Nodules formed on the roots of actinorhizal plants as a consequence of nitrogen-fixing symbioses with the actinomycete Frankia appear to result from modification of the developmental pathway that leads to lateral root formation. Presently no information exists about factors that control this developmental switch or, until now, about genes that are differentially expressed as a result of an alte...

Rice tungro spherical virus (RTSV) has an RNA genome of more than 12 kb with various features which classify it as a plant picornavirus. The capsid comprises three coat protein (CP) species, CP1, CP2 and CP3, with predicted molecular masses of 22.5, 22.0 and 33 kDa, respectively, which are cleaved from a polyprotein. In order to obtain information on the properties of these proteins, each was e...

We have investigated mechanisms of dorsal-ventral patterning of neural tissue, using Xenopus ectoderm neuralized by noggin protein. This tissue appears to be patterned dorsoventrally; cp1-1, a gene expressed in the dorsal brain, and etr-1, a gene largely excluded from the dorsal brain, are expressed in separate territories in noggin-treated explants (Knecht, A. K., Good, P. J., Dawid, I. B. and...

LeBrun constructed a scalar-flat Kähler metric on the total space of Chern class −n line bundle O(−n) → CP1. We study moduli spaces of ASD connections on it. It is known that the natural L2-metrics on them are kählerian. We study them when the metric is complete. We give an algorithm to compute their Betti numbers. On the way of the proof, we also show that their homology groups have no torsion...

In this paper, zero modes of fluctuation are dissected around the two species of BPS vortices existing in the critical Higgs phase, where the scalar and vector meson masses are equal, of a gauged U(1) nonlinear CP1-model. If 2πn, n ∈ Z, is the quantized magnetic flux of the two species of BPS vortex solutions, 2n linearly-independent vortex zero modes for each species are found and described. T...

Let Fq be a finite field of q elements, and let Fq[x] be the polynomial ring over Fq. The Möbius function of a nonzero polynomial F ∈ Fq[x] is defined to be μ(F) = (−1)r if F = cP1 · · ·Pr with 0 = c ∈ Fq and P1, . . . , Pr are distinct monic irreducible polynomials, and μ(F) = 0 otherwise. Let Mn ⊂ Fq[x] be the set of monic polynomials of degree n over Fq, which is of size #Mn = qn. For r > 0,...

In these notes we solve a class of Riemann-Hilbert (inverse monodromy) problems with an arbitrary quasi-permutation monodromy group. The solution is given in terms of Szegö kernel on the underlying Riemann surface. In particular, our construction provides a new class of solutions of the Schlesinger system. We present some results on explicit calculation of the corresponding tau-function, and de...

Bacillithiol is produced by many Gram-positive bacteria via a pathway utilizing the enzymes BshA, BshB, and BshC. Here we report the 1.77 Å resolution crystal structure of BshC, the putative cysteine ligase in bacillithiol production. The structure reveals that BshC contains a core Rossmann fold with connecting peptide motifs (CP1 and CP2) and a unique α-helical coiled-coil domain that facilita...

Let Fq be a finite field of q elements, and let Fq[x] be the polynomial ring over Fq. The Möbius function of a nonzero polynomial F ∈ Fq[x] is defined to be μ(F) = (−1)r if F = cP1 · · ·Pr with 0 = c ∈ Fq and P1, . . . , Pr are distinct monic irreducible polynomials, and μ(F) = 0 otherwise. Let Mn ⊂ Fq[x] be the set of monic polynomials of degree n over Fq, which is of size #Mn = qn. For r > 0,...