LARP1

Function

All LARP proteins, including human LARP, contain 2 conserved regions. The first conserved region shares homology with La proteins (called the La motif, see SSB) whereas the second conserved region (called the LARP1 motif) is restricted to LARP proteins. Mouse Larp1 is expressed in dorsal root ganglia and spinal cord, as well as in developing organs characterized by epithelial-mesenchymal interactions.

LARP-1 appears to bind mRNA in vitro via both the La motif and the LARP1 domain. LARP-1 also appears to down-regulate the Ras-MAPK pathway. LARP-1 protein colocalizes with P bodies, which function in RNA degradation. We suggest that LARP-1 functions in P-bodies to attenuate the abundance of conserved Ras-MAPK mRNAs. The cluster of LARP-1 homologs may function to control the expression of key developmental regulators.