title: siRNA silencing of calumenin enhances functional factor IX production.
abstract: To improve production of functional fully gamma-carboxylated recombinant human clotting factor IX (r-hFIX), cell lines stably overexpressing r-hFIX have been engineered to also overexpress proteins of the gamma-carboxylation system. Here we demonstrate that siRNA silencing of calumenin, an inhibitor of the gamma-carboxylation system, enhances production of functional r-hFIX produced by engineered BHK21 cells. The production yield of functional r-hFIX was 80% in engineered cells where calumenin had been silenced 78%. We propose that this high-yield expression system can easily be adapted to overproduce functional forms of all members of the vitamin K-dependent protein family.
authors.affiliation: Department of Internal Medicine, Wake Forest University School of Medicine, Medical Center BLV, Winston-Salem, NC 27157, USA.
authors.forename: Nadeem
authors.initials: N
authors.lastname: Wajih
authors.forename: Susan M
authors.initials: SM
authors.lastname: Hutson
authors.forename: Reidar
authors.initials: R
authors.lastname: Wallin
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D002460:Cell Line; D006224:Cricetinae; D005164:Factor IX / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D005818:Genetic Engineering / Q000379:methods; D006801:Humans; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D002135:Calcium-Binding Proteins; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; D005164:Factor IX