We have cloned and sequenced a cDNA encoding GTP-binding protein from a fish cell, CHSE-214. The clone was 1493 bp long and contained an open reading frame encoding 364 amino acids. It has the five sequence motifs G1-G5 that are conserved in all GTP-binding proteins. Its amino acid sequences are strikingly different from those of the well-characterized G-proteins. However, sequences closely related to this protein are found in various kinds of species including human, Arabidopsis, Drosophila and archaebacteria, suggesting a novel subfamily within the superfamily of the GTP-binding proteins. Northern analysis indicates that this gene is constitutively expressed at a low level in normal cells but is induced by fish rhabdovirus infection at about 24 h post infection and disappears thereafter. Based on these observations, we propose that this protein represents an evolutionarily conserved novel subfamily of GTP-binding proteins which may play an important role in fish rhabdovirus infection.
Lee, E. H., Kim, H. J., Park, J. J., Choi, J. Y., Cho, W. J., Cha, S. J., … Park, J. W. (1998). Molecular cloning of a novel GTP-binding protein induced in fish cells by rhabdovirus infection. FEBS Letters, 429(3), 407–411. https://doi.org/10.1016/S0014-5793(98)00641-3