Serine proteases in rodent hippocampus.
Brain serine proteases are implicated in developmental processes, synaptic plasticity, and in disorders including Alzheimer's disease. The spectrum of the major enzymes expressed in brain has not been established previously. We now present a systematic study of the serine proteases expressed in adult rat and mouse hippocampus. Using a combination of techniques including polymerase chain reaction amplification and Northern blotting we show that tissue-type plasminogen activator (t-PA) is the major species represented. Unexpectedly, the next most abundant species were RNK-Met-1, a lymphocyte protease not reported previously in brain, and two new family members, BSP1 (brain serine protease 1) and BSP2. We report full-length sequences of the two new proteases; homologies indicate that these are of tryptic specificity. Although BSP2 is expressed in several brain regions, BSP1 expression is strikingly restricted to hippocampus. Other enzymes represented, but at lower levels, included elastase IV, proteinase 3, complement C2, chymotrypsin B, chymotrypsin-like protein, and Hageman factor. Although thrombin and urokinase-type plasminogen activator were not detected in the primary screen, low level expression was confirmed using specific polymerase chain reaction primers. In contrast, and despite robust expression of t-PA, the usual t-PA substrate plasminogen was not expressed at detectable levels.
Davies
B J
BJ
Center for Genome Research, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh EH9 3JQ, United Kingdom.
Pickard
B S
BS
Steel
M
M
Morris
R G
RG
Lathe
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001923:Brain Chemistry; D015870:Gene Expression; D006624:Hippocampus / Q000201:enzymology*; D017403:In Situ Hybridization; D007610:Kallikreins; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000096:biosynthesis / Q000235:genetics*; D014018:Tissue Distribution; D010959:Tissue Plasminogen Activator / Q000096:biosynthesis / Q000235:genetics
D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D007610:Kallikreins; C485430:Klk8 protein, rat; C114664:Prss19 protein, mouse; C114665:Prss22 protein, mouse; C485431:Prss22 protein, rat; C078432:RNK-Met-1; D012697:Serine Endopeptidases; D010959:Tissue Plasminogen Activator