DEHYDRINS - GENES, PROTEINS, AND ASSOCIATIONS WITH PHENOTYPIC TRAITS

Dehydrin proteins (late embryogenesis abundant (LEA) D11 family) are p roduced in a wide variety of plant species in response to environmenta l stimuli with a dehydrative component, including drought, low tempera ture, salinity, and developmental stages such as seed and pollen matur ation. Despite their widespread occurrence and abundance in cells unde r dehydrative conditions, the biochemical role of dehydrins remains el usive. The subcellular location of dehydrins is consistent with a bioc hemical role as an intracellular stabilizer, possibly with surfactant characteristics, acting upon targets in both the nucleus and cytoplasm . In some species, dehydrin loci are located within quantitative trait loci (QTL) intervals for important phenotypic traits including winter hardiness in barley (Hordeum vulgare L.) and anthesis-silking interva l in maize (Zea mays L.). Dehydrin loci tend to be multigenic and occu r in clusters on more than one chromosome. Investigations are currentl y under way in our laboratory and others' to move beyond protein accum ulation studies and correlations with QTL to uncover direct cause-and- effect relationships between dehydrin (dhn) genes and phenotypes assoc iated with physiological responses to stress.