Characterization of Pactolus: transcription and function

Pactolus is a transmembrane protein found mainly on maturing to mature neutrophils and is homologous to ? integrin subunits. The majority of Pactolus is sequestered inside the cell until the neutrophil is activated or undergoes apoptosis. The gene structure of pactolus was determined in order to create a Pactolus deficient mouse. At the start of this thesis, Pactolus function was unknown, and the Pactolus deficient mouse proved to be instrumental in elucidating Pactolus function. Pactolus was not detected to have any intracellular signaling or in vivo functions, but in an in vitro assay mixing wild type or Pactolus deficient neutrophils with macrophages, Pactolus function was discovered. Pactolus appears to specifically interact with a macrophage receptor to facilitate apoptotic neutrophil phagocytosis by the macrophage and to downregulate macrophage TNF-? production. In a second project, to elucidate the tissue specific transcriptional control of the pactolus gene, the pactolus promoter was analyzed utilizing EMSA protocols. These data suggest a role for PU.1 and NF-k;B in pactolus gene regulation.