title: Histidylated lipid-modified Sendai viral envelopes mediate enhanced membrane fusion and potentiate targeted gene delivery.
abstract: Recent studies have demonstrated that covalent grafting of a single histidine residue into a twin-chain aliphatic hydrocarbon compound enhances its endosome-disrupting properties and thereby generates an excellent DNA transfection system. Significant increase in gene delivery efficiencies has thus been obtained by using endosome-disrupting multiple histidine functionalities in the molecular architecture of various cationic polymers. To take advantage of this unique feature, we have incorporated L-histidine (N,N-di-n-hexadecylamine) ethylamide (L(H)) in the membrane of hepatocyte-specific Sendai virosomes containing only the fusion protein (F-virosomes (Process for Producing a Targeted Gene (Sarkar, D. P., Ramani, K., Bora, R. S., Kumar, M., and Tyagi, S. K. (November 4, 1997) U. S. Patent 5,683,866))). Such L(H)-modified virosomal envelopes were four times more (p < 0.001) active in terms of fusion with its target cell membrane. On the other hand, the presence of L(H) in reconstituted influenza and vesicular stomatitis virus envelopes failed to enhance spike glycoprotein-induced membrane fusion with host cell membrane. Circular dichroism and limited proteolysis experiments with F-virosomes indicated that the presence of L(H) leads to conformational changes in the F protein. The molecular mechanism associated with the increased membrane fusion induced by L(H) has been addressed in the light of fusion-competent conformational change in F protein. Such enhancement of fusion resulted in a highly efficient gene delivery system specific for liver cells in culture and in whole animals.
authors.affiliation: Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, USA.
authors.forename: Santosh K
authors.initials: SK
authors.lastname: Verma
authors.forename: Prashant
authors.initials: P
authors.lastname: Mani
authors.forename: Nishi Raj
authors.initials: NR
authors.lastname: Sharma
authors.forename: Anuja
authors.initials: A
authors.lastname: Krishnan
authors.forename: Valluripalli Vinod
authors.initials: VV
authors.lastname: Kumar
authors.forename: Bathula Surendar
authors.initials: BS
authors.lastname: Reddy
authors.forename: Arabinda
authors.initials: A
authors.lastname: Chaudhuri
authors.forename: Rajendra P
authors.initials: RP
authors.lastname: Roy
authors.forename: Debi P
authors.initials: DP
authors.lastname: Sarkar
mesh_terms: D000818:Animals; D002412:Cations / Q000737:chemistry; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D011992:Endosomes; D005260:Female; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000737:chemistry / Q000378:metabolism; D006367:HeLa Cells; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism / Q000821:virology; D006639:Histidine / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D007700:Kinetics; D008055:Lipids / Q000737:chemistry; D008099:Liver / Q000166:cytology; D008156:Luciferases / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D011108:Polymers / Q000737:chemistry; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029082:Sendai virus / Q000378:metabolism*; D013997:Time Factors; D014162:Transfection; D014759:Viral Envelope Proteins / Q000737:chemistry*
chemical_list: D002412:Cations; D008055:Lipids; D011108:Polymers; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D014759:Viral Envelope Proteins; D049452:Green Fluorescent Proteins; D006639:Histidine; D004247:DNA; D008156:Luciferases