Abstract

Five cDNAs encoding two α-tubulins(α13 and α15), two β-tubulins(β5 and β5), and one flagellar calmodulin (Cal-1) were cloned from naegleria gruberi NB-1 and their nt sequences were determined. The α13(EMBL number X81049) and β1(EMBL number X81050) contained a complete open reading frame for α-tubulin and β-tubulin, respectively. The other three clones (α15, β5 and Cal-1) had a part of coding region and a 3’ untranslated region of the respective genes. The α13, β1 and Cal-1 had no homologous sequences in the coding regions and in the 3’ untranslated sequences. However, the α13 and β1 shared an eight nucleotide (AATACAAA) sequence in front of the respective initiation codons. The AATACAAA sequence was also found in N. gruberi strain NEG α-tubulin cDNA clone(αpT1) at the same position. Comparison of the α13 to the αpT1 revealed another stretch of identical sequence, which is 30 nts long, in the 5’ untranlated region.

• Keywords: α-tubulin; β-tubline; Calmodulin; cDNA clone; 5' untranslated region; Naegleria gruberi