Dataset Information

Ice-Binding Proteins in Plants.

ABSTRACT: Sub-zero temperatures put plants at risk of damage associated with the formation of ice crystals in the apoplast. Some freeze-tolerant plants mitigate this risk by expressing ice-binding proteins (IBPs), that adsorb to ice crystals and modify their growth. IBPs are found across several biological kingdoms, with their ice-binding activity and function uniquely suited to the lifestyle they have evolved to protect, be it in fishes, insects or plants. While IBPs from freeze-avoidant species significantly depress the freezing point, plant IBPs typically have a reduced ability to lower the freezing temperature. Nevertheless, they have a superior ability to inhibit the recrystallization of formed ice. This latter activity prevents ice crystals from growing larger at temperatures close to melting. Attempts to engineer frost-hardy plants by the controlled transfer of IBPs from freeze-avoiding fish and insects have been largely unsuccessful. In contrast, the expression of recombinant IBP sequences from freeze-tolerant plants significantly reduced electrolyte leakage and enhanced freezing survival in freeze-sensitive plants. These promising results have spurred additional investigations into plant IBP localization and post-translational modifications, as well as a re-evaluation of IBPs as part of the anti-stress and anti-pathogen axis of freeze-tolerant plants. Here we present an overview of plant freezing stress and adaptation mechanisms and discuss the potential utility of IBPs for the generation of freeze-tolerant crops.

SUBMITTER: Bredow M

PROVIDER: S-EPMC5744647 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Ice-Binding Proteins in Plants.

Bredow Melissa M Walker Virginia K VK

Frontiers in plant science 20171222

Sub-zero temperatures put plants at risk of damage associated with the formation of ice crystals in the apoplast. Some freeze-tolerant plants mitigate this risk by expressing ice-binding proteins (IBPs), that adsorb to ice crystals and modify their growth. IBPs are found across several biological kingdoms, with their ice-binding activity and function uniquely suited to the lifestyle they have evolved to protect, be it in fishes, insects or plants. While IBPs from freeze-avoidant species signific ...[more]

PMID: 29312400

Similar Datasets

Project description:Ice-binding proteins (IBPs) have been identified in numerous polar algae and bacteria, but so far not in any cyanobacteria, despite the abundance of cyanobacteria in polar regions. We previously reported strong IBP activity associated with an Antarctic Nostoc species. In this study, to identify the proteins responsible, as well as elucidate their origin, we sequenced the DNA of an environmental sample of this species, designated Nostoc sp. HG1, and its bacterial community and attempted to identify IBPs by looking for known IBPs in the metagenome and by looking for novel IBPs by tandem mass spectrometry (MS/MS) proteomics analyses of ice affinity-purified proteins. The metagenome contained over 116 DUF3494-type IBP genes, the most common type of IBP identified so far. One of the IBPs could be confidently assigned to Nostoc, while the others could be attributed to diverse bacteria, which, surprisingly, accounted for the great majority of the metagenome. Recombinant Nostoc IBPs (nIBPs) had strong ice-structuring activities, and their circular dichroism spectra were consistent with the secondary structure of a DUF3494-type IBP. nIBP is unusual in that it is the only IBP identified so far to have a PEP (amino acid motif) C-terminal signal, a signal that has been associated with anchoring to the outer cell membrane. These results suggest that the observed IBP activity of Nostoc sp. HG1 was due to a combination of endogenous and exogenous IBPs. Amino acid and nucleotide sequence analyses of nIBP raise the possibility that it was acquired from a planctomycete.IMPORTANCE The horizontal transfer of genes encoding ice-binding proteins (IBPs), proteins that confer freeze-thaw tolerance, has allowed many microorganisms to expand their ranges into polar regions. One group of microorganisms for which nothing is known about its IBPs is cyanobacteria. In this study, we identified a cyanobacterial IBP and showed that it was likely acquired from another bacterium, probably a planctomycete. We also showed that a consortium of IBP-producing bacteria living with the Nostoc contribute to its IBP activity.

Dataset Information

Ice-Binding Proteins in Plants.

Publications

Ice-Binding Proteins in Plants.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets