Scheid A, Schaal H, Klein M, Gehrmann P; International Conference on AIDS.

Int Conf AIDS. 1993 Jun 6-11; 9: 139 (abstract no. PO-A01-0026).

Institut fur Medizinische Mikrobiologie und Virologie, Henrich-Heine-Universitat Dausseldorf, Germany.

OBJECTIVE: The characterization of the structure of the N-terminal amino acid sequences of gp41 for Env mediated membrane fusion. METHODS: An env-expression vector was constructed that allows mutational analysis within the N-terminus of gp41. Mutations in this location were found to interfere with the function of the RRE and therefore expression vectors were equipped with a second RRE downstream of the env-ORF. Cells were transfected by electroporation and microinjection with a series of deletion mutants of the N-terminus of gp41 and analysed by western blot and syncytia formation for expression of the glycoprotein, as well as cleavage and functionality in cell-cell fusion. RESULTS: The deletion mutants penv-1RRE to penv-7RRE carry a deletion of one to seven codons preceeding the Phe-Leu-Gly motif of gp41. Formation of large syncytia could be observed after electroporation with mutants carrying deletions of up to two residues (penv-1RRE and penv-2RRE). After transfection by microinjection and fluorescent labelling of injected nuclei, small syncytia with as few as two nuclei could be detected also with penv-3RRE and penv-4RRE. Even with this highly sensitive detection method, the capability of syncytium formation was completely lost with deletions of five or more amino acids. Expression and proteolytic processing of mutant glycoproteins were not affected as shown by western blot analysis. Thus the structure of the gp41 N-terminus required for membrane fusing activity extends beyond the Phe-Leu-Gly motif found at the N-terminus of viral membrane fusing proteins of myxo- and paramyxoviruses.

Publication Types:

• Meeting Abstracts

Keywords:

• Amino Acids
• Base Sequence
• Cell Communication
• Cell Fusion
• Genes, env
• Giant Cells
• HIV-1
• Membrane Fusion
• Transfection
• genetics

Other ID:

• 93333454

UI: 102202828

From Meeting Abstracts