S. L. Kozak

Cell-surface receptors for gibbon ape leukemia virus and amphotropic murine retrovirus are inducible sodium-dependent phosphate symporters.

Kavanaugh, M P, Miller, D G, Zhang, W, Law, W, Kozak, S L, Kabat, D, ...

Cell surface receptors for gibbon ape leukemia virus (Glvr-1) and murine amphotropic retrovirus (Ram-1) are distinct but related proteins having multiple membrane-spanning regions. Distant homology...

Activation of erythropoietin receptors by Friend viral gp55 and by erythropoietin and down-modulation by the murine Fv-2r resistance gene.

Hoatlin, M E, Kozak, S L, Lilly, F, Chakraborti, A, Kozak, C A, Kabat, D

The leukemogenic membrane glycoprotein (gp55) encoded by Friend spleen focus-forming virus appears to bind to erythropoietin receptors (EpoR) sto stimulate erythroblastosis [Li, J.-P., D'Andrea,...

Deletions in one domain of the Friend virus-encoded membrane glycoprotein overcome host range restrictions for erythroleukemia.

Hoatlin, M E, Ferro, F E, Geib, R W, Fox, M T, Kozak, S L, Kabat, D

Although the Friend virus-encoded membrane glycoprotein (gp55) activates erythropoietin receptors (EpoR) to cause erythroblastosis only in certain inbred strains of mice but not in other species,...

The envelope glycoprotein of an amphotropic murine retrovirus binds specifically to the cellular receptor/phosphate transporter of susceptible species.

Kozak, S L, Siess, D C, Kavanaugh, M P, Miller, A D, Kabat, D

A rat cDNA (rRam-1), which was cloned on the basis that it enables Chinese hamster ovary (CHO) cells to be infected by amphotropic host range murine retroviruses, was recently found to encode a...

Exceptional fusogenicity of Chinese hamster ovary cells with murine retroviruses suggests roles for cellular factor(s) and receptor clusters in the membrane fusion process.

Siess, D C, Kozak, S L, Kabat, D

Chinese hamster ovary (CHO) cells are naturally resistant to infection by amphotropic and ecotropic murine retroviruses, but they become susceptible after expressing corresponding receptors rRAM-1...

Modulation of ecotropic murine retroviruses by N-linked glycosylation of the cell surface receptor/amino acid transporter.

Wang, H, Klamo, E, Kuhmann, S E, Kozak, S L, Kavanaugh, M P, Kabat, D

The cell surface receptor for ecotropic host-range (infection limited to mice or rats) murine leukemia viruses (MuLVs) is the widely expressed system y+ transporter for cationic amino acids (CAT-1)....

CD4, CXCR-4, and CCR-5 dependencies for infections by primary patient and laboratory-adapted isolates of human immunodeficiency virus type 1.

Kozak, S L, Platt, E J, Madani, N, Ferro, F E, Peden, K, Kabat, D

We have used a focal infectivity method to quantitatively analyze the CD4, CXCR-4, and CCR-5 dependencies for infections by diverse primary patient (PR) and laboratory-adapted (LA) isolates of human...

Infectious properties of human immunodeficiency virus type 1 mutants with distinct affinities for the CD4 receptor.

Platt, E J, Madani, N, Kozak, S L, Kabat, D

Recent evidence suggests that primary patient isolates of T-cell-tropic human immunodeficiency virus type 1 (HIV-1 ) have lower affinities for CD4 than their laboratory-adapted derivatives, that this...

Polymorphisms in the CCR5 genes of African green monkeys and mice implicate specific amino acids in infections by simian and human immunodeficiency viruses.

Kuhmann, S E, Platt, E J, Kozak, S L, Kabat, D

CCR5, a receptor for the CC chemokines RANTES, Mip1alpha, and Mip1beta, has been identified as a coreceptor for infections by macrophage-tropic isolates of human immunodeficiency virus type 1...

Differences in CD4 dependence for infectivity of laboratory-adapted and primary patient isolates of human immunodeficiency virus type 1.

Kabat, D, Kozak, S L, Wehrly, K, Chesebro, B

CD4 is known to be an important receptor for human immunodeficiency virus type 1 (HIV-1) infection of T lymphocytes and macrophages. However, the limiting steps in CD4-dependent HIV-1 infections in...

A Friend virus mutant encodes a small glycoprotein that causes erythroleukemia.

Hoatlin, M E, Ferro, F E, Kozak, S L, Kabat, D

The Pvu delta mutant of Friend spleen focus-forming virus encodes the smallest env glycoprotein (apparent M(r), 41,000) known to activate erythropoietin receptors. In vivo, Pvu delta causes...

A Friend virus mutant that overcomes Fv-2rr host resistance encodes a small glycoprotein that dimerizes, is processed to cell surfaces, and specifically activates erythropoietin receptors.

Kozak, S L, Hoatlin, M E, Ferro, F E, Majumdar, M K, Geib, R W, Fox, M T, ...

The env gene of Friend spleen focus-forming virus (SFFV) encodes a membrane glycoprotein (gp55) that is inefficiently (3 to 5%) processed from the rough endoplasmic reticulum to form a larger dimeric...

The Sfpi-1 proviral integration site of Friend erythroleukemia encodes the ets-related transcription factor Pu.1.

Paul, R, Schuetze, S, Kozak, S L, Kozak, C A, Kabat, D

Previous studies identified a common site (Sfpi-1) for proviral integration in immortalized Friend erythroleukemias. cDNAs corresponding to a 1.5-kb Sfpi-1 mRNA were isolated and sequenced. These...

Ping-pong amplification of a retroviral vector achieves high-level gene expression: human growth hormone production.

Kozak, S L, Kabat, D

Retroviral vectors offer major advantages for gene transfer studies but have not been useful for producing proteins in large quantities. This deficiency has resulted in part from interference to...

A common site for immortalizing proviral integrations in Friend erythroleukemia: molecular cloning and characterization.

Paul, R, Schuetze, S, Kozak, S L, Kabat, D

By using a tagged derivative of Friend spleen focus-forming virus, we previously obtained evidence that proviral integration(s) in the host genome can cause erythroblast immortality by abrogating the...

Overcoming interference to retroviral superinfection results in amplified expression and transmission of cloned genes.

Bestwick, R K, Kozak, S L, Kabat, D

A procedure is described for stably expressing cloned genes at high levels in vertebrate cells and for obtaining these genes in high-titer virus preparations. The process uses retroviral vectors and...

Cell-surface receptors for gibbon ape leukemia virus and amphotropic murine retrovirus are inducible sodium-dependent phosphate symporters.

Kavanaugh, M P, Miller, D G, Zhang, W, Law, W, Kozak, S L, Kabat, D, ...

Cell surface receptors for gibbon ape leukemia virus (Glvr-1) and murine amphotropic retrovirus (Ram-1) are distinct but related proteins having multiple membrane-spanning regions. Distant homology...

Activation of erythropoietin receptors by Friend viral gp55 and by erythropoietin and down-modulation by the murine Fv-2r resistance gene.

Hoatlin, M E, Kozak, S L, Lilly, F, Chakraborti, A, Kozak, C A, Kabat, D

The leukemogenic membrane glycoprotein (gp55) encoded by Friend spleen focus-forming virus appears to bind to erythropoietin receptors (EpoR) sto stimulate erythroblastosis [Li, J.-P., D'Andrea,...

Deletions in one domain of the Friend virus-encoded membrane glycoprotein overcome host range restrictions for erythroleukemia.

Hoatlin, M E, Ferro, F E, Geib, R W, Fox, M T, Kozak, S L, Kabat, D

Although the Friend virus-encoded membrane glycoprotein (gp55) activates erythropoietin receptors (EpoR) to cause erythroblastosis only in certain inbred strains of mice but not in other species,...

The envelope glycoprotein of an amphotropic murine retrovirus binds specifically to the cellular receptor/phosphate transporter of susceptible species.

Kozak, S L, Siess, D C, Kavanaugh, M P, Miller, A D, Kabat, D

A rat cDNA (rRam-1), which was cloned on the basis that it enables Chinese hamster ovary (CHO) cells to be infected by amphotropic host range murine retroviruses, was recently found to encode a...

Exceptional fusogenicity of Chinese hamster ovary cells with murine retroviruses suggests roles for cellular factor(s) and receptor clusters in the membrane fusion process.

Siess, D C, Kozak, S L, Kabat, D

Chinese hamster ovary (CHO) cells are naturally resistant to infection by amphotropic and ecotropic murine retroviruses, but they become susceptible after expressing corresponding receptors rRAM-1...

Modulation of ecotropic murine retroviruses by N-linked glycosylation of the cell surface receptor/amino acid transporter.

Wang, H, Klamo, E, Kuhmann, S E, Kozak, S L, Kavanaugh, M P, Kabat, D

The cell surface receptor for ecotropic host-range (infection limited to mice or rats) murine leukemia viruses (MuLVs) is the widely expressed system y+ transporter for cationic amino acids (CAT-1)....

CD4, CXCR-4, and CCR-5 dependencies for infections by primary patient and laboratory-adapted isolates of human immunodeficiency virus type 1.

Kozak, S L, Platt, E J, Madani, N, Ferro, F E, Peden, K, Kabat, D

We have used a focal infectivity method to quantitatively analyze the CD4, CXCR-4, and CCR-5 dependencies for infections by diverse primary patient (PR) and laboratory-adapted (LA) isolates of human...

Infectious properties of human immunodeficiency virus type 1 mutants with distinct affinities for the CD4 receptor.

Platt, E J, Madani, N, Kozak, S L, Kabat, D

Recent evidence suggests that primary patient isolates of T-cell-tropic human immunodeficiency virus type 1 (HIV-1 ) have lower affinities for CD4 than their laboratory-adapted derivatives, that this...

Polymorphisms in the CCR5 genes of African green monkeys and mice implicate specific amino acids in infections by simian and human immunodeficiency viruses.

Kuhmann, S E, Platt, E J, Kozak, S L, Kabat, D

CCR5, a receptor for the CC chemokines RANTES, Mip1alpha, and Mip1beta, has been identified as a coreceptor for infections by macrophage-tropic isolates of human immunodeficiency virus type 1...

Differences in CD4 dependence for infectivity of laboratory-adapted and primary patient isolates of human immunodeficiency virus type 1.

Kabat, D, Kozak, S L, Wehrly, K, Chesebro, B

CD4 is known to be an important receptor for human immunodeficiency virus type 1 (HIV-1) infection of T lymphocytes and macrophages. However, the limiting steps in CD4-dependent HIV-1 infections in...

A Friend virus mutant encodes a small glycoprotein that causes erythroleukemia.

Hoatlin, M E, Ferro, F E, Kozak, S L, Kabat, D

The Pvu delta mutant of Friend spleen focus-forming virus encodes the smallest env glycoprotein (apparent M(r), 41,000) known to activate erythropoietin receptors. In vivo, Pvu delta causes...

A Friend virus mutant that overcomes Fv-2rr host resistance encodes a small glycoprotein that dimerizes, is processed to cell surfaces, and specifically activates erythropoietin receptors.

Kozak, S L, Hoatlin, M E, Ferro, F E, Majumdar, M K, Geib, R W, Fox, M T, ...

The env gene of Friend spleen focus-forming virus (SFFV) encodes a membrane glycoprotein (gp55) that is inefficiently (3 to 5%) processed from the rough endoplasmic reticulum to form a larger dimeric...

The Sfpi-1 proviral integration site of Friend erythroleukemia encodes the ets-related transcription factor Pu.1.

Paul, R, Schuetze, S, Kozak, S L, Kozak, C A, Kabat, D

Previous studies identified a common site (Sfpi-1) for proviral integration in immortalized Friend erythroleukemias. cDNAs corresponding to a 1.5-kb Sfpi-1 mRNA were isolated and sequenced. These...

Ping-pong amplification of a retroviral vector achieves high-level gene expression: human growth hormone production.

Kozak, S L, Kabat, D

Retroviral vectors offer major advantages for gene transfer studies but have not been useful for producing proteins in large quantities. This deficiency has resulted in part from interference to...

A common site for immortalizing proviral integrations in Friend erythroleukemia: molecular cloning and characterization.

Paul, R, Schuetze, S, Kozak, S L, Kabat, D

By using a tagged derivative of Friend spleen focus-forming virus, we previously obtained evidence that proviral integration(s) in the host genome can cause erythroblast immortality by abrogating the...

Overcoming interference to retroviral superinfection results in amplified expression and transmission of cloned genes.

Bestwick, R K, Kozak, S L, Kabat, D

A procedure is described for stably expressing cloned genes at high levels in vertebrate cells and for obtaining these genes in high-titer virus preparations. The process uses retroviral vectors and...