Immune-associated nucleotide-1 (IAN-1) is a thymic selection marker and defines a novel gene family conserved in plants.

Positive selection of thymocytes is a complex and crucial event in T cell development that is characterized by cell death rescue, commitment toward the helper or cytotoxic lineage, and functional maturation of thymocytes bearing an appropriate TCR. To search for novel genes involved in this process, we compared gene expression patterns in positively selected thymocytes and their immediate progenitors in mice using the differential display technique. This approach lead to the identification of a novel gene, mIAN-1 (murine immune-associated nucleotide-1), that is switched on upon positive selection and predominantly expressed in the lymphoid system.

Cloning and functional expression of the human histamine H3 receptor.

Histamine regulates neurotransmitter release in the central and peripheral nervous systems through H3 presynaptic receptors. The existence of the histamine H3 receptor was demonstrated pharmacologically 15 years ago, yet despite intensive efforts, its molecular identity has remained elusive. As part of a directed effort to discover novel G protein-coupled receptors through homology searching of expressed sequence tag databases, we identified a partial clone (GPCR97) that had significant homology to biogenic amine receptors.

Cloning differentially expressed mRNAs.

Differential gene expression occurs in the process of development, maintenance, injury, and death of unicellular as well as complex organisms. Differentially expressed genes are usually identified by comparing steady-state mRNA concentrations. Electronic subtraction (ES), subtractive hybridization (SH), and differential display (DD) are methods commonly used for this purpose.

Secretion of thermostable DNA polymerase using a novel baculovirus vector.

Baculovirus-mediated expression has become a powerful tool for the high yield production of functionally active recombinant proteins. In order to further enhance the utility of this expression system, we constructed versatile transfer vectors that facilitate the secretion of recombinant proteins from host insect cells by inserting functional secretory leader sequences down-stream of the polyhedrin promoter. In-frame insertion of cDNA sequences results in the synthesis of fusion proteins containing a heterologous signal sequence which directs the recombinant protein to the secretory pathway.