Search for a Caenorhabditis elegans FMR1 homologue: Identification of a new putative RNA-binding protein (PRP-1) that hybridizes to the mouse FMR1 double K homology domain

A mixed stage lambda gt10 Caenorhabditis elegans cDNA library was screened with a probe derived by polymerase chain reaction from the double K homolog y (KH) domain of mouse FMR1 cDNA, a region that is highly conserved in the human, mouse, chicken, and frog FMR1 proteins. Four positively hybridizing cDNAs were cloned and characterized by sequencing, The overlapping sequence s map to cosmid R119 from C. elegans linkage group (chromosome) I, and enco de a novel proline-, polyglutamine-, and RGG box-rich putative RNA-binding protein. While the cDNA has two regions with similarity to the mouse double KH domain probe at the nucleotide level, there is no significant similarit y of the amino acid sequence with human FMR1, FXR1 or FXR2, nor with KH ami no acid motifs, The Rile protein, therefore, does not represent an FMR1 hom ologue. (C) 1999 Wiley-Liss, Inc.