Spatial and temporal dynamics of jasmonate synthesis and accumulation in Arabidopsis in response to wounding.

A new metabolite profiling approach combined with an ultrarapid sample preparation procedure was used to study the temporal and spatial dynamics of the wound-induced accumulation of jasmonic acid (JA) and its oxygenated derivatives in Arabidopsis thaliana. In addition to well known jasmonates, including hydroxyjasmonates (HOJAs), jasmonoyl-isoleucine (JA-Ile), and its 12-hydroxy derivative (12-HOJA-Ile), a new wound-induced dicarboxyjasmonate, 12-carboxyjasmonoyl-l-isoleucine (12-HOOCJA-Ile) was discovered. HOJAs and 12-HOOCJA-Ile were enriched in the midveins of wounded leaves, strongly differentiating them from the other jasmonate metabolites studied. The polarity of these oxylipins at physiological pH correlated with their appearance in midveins. When the time points of accumulation of different jasmonates were determined, JA levels were found to increase within 2-5 min of wounding. Remarkably, these changes occurred throughout the plant and were not restricted to wounded leaves. The speed of the stimulus leading to JA accumulation in leaves distal to a wound is at least 3 cm/min. The data give new insights into the spatial and temporal accumulation of jasmonates and have implications in the understanding of long-distance wound signaling in plants.

Developing Eyecare Partnerships

Improving the Commisioning and Provision of Eyecare Services in Northern Ireland.

Natural Arabidopsis brx loss-of-function alleles confer root adaptation to acidic soil.

Soil acidification is a major agricultural problem that negatively affects crop yield. Root systems counteract detrimental passive proton influx from acidic soil through increased proton pumping into the apoplast, which is presumably also required for cell elongation and stimulated by auxin. Here, we found an unexpected impact of extracellular pH on auxin activity and cell proliferation rate in the root meristem of two Arabidopsis mutants with impaired auxin perception, axr3 and brx. Surprisingly, neutral to slightly alkaline media rescued their severely reduced root (meristem) growth by stimulating auxin signaling, independent of auxin uptake. The finding that proton pumps are hyperactive in brx roots could explain this phenomenon and is consistent with more robust growth and increased fitness of brx mutants on overly acidic media or soil. Interestingly, the original brx allele was isolated from a natural stock center accession collected from acidic soil. Our discovery of a novel brx allele in accessions recently collected from another acidic sampling site demonstrates the existence of independently maintained brx loss-of-function alleles in nature and supports the notion that they are advantageous in acidic soil pH conditions, a finding that might be exploited for crop breeding.

Developing a Workplace Policy on Domestic Violence and Abuse (PDF 219KB)

This guide for employers has been produced by the Regional Steering Group on Domestic Violence in line with the strategy and action plan “Tackling Violence at Home” published in October 2005. The Regional Steering Group is a group of about 30 members representing the statutory and voluntary agencies involved in dealing with domestic violence. The guidance provides advice on how employers can develop increased awareness and more effective responses to domestic violence in the workplace for the benefit of all staff. The Regional Steering Group acknowledges that some employers already have good workplace policies in place and it encourages all employers across the public, private, voluntary and community sectors to use the guidance to develop a workplace policy on domestic violence. åÊ

Developing Better Services Modernising Hospitals and Reforming Structures

Developing Better Services Modernising Hospitals and Reforming Structures

Developing a Regional Strategy for the Health and Personal Social Services - Appendix 1 (PDF 35KB)

Summary of Relevant Policy Reviews

Developing a Regional Strategy for the Health and Personal Social Services - Appendix 2 (PDF 20KB)

Consultation Reply Form

Developing a Regional Strategy for the Health and Personal Social Services (PDF 73KB)

2002 - 2022