Low Temperature Regulation of Gene Expression in winter Brassica napus.

Bermudagrass (Cynodon dactylon) cultivars may exhibit increased tolerance to cold following periods of exposure to moderately cold temperature (i.e., acclimation). We are evaluating biochemical changes and the regulation of gene expression in two cultivars—'Midiron' and U-3—during this acclimation period. Total membrane lipid fatty acids per unit of total lipids (MLFA/TL; μg·mg–1) increased in crowns over the 4-week exposure to chilling temperatures (8C day/2C night). Of the fatty acids comprising 95% of total MFLA, concentrations of short-chain and saturated FAs declined significantly while unsaturated longer-chain FA concentration increased. As a result, the double bond index (percent of each FA x number of double bonds in the FA) increased during the period of low temperature exposure, indicative of increasing membrane fluidity. Changes in MFLA were evident as early as 4 days following exposure to chilling temperatures. Identification of mRNA species expressed in response to low temperature utilized differential display-PCR. Initial screening with paired T11N1N 2 3'-anchor and 5'-random decamer primers has identified transcripts differentially expressed as early as 23 h post-exposure and was maintained for at least an additional 36 h. Isolation, reamplification, and cloning of these identified PCR products is in progress.

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Linking transcription, RNA polymerase II elongation and alternative splicing

Biochemical Journal ◽

10.1042/bcj20200475 ◽

2020 ◽

Vol 477 (16) ◽

pp. 3091-3104 ◽

Cited By ~ 1

Author(s):

Luciana E. Giono ◽

Alberto R. Kornblihtt

Keyword(s):

Gene Expression ◽

Alternative Splicing ◽

Rna Polymerase Ii ◽

Environmental Changes ◽

Transcription Elongation ◽

Single Gene ◽

Regulation Of Gene Expression ◽

Regulation Of Transcription ◽

Stepping Stones ◽

Eukaryotic Transcription

Gene expression is an intricately regulated process that is at the basis of cell differentiation, the maintenance of cell identity and the cellular responses to environmental changes. Alternative splicing, the process by which multiple functionally distinct transcripts are generated from a single gene, is one of the main mechanisms that contribute to expand the coding capacity of genomes and help explain the level of complexity achieved by higher organisms. Eukaryotic transcription is subject to multiple layers of regulation both intrinsic — such as promoter structure — and dynamic, allowing the cell to respond to internal and external signals. Similarly, alternative splicing choices are affected by all of these aspects, mainly through the regulation of transcription elongation, making it a regulatory knob on a par with the regulation of gene expression levels. This review aims to recapitulate some of the history and stepping-stones that led to the paradigms held today about transcription and splicing regulation, with major focus on transcription elongation and its effect on alternative splicing.

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