Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher.
Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?
Some links on this page may take you to non-federal websites. Their policies may differ from this site.
-
We study the moduli stack of degree 0 0 semistable G G -bundles on an irreducible curve E E of arithmetic genus 1 1 , where G G is a connected reductive group in arbitrary characteristic. Our main result describes a partition of this stack indexed by a certain family of connected reductive subgroups H H of G G (the E E -pseudo-Levi subgroups), where each stratum is computed in terms of H H -bundles together with the action of the relative Weyl group. We show that this result is equivalent to a JordanâChevalley theorem for such bundles equipped with a framing at a fixed basepoint. In the case where E E has a single cusp (respectively, node), this gives a new proof of the JordanâChevalley theorem for the Lie algebra g \mathfrak {g} (respectively, algebraic group G G ). We also provide a Tannakian description of these moduli stacks and use it to show that if E E is not a supersingular elliptic curve, the moduli of framed unipotent bundles on E E are equivariantly isomorphic to the unipotent cone in G G . Finally, we classify the E E -pseudo-Levi subgroups using the Borelâde Siebenthal algorithm, and compute some explicit examples.more » « less
-
Summary Despite of important functions of strigolactones (SLs) and karrikins (KARs) in plant development, plantâparasite and plantâfungi interactions, their roles in soybeanârhizobia interaction remain elusive. SL/KAR signaling genes
GmMAX2a, GmD14s, andGmKAIs are activated by rhizobia infection. GmMAX2a restoredatmax2 root hair defects and soybean root hairs were changed inGmMAX2a overexpression (GmMAX2a âOE ) or knockdown (GmMAX2a âKD ) mutants.GmMAX2a âKD gave fewer, whereasGmMAX2a âOE produced more nodules than GUS hairy roots. Mutation ofGmMAX2a in itsKD orOE transgenic hairy roots affected the rhizobia infectionâinduced increases in early nodulation gene expression. Both mutant hairy roots also displayed the altered auxin, jasmonate and abscisic acid levels, as further verified by transcriptomic analyses of their synthetic genes. Overexpression of an auxin synthetic geneGmYUC2a also affected SL and KAR signaling genes. GmMAX2a physically interacted with SL/KAR receptors GmD14s, GmKAIs, and GmD14Ls with different binding affinities, depending on variations in the critical amino acids, forming active D14/KAIâSCFMAX2complexes. The knockdown mutant roots of the noduleâspecifically expressingGmKAI s andGmD14L s gave fewer nodules, with altered expression of several early nodulation genes. The expression levels ofGmKAI s, andGmD14L s were markedly changed inGmMAX2a mutant roots, so did their target repressor genesGmD53 s andGmSMAX1 s. Thus, SL and KAR signaling were involved in soybeanârhizobia interaction and nodulation partly through interactions with hormones, and this may explain the different effects of MXA2 orthologs on legume determinate and indeterminate nodulation. The study provides fresh insights into the roles of GmMAX2âmediated SL/KAR signaling in soybean root hair and nodule formation.