A new grand unified model based on the product group SU(5) × SU(5) is presented. The product GUT is broken to SU(3)c × SU(2)1 × SU(2)2 × U(1)Y , by an odd number of link fields acquiring suitable vacuum expectation values. The resulting SU(5) gauge anomalies are canceled by endpoint fields that are identified as the ordinary matter and Higgs fields of the MSSM. Doublet-triplet splitting is auto...

The infrared behavior of gluon and ghost propagators in Yang-Mills gauge theories is of central importance for the understanding of confinement in QCD. While analytic studies using Schwinger-Dyson equations predict the same infrared exponents for the SU(2) and SU(3) gauge groups, lattice simulations usually assume that the two cases are different, although their qualitative infrared features ma...

A new tobacco (Nicotiana tabacum) aurea mutant was isolated from the progeny of a selfed variegated tobacco plant. The new mutant is termed Su/su var. Aurea. If the mutant is selfed, the seeds obtained give rise to four types of plants: green seedlings which correspond to the wild type; yellow-green seedlings which correspond to the earlier described Su/su; yellow seedlings which correspond to ...

The seemingly disparate notions of chiral color and quark-lepton nonuniversality are combined, and shown to be essential to each other as part of an underlying (and unifying) larger symmetry, i.e. supersymmetric SU(3). Both phenomena are accessible experimentally at the TeV energy scale. In the Standard Model of quarks and leptons, the electric charge has two components, i.e. Q = I3L + 1 2 Y, (...

Compact chromatin structure, induction of gene silencing in position-effect variegation (PEV), and crossing-over suppression are typical features of heterochromatin. To identify genes affecting crossing-over suppression by heterochromatin we tested PEV suppressor mutations for their effects on crossing over in pericentromeric regions of Drosophila autosomes. From the 46 mutations (28 loci) stud...

Suppressor of Hairy-wing [Su(Hw)] is a DNA-binding factor required for gypsy insulator function and female germline development in Drosophila. The insulator function of the gypsy retrotransposon depends on Su(Hw) binding to clustered Su(Hw) binding sites (SBSs) and recruitment of the insulator proteins Centrosomal Protein 190 kD (CP190) and Modifier of mdg4 67.2 kD (Mod67.2). By contrast, the S...

Suppressor of Hairless (Su(H)) activity is zygotically required in larval imaginal discs for the singling out of adult sense organ precursor (SOP) cells: loss of Su(H) function results in too many proneural cluster cells adopting the SOP fate, while overexpression of the Su(H) protein prevents SOP specification. Su(H) null mutant alleles are recessive lethal at the late larval and early pupal s...

The Su(var)3-7 protein is essential for fly viability, and several lines of evidence support its key importance in heterochromatin formation: it binds to pericentric heterochromatin, it potently suppresses variegation and it interacts with HP1. However, the mode of action of Su(var)3-7 is poorly understood. Here we investigate in vivo the consequences of increased Su(var)3-7 expression on fly v...

Throughout the animal kingdom, the Notch signalling pathway allows cells to acquire diversified cell fates. Notch signals are translated into activation of Notch target genes by CSL transcription factors. In the absence of Notch signals, CSL together with co-repressors functions as a transcriptional repressor. In Drosophila, repression of Notch target genes involves the CSL homologue Suppressor...

The form of the most general orbifold breaking of gauge, global and supersymmetries with a single extra dimension is given. In certain theories the Higgs boson mass is ultraviolet finite due to an unbroken local supersymmetry, which is explicitly exhibited. We construct: a 1 parameter SU(3)×SU(2)×U(1) theory with 1 bulk Higgs hypermultiplet, a 2 parameter SU(3)×SU(2)×U(1) theory with 2 bulk Hig...