Mutually opposing activity of PIN7 splicing isoforms is required for auxin-mediated tropic responses in Arabidopsis thaliana

0552833 - ÚEB 2022 RIV GB eng J - Journal Article
Kashkan, Ivan - Hrtyan, M. - Retzer, Katarzyna - Humpolíčková, Jana - Jayasree, A. - Filepová, Roberta - Vondráková, Zuzana - Simon, Sibu - Rombaut, D. - Jacobs, T. B. - Frilander, M. J. - Hejátko, J. - Friml, J. - Petrášek, Jan - Růžička, Kamil
Mutually opposing activity of PIN7 splicing isoforms is required for auxin-mediated tropic responses in Arabidopsis thaliana.
New Phytologist. Roč. 233, č. 1 (2022), s. 329-343. ISSN 0028-646X. E-ISSN 1469-8137
R&D Projects: GA ČR(CZ) GA19-23773S; GA ČR(CZ) GA19-18917S; GA MŠMT(CZ) EF16_019/0000738; GA MŠMT(CZ) LM2018129; GA MŠMT(CZ) EF16_013/0001775
Institutional support: RVO:61389030 ; RVO:61388963
Keywords : alternative splicing * Arabidopsis thaliana * auxin * auxin transport * frap * PINs * plant development * RNA processing
OECD category: Developmental biology; Plant sciences, botany (UOCHB-X)
Impact factor: 9.4, year: 2022
Method of publishing: Open access
http://doi.org/10.1111/nph.17792

Advanced transcriptome sequencing has revealed that the majority of eukaryotic genes undergo alternative splicing (AS). Nonetheless, little effort has been dedicated to investigating the functional relevance of particular splicing events, even those in the key developmental and hormonal regulators. Combining approaches of genetics, biochemistry and advanced confocal microscopy, we describe the impact of alternative splicing on the PIN7 gene in the model plant Arabidopsis thaliana. PIN7 encodes a polarly localized transporter for the phytohormone auxin and produces two evolutionarily conserved transcripts, PIN7a and PIN7b. PIN7a and PIN7b, differing in a four amino acid stretch, exhibit almost identical expression patterns and subcellular localization. We reveal that they are closely associated and mutually influence each other's mobility within the plasma membrane. Phenotypic complementation tests indicate that the functional contribution of PIN7b per se is minor, but it markedly reduces the prominent PIN7a activity, which is required for correct seedling apical hook formation and auxin-mediated tropic responses. Our results establish alternative splicing of the PIN family as a conserved, functionally relevant mechanism, revealing an additional regulatory level of auxin-mediated plant development.
Permanent Link: http://hdl.handle.net/11104/0327927