
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Blotting, Southern
  • Codon
  • Cryptosporidium parvum / genetics*
  • DNA, Protozoan
  • Karyotyping
  • Molecular Sequence Data
  • Restriction Mapping
  • Sequence Alignment


  • Actins
  • Codon
  • DNA, Protozoan

Associated data

  • GENBANK/M69014