Cold induced changes in the water balance affect immunocytolocalization pattern of one of the aquaporins in the vascular system in the leaves of maize (Zea mays L.).
Chilling stress is known to affect the water balance in plants, which often manifests itself in the decrease of the water potential in different organs. Relationships between chilling, assimilate transport and water balance are far from being understood. Although aquaporins play a key role in regulating water balance in plants, especially under stress conditions, the role of individual aquaporins in stress response remains unclear. In this report we show the specific localization within plasma membranes of one of the aquaporins (PIP2;3) in the leaves of two maize inbred lines differing in their chilling-sensitivity. This form of aquaporin has been also observed in thick-walled sieve elements - an additional type of sieve tubes of unclear function found only in monocotyledons. Moderate chilling (about 15°C) caused significant reduction of labelling in these cells accompanied by a steep decrease in the water potential in leaves of chilling-sensitive maize line. Our results suggest that both PIP2;3 and thick-walled sieve tubes may be an unknown element of the mechanism of the response of maize to cold stress.
Plant Breeding and Acclimatization Institute - National Research Institute, Department of Plant Biochemistry and Physiology, Radzików, 05-870 Błonie, Poland. Electronic address: a.bilska@ihar.edu.pl.
Anna
A
Bilska-Kos
Department of Plant Molecular Ecophysiology, Faculty of Biology, Institute of Plant Experimental Biology and Biotechnology, University of Warsaw, 02-096 Warsaw, Miecznikowa 1, Poland.
Jarosław
J
Szczepanik
Department of Plant Molecular Ecophysiology, Faculty of Biology, Institute of Plant Experimental Biology and Biotechnology, University of Warsaw, 02-096 Warsaw, Miecznikowa 1, Poland.
Paweł
P
Sowiński
D020346:Aquaporins / Q000235:genetics / Q000378:metabolism*; D003080:Cold Temperature; D018506:Gene Expression Regulation, Plant; D018515:Plant Leaves / Q000502:physiology / Q000648:ultrastructure; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D058526:Plant Vascular Bundle / Q000502:physiology / Q000648:ultrastructure; D021381:Protein Transport; D013312:Stress, Physiological; D014867:Water / Q000378:metabolism*; D003313:Zea mays / Q000502:physiology* / Q000648:ultrastructure
D020346:Aquaporins; D010940:Plant Proteins; D014867:Water
Aquaporins; Chilling stress; Immunogold; Thick-walled sieve tubes; Water potential; Zea mays