© 2003 Heron Publishing—Victoria, Canada
Novel plasmodesmata association of dehydrin-like proteins in cold- acclimated red-osier dogwood (Cornus sericea)
Dale T. Karlson (1, 2), Takeshi Fujino (3, 4), Satoshi Kimura (5), Kei'ichi Baba (3), Takao Itoh (3) and Edward N. Ashworth (1, 6)
1. Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907-1165, USA / 2. Department of Low Temperature Sciences, National Agricultural Research Center for Hokkaido Region, Hitsujigaoka, Sapporo 062-8555,
Japan / 3. Wood Research Institute, Kyoto University, Uji, Kyoto, Japan / 4. Forest Biotechnology Group, Department of Forestry, North Carolina State University, Raleigh, NC 27695, USA / 5. Forestry and Forest Products Research Institute, Tsukuba, Ibaraki 305-8687, Japan / 6. Author to whom correspondence is addressed (ashworth@purdue.edu) / Received November 6, 2002; accepted January 24, 2003; published online July 1, 2003
Summary
Dehydrins are proteins associated with conditions affecting the water status of plant cells, such as drought, salinity, freezing
and seed maturation. Although the function of dehydrins remains unknown, it is hypothesized that they stabilize membranes
and macromolecules during cellular dehydration. Red-osier dogwood (Cornus sericea L.), an extremely freeze-tolerant woody plant, accumulates dehydrin-like proteins during cold acclimation and the presence
of these proteins is correlated with increased freeze tolerance (Karlson 2001, Sarnighausen et al. 2002, Karlson et al. 2003).
Our objective was to determine the location of dehydrins in cold-acclimated C. sericea stems in an effort to provide insight into their potential role in the freeze tolerance of this extremely cold hardy species.
Abundant labeling was observed in the nucleus and cytoplasm of cold-acclimated C. sericea stem cells. In addition, labeling was observed in association with plasmodesmata of cold-acclimated vascular cambium cells.
The unique association of dehydrin-like proteins with plasmodesmata has not been reported previously.
Keywords:
dehydrins, desiccation stress, freeze tolerance, immunolocalization.
