article protein expression unclassified drug nonhuman 106 controlled study 105 priority journal 105 Animals 85 animal cell 61 Humans 58 human 55 protein function 45 Mice 42 mouse 40 human cell 38 animal experiment 37 Female 31 female 29 animal tissue 26 enzyme activity 26 messenger RNA 26 signal transduction 26 metabolism 25 rat 22 Rats 20 animal model 20 nucleotide sequence 20 Signal Transduction 19 gene expression 19 Male 18 RNA, Messenger 18