Sequence of a complete murine cDNA reflecting an S phase-prevalent transcript encoding a protein with two types of...

Differential screening of a murine RNA-based lambda gt10 cDNA library with cell cycle phase-specific probes released a cDNA clone (lambda GS1) to a mRNA (1.8 kb) which is prevalent in the S phase of the cell cycle. The nucleotide sequence of the cDNA predicts a protein (RNPS1, 41 x 10(3) M(r) with two nucleic acid-binding domains separated by a proline-rich spacer. The N-terminal nucleic acid binding domain, about 80 amino acid residues in length, meets the requirements of an RNA recognition motif (RRM) including a perfect 'RNP-1 octamer'. The C-terminal nucleic acid binding domain spanning over 26 amino acid residues is prominent because it comprises three copies of the RRRS peptide. Domains of the latter type are considered to be involved in RNA and DNA-binding because comprised in many RNA and DNA-binding proteins.