Characterisation of rapid alkalinisation factors in Physcomitrium patens reveals functional conservation in tip growth

Summary Small signalling peptides are key molecules for cell‐to‐cell communications in plants. The cysteine‐rich signalling peptide, rapid alkalinisation factors (RALFs) family are involved in diverse developmental and stress responses and have expanded considerably during land plant evolution, impl...

Full description

Saved in:
Bibliographic Details
Published in:The New phytologist 2022-03, Vol.233 (6), p.2442-2457
Main Authors: Ginanjar, Eggie Febrianto, Teh, Ooi‐kock, Fujita, Tomomichi
Format: Article
Language:English
Subjects:
Aquatic plants
Arabidopsis - genetics
Arabidopsis - metabolism
bryophytes
Bryopsida - metabolism
Divergence
Elongation
Fluorescence
Functionals
Growth
Homology
Land acquisition
Morphogenesis
Peptides
Physcomitrium
Physcomitrium patens
Plant Proteins - genetics
Plant Proteins - metabolism
Plants - metabolism
Proteolysis
rapid alkalinisation factors (RALFs)
reverse genetics
Signaling
signalling peptides
tip growth
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Summary Small signalling peptides are key molecules for cell‐to‐cell communications in plants. The cysteine‐rich signalling peptide, rapid alkalinisation factors (RALFs) family are involved in diverse developmental and stress responses and have expanded considerably during land plant evolution, implying neofunctionalisations in the RALF family. However, the ancestral roles of RALFs when land plant first acquired them remain unknown. Here, we functionally characterised two of the three RALFs in bryophyte Physcomitrium patens using loss‐of‐function mutants, overexpressors, as well as fluorescent proteins tagged reporter lines. We showed that PpRALF1 and PpRALF2 have overlapping functions in promoting protonema tip growth and elongation, showing a homologous function as the Arabidopsis RALF1 in promoting root hair tip growth. Although both PpRALFs are secreted to the plasma membrane on which PpRALF1 symmetrically localised, PpRALF2 showed a polarised localisation at the growing tip. Notably, proteolytic cleavage of PpRALF1 is necessary for its function. Our data reveal a possible evolutionary origin of the RALF functions and suggest that functional divergence of RALFs is essential to drive complex morphogenesis and to facilitate other novel processes in land plants.
ISSN:0028-646X
1469-8137
DOI:10.1111/nph.17942