Jasmonic acid: biosynthesis, signal transduction, gene expression

Jasmonic acid (JA) is an ubiquitously occurring plant growth regulator which functions as a signal of developmentally or environmentally regulated expression of Various genes thereby contributing to the defense status of plants [1-5]. The formation of

Diversity in octadecanoid-induced gene expression of tomato

In tomato plants wounding leads to up-regulation of various plant defense genes via jasmonates (Ryan, 1992; Bergey et al., 1996). Using this model system of jasmonic acid (JA) signalling, we analyzed activity of octadecanoids to express JA-responsive g

Coronalon: a powerful tool in plant stress physiology

Coronalon, a synthetic 6-ethyl indanoyl isoleucine conjugate, has been designed as a highly active mimic of octadecanoid phytohormones that are involved in insect and disease resistance. The spectrum of biological activities that is affected by coronal

A Tonic Hyperpolarization Underlying Contrast Adaptation in Cat Visual Cortex

ith a significance level of 5% (SYSTAT, Systat Inc., Evanston, IL ). 34. This project was funded in part by a grant from the Swedish Natural Science Research Council. We thank H. Karlsson, A. T. Proveaux, and D. Powell for assistance with mass spectrometric analysis, J. Lockerman and S. Sharp for oral secretion collection, and M. Brennan for technical assistance. We also thank J. G. Millar, C. A. Ryan, and G. G. Still for helpful comments on the manuscript. 24 January 1997; accepted 17 March 1997 A Tonic Hyperpolarization Underlying Contrast Adaptation in Cat Visual Cortex Matteo Carandini* and David Ferster The firing rate responses of neurons in the primary visual cortex grow with stimulus contrast, the variation in the luminance of an image relative to the mean luminance. These responses, however, are reduced after a cell is exposed for prolonged periods to high-contrast visual stimuli. This phenomenon, known as contrast adaptation, occurs in the cortex and is not present at e