Ethylene involvement in the regulation of the H\u3csup\u3e+\u3c/sup\u3e-ATPase \u3ci\u3eCsHA1\u3c/i\u3e gene and of the new isolated ferric reductase \u3ci\u3eCsFRO1\u3c/i\u3e and iron transporter \u3ci\u3eCsIRT1\u3c/i\u3e genes in cucumber plants

In previous works using ethylene inhibitors and precursors, it has been shown that ethylene participates in the regulation of several Fe-deficiency stress responses by Strategy I plants, such as enhanced ferric reductase activity, rhizosphere acidification, and subapical root hair development. Furthermore, recent evidence suggests that ethylene could regulate the expression of both the ferric reductase and the iron transporter genes of Strategy I plants by affecting the FER (or FER-like) transcription factor. Recently, two H+-ATPase genes have been isolated from cucumber roots, CsHA1 and CsHA2. CsHA1 is up-regulated under Fe deficiency while CsHA2 is constitutively expressed. In this work we have cloned and characterized the sequences of the ferric reductase (CsFRO1) and the iron transporter (CsIRT1) genes from cucumber (Cucumis sativus L. cv Ashley). Expression of CsHA1, CsFRO1, and CsIRT1 is diminished in Fe-deficient roots by treatment with ethylene inhibitors, such as Co (cobalt) or AOA (aminooxyacetic acid). Treatment with ethylene precursors, like ACC (1-aminocyclopropane-1-carboxylic acid) or Ethephon (2-chloroethylphosphonic acid), resulted in increased CsHA1, CsFRO1, and CsIRT1 transcript levels and increased ferric reductase activity during early stages of Fe deficiency. These results suggest that ethylene is involved in the regulation of CsHA1, CsFRO1, and CsIRT1 gene expression

Higher-Spin Fermionic Gauge Fields and Their Electromagnetic Coupling

We study the electromagnetic coupling of massless higher-spin fermions in flat space. Under the assumptions of locality and Poincare invariance, we employ the BRST-BV cohomological methods to construct consistent parity-preserving off-shell cubic 1-s-s vertices. Consistency and non-triviality of the deformations not only rule out minimal coupling, but also restrict the possible number of derivatives. Our findings are in complete agreement with, but derived in a manner independent from, the light-cone-formulation results of Metsaev and the string-theory-inspired results of Sagnotti-Taronna. We prove that any gauge-algebra-preserving vertex cannot deform the gauge transformations. We also show that in a local theory, without additional dynamical higher-spin gauge fields, the non-abelian vertices are eliminated by the lack of consistent second-order deformations.Comment: 44 pages; references added, minor changes made, to appear in JHE