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<jats:p> Induction of apoptosis by oncogenes like c- <jats:italic>myc</jats:italic> may be important in restraining the emergence of neoplasia. However, the mechanism by which c- <jats:italic>myc</jats:italic> induces apoptosis is unknown. CD95 (also termed Fas or APO-1) is a cell surface transmembrane receptor of the tumor necrosis factor receptor family that activates an intrinsic apoptotic suicide program in cells upon binding either its ligand CD95L or antibody. c- <jats:italic>myc</jats:italic> –induced apoptosis was shown to require interaction on the cell surface between CD95 and its ligand. c-Myc acts downstream of the CD95 receptor by sensitizing cells to the CD95 death signal. Moreover, IGF-I signaling and Bcl-2 suppress c- <jats:italic>myc</jats:italic> –induced apoptosis by also acting downstream of CD95. These findings link two apoptotic pathways previously thought to be independent and establish the dependency of Myc on CD95 signaling for its killing activity. </jats:p>

<jats:p> The Janus family of tyrosine kinases (JAK) plays an essential role in development and in coupling cytokine receptors to downstream intracellular signaling events. A t(9;12)(p24;p13) chromosomal translocation in a T cell childhood acute lymphoblastic leukemia patient was characterized and shown to fuse the 3′ portion of <jats:italic>JAK2</jats:italic> to the 5′ region of <jats:italic>TEL</jats:italic> , a gene encoding a member of the ETS transcription factor family. The TEL-JAK2 fusion protein includes the catalytic domain of JAK2 and the TEL-specific oligomerization domain. TEL-induced oligomerization of TEL-JAK2 resulted in the constitutive activation of its tyrosine kinase activity and conferred cytokine-independent proliferation to the interleukin-3–dependent Ba/F3 hematopoietic cell line. </jats:p>

<jats:p> The emergence of agriculture in the Near East also involved the domestication of einkorn wheat. Phylogenetic analysis that was based on the allelic frequency at 288 amplified fragment length polymorphism molecular marker loci indicates that a wild group of <jats:italic>Triticum monococcum boeoticum</jats:italic> lines from the Karacadağ mountains (southeast Turkey) is the likely progenitor of cultivated einkorn varieties. Evidence from archeological excavations of early agricultural settlements nearby supports the conclusion that domestication of einkorn wheat began near the Karacadağmountains. </jats:p>

<jats:p> The gene responsible for autosomal dominant, fully penetrant, nonsyndromic sensorineural progressive hearing loss in a large Costa Rican kindred was previously localized to chromosome 5q31 and named <jats:italic>DFNA1</jats:italic> . Deafness in the family is associated with a protein-truncating mutation in a human homolog of the <jats:italic>Drosophila</jats:italic> gene <jats:italic>diaphanous</jats:italic> . The truncation is caused by a single nucleotide substitution in a splice donor, leading to a four–base pair insertion in messenger RNA and a frameshift. The diaphanous protein is a profilin ligand and target of Rho that regulates polymerization of actin, the major component of the cytoskeleton of hair cells of the inner ear. </jats:p>

<jats:p> The wild-type <jats:italic>Caenorhabditis elegans</jats:italic> nematode ages rapidly, undergoing development, senescence, and death in less than 3 weeks. In contrast, mutants with reduced activity of the gene <jats:italic>daf-2,</jats:italic> a homolog of the insulin and insulin-like growth factor receptors, age more slowly than normal and live more than twice as long. These mutants are active and fully fertile and have normal metabolic rates. The life-span extension caused by <jats:italic>daf-2</jats:italic> mutations requires the activity of the gene <jats:italic>daf-16. daf-16</jats:italic> appears to play a unique role in life-span regulation and encodes a member of the hepatocyte nuclear factor 3 (HNF-3)/forkhead family of transcriptional regulators. In humans, insulin down-regulates the expression of certain genes by antagonizing the activity of HNF-3, raising the possibility that aspects of this regulatory system have been conserved. </jats:p>