title: Molecular foundations of chilling-tolerance of modern maize.
abstract: BACKGROUND
  Recent progress in selective breeding of maize (Zea mays L.) towards adaptation to temperate climate has allowed the production of inbred lines withstanding cold springs with temperatures below 8 °C or even close to 0 °C, indicating that despite its tropical origins maize is not inherently cold-sensitive.
  
  
  RESULTS
  Here we studied the acclimatory response of three maize inbred lines of contrasting cold-sensitivity selected basing on multi-year routine field data. The field observations were confirmed in the growth chamber. Under controlled conditions the damage to the photosynthetic apparatus due to severe cold treatment was the least in the cold-tolerant line provided that it had been subjected to prior moderate chilling, i.e., acclimation. The cold-sensitive lines performed equally poorly with or without acclimation. To uncover the molecular basis of the attained cold-acclimatability we performed comparative transcriptome profiling of the response of the lines to the cold during acclimation phase by means of microarrays with a statistical and bioinformatic data analysis.
  
  
  CONCLUSIONS
  The analyses indicated three mechanisms likely responsible for the cold-tolerance: acclimation-dependent modification of the photosynthetic apparatus, cell wall properties, and developmental processes. Those conclusions supported the observed acclimation of photosynthesis to severe cold at moderate chilling and were further confirmed by experimentally showing specific modification of cell wall properties and repression of selected miRNA species, general regulators of development, in the cold-tolerant line subjected to cold stress.
authors.affiliation: Department of Plant Molecular Ecophysiology, Institute of Plant Experimental Biology and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Alicja
authors.initials: A
authors.lastname: Sobkowiak
authors.affiliation: Department of Plant Molecular Ecophysiology, Institute of Plant Experimental Biology and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Jończyk
authors.affiliation: Plant Breeding Smolice Co. Ltd., Smolice 146, 63-740, Kobylin, Poland.
authors.forename: Józef
authors.initials: J
authors.lastname: Adamczyk
authors.affiliation: Department of Plant Molecular Ecophysiology, Institute of Plant Experimental Biology and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Jarosław
authors.initials: J
authors.lastname: Szczepanik
authors.affiliation: Department of Plant Molecular Ecophysiology, Institute of Plant Experimental Biology and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Danuta
authors.initials: D
authors.lastname: Solecka
authors.affiliation: Department of Molecular Biology, Institute of Biochemistry, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Kuciara
authors.affiliation: Department of Molecular Biology, Institute of Biochemistry, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.|Present address: Department of Genetics, Institute of Psychiatry and Neurology in Warsaw, Sobieskiego 9, 02-957, Warsaw, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Hetmańczyk
authors.affiliation: Department of Molecular Biology, Institute of Biochemistry, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Trzcinska-Danielewicz
authors.affiliation: Department of Plant Molecular Ecophysiology, Institute of Plant Experimental Biology and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Grzybowski
authors.affiliation: Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106, Warszawa, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Skoneczny
authors.affiliation: Department of Molecular Biology, Institute of Biochemistry, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland.
authors.forename: Jan
authors.initials: J
authors.lastname: Fronk
authors.affiliation: Department of Plant Molecular Ecophysiology, Institute of Plant Experimental Biology and Biotechnology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warszawa, Poland. pawes@biol.uw.edu.pl.
authors.forename: Paweł
authors.initials: P
authors.lastname: Sowiński
mesh_terms: D000064:Acclimatization; D003080:Cold Temperature; D018744:DNA, Plant / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D063990:Gene Ontology; D017343:Genes, Plant; D020411:Oligonucleotide Array Sequence Analysis; D010788:Photosynthesis; D000069600:Plant Breeding; D011401:Promoter Regions, Genetic; D059467:Transcriptome; D003313:Zea mays / Q000235:genetics / Q000502:physiology*
chemical_list: D018744:DNA, Plant