This paper reports on the cloning and characterization of a novel human ribonucleoprotein, RBM8, containing a single RNA binding domain comprising the two RNP-CS and RNP-2 consensus motifs. The protein has 55% identity to a segment of a C. elegans ribonucleoprotein of unknown function. The RBM8 gene shows ubiquitous tissue expression, predominantly as a 0.9 kb transcript. An interesting feature of the RBM8 transcript is an homology of 42% in the 3' untranslated region, in the antisense orientation, to the human gonadotropin-releasing hormone receptor polypeptide. RBM8 maps to human chromosome 14 in the 14q21-q23 region.