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C S Kumar

Publications and source records attributed to C S Kumar.

22 records · Page 2Linked to original sources
PubMed1990

Molecular genetic markers spanning mouse chromosome 10.

Somatic cell hybrids, recombinant inbred (RI) strains, and progeny of an intersubspecific backcross were typed by Southern blot analysis to prepare a linkage map of mouse chromosome 10. The seven genetic markers in this map, four of which had not previously been positioned, include genes involved in oncogenesis (Gli, Myb, Tra-1), proviral integration (Emv-25), and immune responses (Ifg, Ifgr, Pfp). The linkage map spans much of the chromosome and covers a region of the mouse genome with few molecular markers. The gene order established here demonstrates that the genes for murine interferon-gamma (Ifg) and its receptor (Ifgr) are at opposite ends of the chromosome and that Ifgr and the Myb oncogene are closely linked, a factor that may be related to their joint transcriptional enhancement in some plasmacytoid lymphosarcomas.

Animals↗
PubMed1989

Molecular characterization of the murine interferon gamma receptor cDNA.

Interferon gamma receptors (IFN-gamma R) exhibit remarkable species specificity. In order to understand the basis for this phenomenon, we have isolated a recombinant cDNA clone corresponding to the mouse (Mu) IFN-gamma R. Microinjection of the mRNA synthesized in vitro corresponding to the cloned cDNA into Xenopus laevis oocytes resulted in the synthesis of a protein that specifically binds Mu-IFN-gamma. Analysis of murine genomic and RNA blots with the cDNA probe indicates the presence of a single gene and a single mRNA species of about 2300 bases. Sequence analysis of the cDNA encoding the Mu-IFN-gamma R and comparison with the corresponding human IFN-gamma R sequence shows about 68% conservation of the extracellular domains and 51% conservation of the cytoplasmic domains at the nucleotide level. The results indicate that, as expected, the sequence of the receptor confers species specificity for the binding of IFN-gamma to the cell surface receptor. Moreover, it was previously shown that a human factor is required in addition to the receptor for the human IFN-gamma to function in hamster or mouse cells (Jung, V., Rashidbaigi, A., Jones, C., Tischfield, J.A., Shows, T.B., and Pestka, S. (1987) Proc. Natl. Acad. Sci. U.S.A. 84, 4151-4155). These results suggest an explanation for the second species-specific event required for function of the human receptor in mouse or hamster cells in that the intracellular domains are significantly different and thus cannot interact with the corresponding heterologous factor.

Amino Acid Sequence↗
PubMed1988

Expression of the murine interferon gamma receptor in Xenopus laevis oocytes.

This study describes the isolation of mRNA for the murine interferon gamma receptor and its expression in frog oocytes. The binding properties and apparent molecular weight of the murine interferon gamma receptor protein synthesized in frog oocytes is similar to that found on mouse cells. This is the first report of a functional receptor for a polypeptide ligand (interferon gamma) expressed in and directly assayed on frog oocytes.

Animals↗