Characterization of a HeLa cDNA clone encoding the human SII protein, an elongation factor for RNA polymerase II.

We present the cloning and sequence characterization of a HeLa cDNA encoding the SII transcription elongation factor. This cDNA clone is distinct from those previously isolated from a human kidney cDNA library [Yoo et al., Nucleic Acids Res. 19 (1991) 1073-1079]. Southern analysis suggests that more than one gene may exist for SII in the human genome. A comparison of deduced amino acid sequences for SII-related proteins from a variety of eukaryotes demonstrates very high similarity, especially within the C-terminal domain.