Cloning and characterization of an unusual elongation factor-1 alpha cDNA from Entamoeba histolytica.
The coding sequence deduced from two overlapping cDNA inserts obtained from a pathogenic strain of Entamoeba histolytica revealed a striking homology (greater than 85%) with elongation factor EF-1 alpha from Saccharomyces cerevisiae and Artemia salina. The deduced amino acid sequence predicted a size of 49 kDa, and antibodies raised against the S. cerevisiae EF-1 alpha cross-reacted with an amoebic protein of similar size (45-47 kDa). Sequence analysis of the cDNA revealed that the 5' untranslated region contained a stretch of 190 nucleotides which was perfectly complementary to a segment of the 3' terminal coding region situated 1015 bases downstream of the methionine initiation codon. Electron microscopy of self-renatured cDNA confirmed the potential of such molecules to form a stem-loop secondary structure. The presence of the complementary sequences was confirmed at the genomic level by sequence analysis of polymerase chain reaction-amplified segments which span both the 3' and 5' terminal complementary regions. Comparison of the deduced amino acid sequence of E. histolytica EF-1 alpha with Ef-Tu from Escherichia coli and EF-1 alpha from different sources, suggested that the major functional domains of the protein are located within the loop structure.
De Meester
F
F
MacArthur Center for Molecular Biology of Parasitic Diseases, Weizmann Institute of Science, Rehovot, Israel.
Bracha
R
R
Huber
M
M
Keren
Z
Z
Rozenblatt
S
S
Mirelman
D
D
D000595:Amino Acid Sequence; D000818:Animals; D001156:Artemia / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D016054:DNA, Protozoan / Q000235:genetics*; D004748:Entamoeba histolytica / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid
D016054:DNA, Protozoan; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors; D004247:DNA