RNA-binding protein complex. Molecular model of a mitochondrial RNA-binding protein complex (MRP1/MRP2), bound to guide RNA (gRNA) and an RNA tetramer. gRNA is a form of RNA (ribonucleic acid) that controls the process of RNA editing, within the mitochondria of kinetoplastid organisms (a type of protozoa). gRNA binds to the region of mRNA to be edited, and the differences in genetic code between it and the mRNA are copied across. gRNA-binding protein complexes facilitate the binding of gRNA to mRNA by stabilizing both molecules in a state that allows the process to occur.