Dormancy and DOG1

We found that alternative polyadenylation results in production of two DOG1 transcripts: a shorter two exonic short DOG1 (shDOG1) and longer three exonic long DOG1 (lgDOG1). Our work showed that the shDOG1 transcript is evolutionary conserved at the level of amino acids, translated and sufficient to complement dog1 mutant.

Further reading:
Cyrek and Fedak Plant Phys 2016 click for PDF

DOG1 alternative splicing

DOG1 alternative splicing. Second intron of DOG1 is subject to alternative splicing, generating four different isoforms. By studying the regulation of this alternative splicing we described a tight coupling between transcription and alternative splice site selection. We showed that mutations in transcription elongation factor TFIIS lead to selection of proximal splice sites not only on DOG1 but also at majority of tested genome wide targets - suggesting existence of a kinetic coupling between PolII elongation and splicing in plants. We have also shown that  alternative splice sites are active players in PolII elongation control. We hypothesized that alternative splicing may locally pause the elongating PolII using a chromatin based mechanism that is centered around the spliceosomal disassembly factor NTR1.  
We have also helped to describe a mechanism where alternative splicing control by light is mediated by changes in Pol II speed that is dependent on the TFIIS elongation factor.

Further reading     
Dolata and Guo, EMBO J 2015  click for PDF     
Brzyzek Transcription 2015  click for PDF 
Godoy Herz Mol Cell 2019 click for PDF 

DOG1 antisense regulation

Transcription generates an extensive array of non-protein-coding RNA (ncRNA), the functional significance of which is mostly unknown. Studies in yeast, humans, drosophila, bacteria and plants have shown that the majority of nucleotides in these genomes are transcribed, generating a mixture of long and short RNAs, most of which are non-coding. This non-coding transcription changes in a complex manner during development and in response to environmental signals. One specific class of ncRNA are antisense transcripts.
 We have recently characterized an antisense transcript originating close to DOG1 proximal (main) termination site that strongly inhibits dormancy strength and DOG1 expression.  We further showed that this transcript acts in cis as it is unable to silence DOG1 transcribed from a second allele.
We also showed that in mature plants DOG1 antisense acts as a sensor for a plant hormone ABA allowing the mature plant to upregulate DOG1 expression in response to drought. This allowed us to characterise DOG1 function outside seed in conferring increased drought tolerance.

Further reading
Fedak and Palusinska, PNAS 2016 click for PDF
Yatusevich, EMBO Rep. click for PDF


For list of all papers from the lab please click here