PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 12130552-7 2002 In contrast, mutation of this tryptophan to alanine in mR2 decreased the rate of internalization and inhibited basal signaling activity. Tryptophan 30-40 ribonucleotide reductase M2 Mus musculus 55-58