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Title: Effects of freezing and cold acclimation on the plasma membrane of isolated protoplasts, progress report

Our goal is to provide a mechanistic understanding of the cellular and molecular aspects of freezing injury and cold acclimation from a perspective of the structural and functional integrity of the plasma membrane -- the primary site of freezing injury in winter cereals. We have utilized protoplasts isolated from leaves of winter rye (Secale cereale L. cv Puma) to study the cryobehavior of the plasma membrane during a freeze/thaw cycle. The focus of our current studies is on lesions in the plasma membrane that result from severe freeze-induced dehydration and result in the alteration of the semipermeable characteristics of the plasma membrane so that the protoplasts are osmotically unresponsive. In protoplasts isolated from non-acclimated rye leaves (NA protoplasts), injury is associated with the formation of aparticulate domains in the plasma membrane, aparticulate lamellae subtending the plasma membrane, and lamellar-to-hexagonal II phase transitions in the plasma membrane and the subtending lamellae. However, lamellar-to-hexagonal II phase transitions are not observed following severe dehydration of protoplasts isolated from cold-acclimated rye leaves (ACC protoplasts). Rather, injury is associated with the fracture-jump lesion,'' which, in freeze-fracture electron microscopy studies, is manifested as localized deviations in the fracture face of the plasma membrane. The fracture planemore » jumps'' from the plasma membrane to either subtending aparticulate lamellae or aparticulate regions of various endomembranes (predominantly chloroplast envelopes) that are in close apposition with the plasma membrane.« less
Authors:
Publication Date:
OSTI Identifier:
6551768
Report Number(s):
DOE/ER/13214-10
ON: DE93013329
DOE Contract Number:
FG02-84ER13214
Resource Type:
Technical Report
Research Org:
Cornell Univ., Ithaca, NY (United States). Dept. of Soil, Crop and Atmospheric Sciences
Sponsoring Org:
DOE; USDOE, Washington, DC (United States)
Country of Publication:
United States
Language:
English
Subject:
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; 09 BIOMASS FUELS; CELL MEMBRANES; FREEZING; OATS; BIOLOGICAL ADAPTATION; PLANT CELLS; RYE; CRYOBIOLOGY; PROGRESS REPORT; ULTRASTRUCTURAL CHANGES; BIOLOGY; CELL CONSTITUENTS; CEREALS; DOCUMENT TYPES; GRAMINEAE; LILIOPSIDA; MAGNOLIOPHYTA; MEMBRANES; MORPHOLOGICAL CHANGES; PLANTS 560400* -- Other Environmental Pollutant Effects; 090800 -- Biomass Fuels-- Production-- (1990-)